The present invention relates generally to the field of microbiological analysis. More particularly, it relates to a microbiological control device for controlling a fluid to be analyzed, this liquid being capable of containing at least one microorganism. It also provides a provisioning process for such a device and uses of such a device in a control method for a liquid to be analyzed may contain at least one microorganism.

The invention is more particularly the field of industrial microbiological control food, pharmaceutical or cosmetic.

The invention was developed following work has benefited from the National Center for Space Studies participation (CNES).

There are many situations in which one seeks to control the presence of at least one microorganism in a liquid, usually to be able to note the absence of this microorganism.

Of course, the liquid to be analyzed may be a biological fluid (whole blood, serum, plasma, urine, cerebrospinal fluid, organic secretion, etc ....) - However, the liquid can also be an industrial liquid, especially a food liquid (water, generally including drink fruit juice, milk, soda, etc ..) or a liquid pharmaceutical or cosmetic.

Numerous laboratory techniques are known that allow you to filter the liquid to be analyzed to collect possible microorganisms contained in the liquid, to culture these microorganisms to then be able to detect them, count them, characterize and / or identify them. These techniques require a number of well-known laboratory manipulations.

In these techniques, it is sometimes necessary to use a filter device which comprises a closed internal space bounded by an enclosure and which is intended to receive the liquid to be analyzed. Such a technique is

notably called "membrane filtration". A microbiological filtration means, for example a membrane filter is arranged in the closed inner space and separated, in the closed internal space, a first compartment from a second compartment from the closed internal space. The device comprises an inlet port for the liquid to be analyzed which opens into the first compartment from the closed internal space.

In known filtration devices, such as those of EP-1783494, there is provided a suction port which is intended to be connected to an external suction source. In the use of such a device, so one must connect the external suction source to the suction port for generating, upon the introduction of the liquid to be analyzed into the device through the inlet port, a vacuum inside the closed internal space, this depression being favorable, if necessary, filtration.

Once the carried filtration, the microorganisms being retained on the filtration means, the device is opened to recover the filtration means, which is transferred into a culturing device to allow incubation of microorganisms.

One such technique is easily attainable in the lab.

However, such a technique is difficult to implement in an operational environment, especially in an industrial environment in which liquids are produced, packaged, distributed or used. Indeed, in this context, it is advantageous to have means for detecting possible contamination of the liquid by a microorganism undesirable. However, conventional techniques as described above require to transport a sample of the liquid to be analyzed at a laboratory where the usual methods can be implemented. It is indeed not very possible to achieve these usual situ operations on the industrial site of production, packaging, distribution or use of the liquid. Indeed the handling of a contaminated liquid in such an environment would pose the risk of propagation in the event of contamination of mishandling. Furthermore, the culturing step possible microorganisms require the presence of a nutrient medium which is, by definition, conducive to the development of microorganisms. It is of course not wish such a nutrient medium is introduced into such an industrial context. In addition, sensing the usual techniques also need to protect the sample for analysis from any external contamination, thus working in a sterile environment as possible to avoid false positives. culturing step possible microorganisms require the presence of a nutrient medium which is, by definition, conducive to the development of microorganisms. It is of course not wish such a nutrient medium is introduced into such an industrial context. In addition, sensing the usual techniques also need to protect the sample for analysis from any external contamination, thus working in a sterile environment as possible to avoid false positives. culturing step possible microorganisms require the presence of a nutrient medium which is, by definition, conducive to the development of microorganisms. It is of course not wish such a nutrient medium is introduced into such an industrial context. In addition, sensing the usual techniques also need to protect the sample for analysis from any external contamination, thus working in a sterile environment as possible to avoid false positives.

The invention therefore aims to provide a device and a microbiological method for controlling a liquid to be analyzed that allow particularly simplified control operations, it would even be possible to use or driving outside the microbiological laboratory including in an industrial environment.

To this end, the invention firstly proposes a microbiological control device for controlling a fluid to be analyzed may contain at least one microorganism of the type comprising:

- a closed internal space defined by an enclosure for receiving the liquid to be analyzed;

- a microbiological filter means arranged in the closed inner space and separating in the closed internal space, a first compartment from a second compartment from the closed internal space;

- an inlet port for the liquid to be analyzed, the input port opening into the first compartment from the closed internal space.

Such a device is characterized in that, in a configuration providing microbiological control device before use, microbiological control device comprises, inside the closed internal space, a nutritive layer comprising a composition of a microbiological culture medium, the nutritive layer being in contact with the filtration means, in that the input port of the microbiological monitoring device comprises a shutter, and in that, in the configuration of provision of the device microbiological control before use:

- the closure of the input port is in a closed state to close the inlet port and the closed inner space so airtight;

- the absolute gas pressure within the enclosed internal space, reduced to a temperature of 25 ° C is strictly less than the standard atmospheric pressure LBAR at 25 ° C, so that the device is adapted to create a suction through the input port during a first opening of the shutter.

According to other optional features of a device according to the invention, taken alone or in combination:

- In the configuration of providing microbiological control device prior to use, the closed inner space is isolated from any external suction source.

- The second compartment of the closed inner space is free from fluid communication with port outside the closed internal space.

- In the configuration of provision of the device before use, the microbiological culture medium of the nutritive layer is dehydrated.

- Any fluid exchange between the first and the second compartment from the closed inner space is through the filtration means.

- Microbiological control device comprises a support for the filtering means and the nutritive layer.

- The support for the filtering means comprises a grid, for example in the form of a perforated plate extending across the closed inner space between the first compartment and the second compartment.

- The nutritive layer is arranged between the filtration means and the support for the filtering means.

- The nutritive layer is locally clamped between the filtering means and the support for the filtering means.

- The support for the filtering means comprises supporting walls arranged in the second compartment.

- The support walls are perforated to permit the flow of fluid on both sides of said baffles in the second compartment. - A water-absorbent material is arranged in the second compartment.

- The closure of the inlet port has a valve.

- The closure of the input port has a waterproof membrane, and the shutter of the inlet port is brought into an open state by breaking the membrane.

- The enclosure of microbiological control device comprises at least a main body defining at least in part the second compartment, and has a lid which delimits at least partly the first compartment, the main body and the cover are formed of separate parts joined to each other to form the microbiological control device.

- The enclosure of microbiological control device comprises at least one transparent portion.

- The inlet port has a tundish with several separate passages for the liquid to be analyzed.

- The input port includes an inner portion which opens into the first compartment from the closed internal space, and an external connecting portion to a container of liquid to be analyzed, and the shutter of the inlet port is interposed between the inner portion and the outer portion of the inlet port.

- In the provision of configuration of microbiological control device prior to use, an absolute gas pressure within the enclosed internal space is such that it allows the input of a predetermined volume of test sample without fluid discharge from the internal space at the input of a predetermined volume of the sample to be analyzed. In particular, the absolute gas pressure within the enclosed internal space is preferably strictly less than the standard atmospheric pressure multiplied by the ratio of the final free volume in the inner space after the input of a predetermined volume of the test sample divided by the volume of the internal space. In practice,

The invention also relates to a provisioning method for microbiological control device for controlling a fluid to be analyzed may contain at least one microorganism of the type comprising providing a microbiological control device comprising:

- an enclosure intended to define a closed inner space for receiving the liquid to be analyzed;

- a microbiological filter means intended to be arranged in the closed inner space and to separate in the closed internal space, a first compartment from a second compartment from the closed internal space;

- an inlet port for the liquid to be analyzed, the input port opening into the first compartment from the closed internal space,

characterized in that the method comprises providing a nutritive layer, adapted to be received within the closed inner space and impregnated with a composition of a microbiological culture medium, the nutritive layer being in contact with the filtering means,

and in that the method comprises, before connecting the microbiological control device to a liquid container to be analyzed, successively and in this order:

- a depressurization step for lowering the absolute gas pressure within the enclosed internal space;

- a closing step to close the internal space closed in a sealed manner to the air.

The invention also relates to the use of a microbiological monitoring device having any of the characteristics listed above, in a control method of a liquid to be analyzed may contain at least one microorganism.

This use may further comprise the steps of:

- connecting a liquid container to be analyzed to the input port;

- opening the shutter from the input port to allow passage of the liquid to be analyzed from the container to the closed inner space.

It may include the further steps of:

- close the shutter of the input port;

- disconnect the liquid container to be analyzed;

- incubating in the microbiological control device, any microorganism initially contained in the liquid to be analyzed.

It can include a step of detecting even later, count, identify and / or visually characterize a potential microorganism initially contained in the liquid to be analyzed by viewing through a transparent portion of the enclosure of microbiological control device.

Various other characteristics appear from the description given below with reference to the accompanying drawings which, as non-limiting examples, embodiments of the object of the invention.

Figure 1 is an exploded perspective view of a first embodiment of a device according to the invention.

Figure 2 is a perspective view of the device of Fig. 1, assembled.

Figure 3 is a sectional view of the device of Fig. 2, the sectional plane being shown in Fig. 1.

Figure 4 is a perspective view, seen from below, of the device of Fig cover. 1.

Illustrated in Figures 1-4 an embodiment of a microbiological control device 10 for controlling a fluid to be analyzed, said liquid being capable of containing at least one microorganism.

Figure 5 is an exploded perspective view of a second embodiment of a device according to the invention.

Figure 6 is a perspective view, from below, of the main body and the attached base of the second exemplary embodiment of a device according to the invention.

Figure 7 is a sectional view of the device of Fig. 5, the sectional plane being shown in Fig. 5.

For the purposes of the present invention, the term microorganism covers including gram-positive bacteria and gram-negative yeasts, amoebas, viruses and generally unicellular organisms, invisible to the naked eye, which can be handled and multiplied in the laboratory.

According to a preferred embodiment of the invention, the microorganism is a bacterium, gram negative or positive, or yeast.

This microbiological control device, a first embodiment is illustrated in FIGS. 1-4 and a second embodiment is illustrated in FIGS. 5 to 7 in its operational state illustrated in FIGS. 2 and 3 for the first example embodiment, and Fig. 7 for the second example embodiment has a closed inner space 12, delimited by a chamber for receiving the liquid to be analyzed. The two embodiments shown will be mainly described together. The features that distinguish one from the other will be referred to as and.

In the examples shown, the enclosure of microbiological control device comprises at least one main body 14 and a lid 16. The main body 14 and cover 16 are formed of separate parts which are assembled to each other to form the enclosure of microbiological control device. The cover 16 comes close the main body 14 to define the closed inner space 12 of microbiological control device 10. The cover 16 therefore has a shape complementary to that of the main body 14 to ensure closing of the latter.

In the examples illustrated, the main body 14 present a bottom wall 18 and a peripheral side wall 20 so that the main body 14 is opened by an end opposite its bottom wall 18. In the example shown, the side wall device 20 has a central axis Al. the bottom wall 18 is in the illustrated case a transverse wall perpendicular to the central axis Al of the main body 14. in the first embodiment, the bottom wall 18 is made in one piece with the peripheral side wall 20, while in the second embodiment, the bottom wall 18 is formed as a separate piece that comes close, down, closed inner space 12. in the case where the bottom wall 18 is formed as a separate piece,it can be assembled to the peripheral side wall 20 by any known means, for example by simple press-fitting, gluing, welding, screwing by mechanical fastening clips, etc., and may then provide a seal , to ensure that, when the bottom wall 18 is joined to the peripheral side wall 20, it sealingly closes the internal space 12 closed.

For clarity of the description, it is assumed in the following description that the central axis Al is vertically oriented and the bottom wall 18 is arranged at a lower end of microbiological control device, the peripheral side wall 20 s' extending upwardly, in the direction of the axis Al, since the bottom wall 18. However, the verticality of notions of horizontality, and the terms "top", "bottom", "upper" and "lower" are used only with reference to the orientation of microbiological control device as illustrated in the figures, so relative to each other, without having any limiting character on the scope of the invention or on the orientation of the control device microbiological use.

The peripheral side wall 20 is for example a surface of revolution about the central axis Al. In the example shown, lateral wall 20 is substantially cylindrical. However, other forms may be proposed.

Accordingly, the lid 16 has a transverse wall 22, perpendicular to the central axis A, which in this case has a substantially circular shape corresponding to the geometry of an upper edge 24 of the peripheral side wall 20 of the main body 14 . in the example illustrated, the cover 16 has a cylindrical collar 26, in

the occurrence circularly cylindrical about the central axis A which extends downwardly from an underside of the transverse wall 22 of the cover. The cylindrical collar 26 is intended to engage in the vertical direction of the central axis A, inside an upper end of the peripheral side wall 20 of the main body 14.

It is noted that, in the first exemplary embodiment, the upper end of the peripheral side wall 20 of the main body presents, on an internal face, a transverse recess which defines an annular bearing surface 28 of central axis Al Tour to the top. The cylindrical collar 26 has a lower edge 30 which, when the cover 16 is assembled on the main body 14, comes opposite the annular support surface 28.

Microbiological control device 10 according to the invention comprises a microbiological filter means 32 which is arranged in the closed inner space 12 and which separates in the closed internal space, a first compartment 12a and a second 12b compartment space internal 12 closed.

In the illustrated example, the first compartment 12a is defined at least in part by the cover 16, while the second compartment 12b is defined at least in part by the main body 14.

Indeed, the microbiological filter means 32 extends in the closed internal space 12 substantially transversely, according to the whole section of the closed inner space. In the example, the filtration means microbiological 32 has a substantially planar shape by the shape of a disc. It is preferably arranged perpendicular to the central axis Al.

In the first example illustrated, the microbiological filter means 32 has a peripheral edge 34 which has the same shape and the same dimensions as a section of the inner face of the side peripheral wall 20 of the main body 14. In the first example illustrated the peripheral edge 34 is intended to come to bear axially downward, directly or indirectly, against the annular bearing surface 28 of the main body 14. as will be seen later, in the first example

illustrated, peripheral edge 34 of the microbiological filter means 32 is preferably adapted to be clamped axially between the lower edge 30 of the cylindrical flange 26 of the cover 16 and the annular bearing surface 28 of the main body 14.

Microbiological control device comprises, inside a closed inner space 12, a nutritive layer 36 impregnated with a composition of a microbiological culture medium, the nutritive layer 36 being in contact with the microbiological filter means 32 .

In the illustrated embodiments, the nutritive layer 36 is a separate element from the microbiological filter means 32, while being in contact with the microbiological filter means 32. The nutritive layer 36 and the microbiological filter means 32 are brought into contact with one another within the microbiological control device once the latter assembled.

In this case, the nutritive layer 36 is preferably located with the conventions expressed above, below the microbiological filter means 32. In this case, the nutritive layer 36 is located in the second compartment 12b of the inner space closed 12. However, nothing prevents to provide that the nutritive layer is located, with the conventions expressed above, above the microbiological filter means 32. in this particular case, the nutritive layer advantageously comprises at least one chromogenic substrate and / or fluorogenic adapted to permit direct or indirect detection of an enzymatic activity or metabolic target microorganisms. The visual signal generated by said at least one substrate is visible through at least a portion of the thickness of the nutritive layer.

In the illustrated examples, the nutritive layer 36 has a substantially planar shape by the shape of a disc. The nutritive layer 36 has a peripheral edge 38 which preferably coincides with the peripheral edge 34 of the microbiological filter means 32. Thus, the nutritive layer 36 and the filtering means 32 have the same shape. In this way, in the first example illustrated, the peripheral edge 38 may come to bear axially downwardly against the annular bearing surface 28, by being inserted between the annular bearing surface 28 of the main body 14 and the edge device 34 of microbiological filter means 32. in the first example illustrated, the peripheral edge 38 of the nutritive layer 36 is preferably adapted to be clamped axially,

Within the meaning of the present invention, the nutritive layer 36 comprises a support containing a microbiological culture medium.

The carrier may be based on various absorbent compounds, preferably with very high water retention, such as rayon, cotton, natural cellulose fibers or chemically modified such as carboxymethyl cellulose, absorbent polymers or chemical superabsorbents such as polyacrylate salts, acrylate copolymer / acrylamide. This support may be impregnated with a microbiological culture medium in liquid form. This medium microbiological culture can advantageously be dehydrated, ie having an "Aw" (Activity of water, water activity) incompatible with microbial growth. Alternatively, the support may be coated or impregnated to dryness of a microbiological culture medium or constituents in powder form. Alternatively, the liquid saturant may

The term medium microbiological culture, a medium containing nutrients necessary for the survival and / or growth of microorganisms, including one or more of carbohydrates, including sugars, peptones, growth factors, the minerals and / or vitamins, etc ... In practice, the skilled person will choose the middle of microbiological culture based on target microorganisms according to criteria well known and accessible to the skilled person.

The nutritive layer 36 may contain any additive elements such as:

- one or more selective agents such as inhibitors or antibiotics to promote the growth and development of a species / strain specific microorganism rather than another;

- buffers, dyes.

In general, the nutritive layer 36 may in addition contain a substrate for detecting an enzyme activity or metabolic target microorganisms through a detectable signal directly or indirectly. For direct detection, this substrate may be bonded to a part making a label, fluorescent or chromogenic. For indirect detection, the nutritive layer according to the invention may comprise in addition a pH indicator, responsive to the change in pH induced by the consumption of substrate and revealing the growth of target microorganisms. Said pH indicator can be a chromophore or a fluorophore. May be mentioned as examples of chromophores neutral red, aniline blue, bromocresol blue. The fluorophores include, for example, 4-methylumbelliferone, hydroxycoumarin derivatives or derivatives of resorufin. Thus, the fluorescent substrate of PC-PLC preferentially used for the implementation of the method according to the invention is the 4-methyl-umbelliferyl-Choline phosphate (4 MU-CP).

According to a preferred embodiment of the invention, the microbiological culture medium of the nutritive layer 36 is in a configuration of providing microbiological control device prior to use, dried. In this case, after dry impregnation of the support of the nutritive layer through the middle of dehydrated microbiological culture, the nutritive layer 36 may be a calendering operation. Calendering, by pressure and the heating temperature generated, allows retention and stable maintenance in the time from among dehydrated microbiological culture in the support of the nutritive layer, ensuring the retention of nutrients and any additive elements in the nutritive layer.

Calendering the nutritive layer 36 also allows to obtain a smooth, flat surface of the nutritive layer. Calendering also enables acceleration of the rehydration of the nutritive layer with respect to a nutritive layer non-calendered, because of the compression of the nutritive layer it induces. In the case where the carrier is formed of fibers, such compression combined with the presence of the dehydrated medium within the nutritive layer 36, generates a sharp increase in the capillary power of the latter, causing its almost instantaneous rehydration. This can also contribute to a suction phenomenon of microbiological filtering means 32 disposed separate against its surface. The microbiological filter means 32 can thus be found pressed against the nutritive layer 36, thus ensuring the absence of space or reduce space between the two, in favor of a growth and / or optimum microbial survival (s) on the entire surface of microbiological filtration means 32. It is thus possible to avoid the presence binding means (e.g., avoid the presence of bonding layer) between the microbiological filter means 32 and the nutritive layer 36 are when they are separate. This represents a significant advantage, inasmuch as such connecting means slow down the passage of nutrients and optional additives elements of the nutritive layer 36 rehydrated to microorganisms present on the microbiological filter medium 32, thus reducing the growth and / or survival of these microorganisms. space between the two, in favor of a growth and / or optimum microbial survival (s) on the entire surface of microbiological filtration means 32. It is thus possible to avoid the presence of connecting means (e.g., avoid the presence of binder layer ) between the microbiological filter means 32 and the nutritive layer 36 are when they are separate. This represents a significant advantage, inasmuch as such connecting means slow down the passage of nutrients and optional additives elements of the nutritive layer 36 rehydrated to microorganisms present on the microbiological filter medium 32, thus reducing the growth and / or survival of these microorganisms. space between the two, in favor of a growth and / or optimum microbial survival (s) on the entire surface of microbiological filtration means 32. It is thus possible to avoid the presence of connecting means (e.g., avoid the presence of binder layer ) between the microbiological filter means 32 and the nutritive layer 36 are when they are separate. This represents a significant advantage, inasmuch as such connecting means slow down the passage of nutrients and optional additives elements of the nutritive layer 36 rehydrated to microorganisms present on the microbiological filter medium 32, thus reducing the growth and / or survival of these microorganisms. growth and / or optimum microbial survival (s) on the entire surface of microbiological filtration means 32. It is thus possible to avoid the presence of connecting means (e.g., avoid the presence of bonding layer) between the microbiological filter means 32 and nutritive layer 36 are when they are separate. This represents a significant advantage, inasmuch as such connecting means slow down the passage of nutrients and optional additives elements of the nutritive layer 36 rehydrated to microorganisms present on the microbiological filter medium 32, thus reducing the growth and / or survival of these microorganisms. growth and / or optimum microbial survival (s) on the entire surface of microbiological filtration means 32. It is thus possible to avoid the presence of connecting means (e.g., avoid the presence of bonding layer) between the microbiological filter means 32 and nutritive layer 36 are when they are separate. This represents a significant advantage, inasmuch as such connecting means slow down the passage of nutrients and optional additives elements of the nutritive layer 36 rehydrated to microorganisms present on the microbiological filter medium 32, thus reducing the growth and / or survival of these microorganisms. This can avoid the presence of connecting means (e.g., avoid the presence of bonding layer) between the microbiological filter means 32 and the nutritive layer 36 are when they are separate. This represents a significant advantage, inasmuch as such connecting means slow down the passage of nutrients and optional additives elements of the nutritive layer 36 rehydrated to microorganisms present on the microbiological filter medium 32, thus reducing the growth and / or survival of these microorganisms. This can avoid the presence of connecting means (e.g., avoid the presence of bonding layer) between the microbiological filter means 32 and the nutritive layer 36 are when they are separate. This represents a significant advantage, inasmuch as such connecting means slow down the passage of nutrients and optional additives elements of the nutritive layer 36 rehydrated to microorganisms present on the microbiological filter medium 32, thus reducing the growth and / or survival of these microorganisms.

The microbiological filter means 32 comprises a filter which is permeable to water and which retains the microorganisms, especially on its surface. In cases where the microbiological filter means 32 is distinct from the nutritive layer 36, microbiologically filtration means 32 is permeable to nutrients and optional additive elements in the nutritive layer 36 located under the microbiological filter means 32. This filter may comprise a porous body which can be made of a material which by its nature, its size, its steric arrangement has these properties. This porous body can have these properties through the pores of development.

The microbiological filter means 32 may for example be based on one or more materials, or derivatives of these materials, including latex, polytetrafluoroethylene, poly (vinylidene) fluoride, polycarbonate, polystyrene, polyamide, polysulphone, polyethersulfone, cellulose, a mixture of cellulose and nitrocellulose. Preferably the microbiological filter means 32 is in the form of a porous membrane permeable to nutrients and optional additives elements in the nutritive layer 36, and adapted to retain microorganisms on its surface. Preferably, the microbiological filter medium 32 covers the whole nutritive layer 36. We have found that water microfiltration membranes (and a liquid generally) currently on the market generally have the properties required for use as a microbiological filter means 32. They allow to obtain a very good tear strength during handling, a controlled porosity, a smooth surface, a thin layer and mostly strong hydrophilicity. Their color, usually white, to optimize the differentiation of colored colonies on their surface. The filtering capacity and the hydrophilicity of such a filtration membrane, in turn, are utilized to enable and optimize the passage of nutrients and possible elements additives present in the nutritive layer (optionally after rehydration) to an upper surface of the filtering means microbiological 32 while preventing or restricting migration in the opposite direction of the bacteria, yeast etc .. filtered to the upper surface of microbiological filtering means 32. for the purposes of the present application, the above filtration membranes are interchangeably referred to as "filter membranes", "microfiltration membranes" or "filter membranes" these terms are synonyms of each other. These filtration membranes are included in the group consisting of porous membranes. yeast etc .. filtered to the upper surface of microbiological filtering means 32. For the purposes of the present application, the above filtration membranes are interchangeably referred to as "filter membranes", "microfiltration membranes" or "membrane filters", these terms are synonymous to each other. These filtration membranes are included in the group consisting of porous membranes. yeast etc .. filtered to the upper surface of microbiological filtering means 32. For the purposes of the present application, the above filtration membranes are interchangeably referred to as "filter membranes", "microfiltration membranes" or "membrane filters", these terms are synonymous to each other. These filtration membranes are included in the group consisting of porous membranes.

The microbiological filter means 32 allows the passage of the nutrient medium or selective elements and reagents.

Advantageously, the filtering means has pores whose diameter is between 0.01 and 0.8 microns preferably from 0.2 microns to 0.6 microns so as to retain the bacteria, yeast and mold on its surface. According to a particular embodiment, the filtering means has pores whose diameter is between 0.25 microns and 0.6 microns, for example between 0.3 microns and 0.6 microns or between 0.4 microns and 0.6 microns. Alternatively, it may be a layer having no measurable pores as a dialysis membrane.

For example, a microbiological filtration medium can be a filter membrane "Fisherbrand ™ General Filtration Membrane Filters" marketed by Fisher Scientific Company LLC, 300 Industry Drive, Pittsburgh, PA 15275, USA, or a membrane filtration "Nitocellulose Membrane Filters "manufactured by Zefon International, Inc., 5350 SW lst Lane, Ocala, FL 34474, USA, or similar membranes.

In some embodiments, the nutritive layer can be integrated by means of microbiological filter 32, one for supporting the middle of microbiological culture. In this case, it goes without saying that the nutritive layer is in contact with the filtering means 32 microbiological.

Microbiological control device 10 according to the invention comprises an input port 40 for the liquid to be analyzed. The input port 40 allows, when the microbiological control device 10 is assembled such that the housing delimits a closed internal space, for example when the cover 16 is assembled with main body 14 to introduce the liquid to analyzing within the closed inner space defined by the enclosure, from outside the closed inner space 12.

In the embodiments shown, the input port 40 comprises an inner portion 42 which opens into the first compartment 12a of the closed inner space 12, and an outer portion 44 for connection to a container of liquid to be analyzed, the container being for example a syringe, a tube, a pocket, a funnel etc ..

In the examples shown, the input port 40 is arranged along the central axis Al, vertically. The input port is advantageously arranged on the cover 16, in this case for example the center of the transverse wall 22 thereof.

The inner portion 42 of the input port 40 may comprise a splitter 56 having a plurality of separate passages for the liquid to be analyzed. Such distributor 56 promotes distribution of the liquid to be analyzed, which is introduced through the input port 40, on a larger portion of the area of ​​microbiological filter medium 32. Particularly in the case of the configuration of the example of embodiment, the inner portion 42 of the input port 40 may comprise a splitter 56 which has orifices each of which opens at least partly in a radial direction relative to the central axis Al, the orifices preferably being spaced angularly around the central axis Al of the input port 40.

The outer portion 44 of connection 40 input port may include means for coupling with the container. The outer portion 44 of connection may itself present a funnel shape. The outer connecting portion 44 may comprise in addition to the mechanical securing means for securing the container to the input port 40.

Microbiological control device 10 includes a shutter 46 which, in the embodiments, is interposed between the inner portion 42 and outer portion 44 of the input port, so as to close the inlet port 40, preventing in a closed state of the shutter, any gas flow between the closed inner space 12 of microbiological control device 10 and the outside 40 through the input port.

Preferably, the input port 40 is a resealable port. In this case, which is illustrated, the shutter 46 may include a valve. Such a rod may preferably be brought successively several times from an open state to a closed state and vice versa.

In some cases, the shutter may comprise a waterproof membrane, and the shutter can be is brought into an open state by breaking the membrane. In the event, the membrane can not be closed. In this case, it may be provided to close the inlet port 40 by a secondary closure attached to the outer portion 44 of connection. Such a secondary shutter (not shown) may be formed for example by a plug, a sealed membrane or cap.

such a secondary shutter Note may also be provided in the case of presence of a valve type shutter as mentioned above. Such a secondary shutter allows for example to enhance gas-tightness of the valve, especially in air, and in particular the long-term sealing during a storage period of the device 10 before use.

In both cases, such a secondary shutter protects the input port from contamination during storage period of device 10 before use.

In the illustrated examples, the microbiological control device 10, when assembled, comprises only a single port fluid communication between the enclosed internal space 12 and the outside, here the input port 40. In the example illustrated, it is noted that the second compartment 12b of the internal closed space 12 is free from fluid communication with port outside the closed internal space. This does not prevent microbiological control device 10 may have multiple ports fluid communication with the inlet port 40, leading all in the first compartment 12a of closed internal space.

In the exemplary embodiment, the microbiological filter medium 32 has a small thickness compared to its extent. For example, the diameter of the filtration medium is greater than 50 millimeters, for example between 80 and 100 millimeters. Its thickness is in the order of a few millimeters, usually less than 5 millimeters.

Also, it is advantageous to provide microbiological control device 10 comprises a support 48 for microbiological filtration means 32 and 36 for the nutritive layer.

The holder 48 keeps the microbiological filter means 32 and the nutritive layer 36 in position 12a between the first compartment and the second compartment 12b.

In the first exemplary embodiment illustrated, the support 48 for microbiological filtration means 32 and the nutritive layer 36 comprises support walls 50 arranged in the second compartment 12b.

For example, the support walls 50 may be plane, each arranged in a radial plane containing the central axis Al. They may for example extend from the bottom wall 18 of the main body 14 and presenting a top edge 52 against which the microbiological filter means 32 and the nutritive layer 36 may come into abutment vertically downward, directly or indirectly. In the first example illustrated, each support wall 50 extends diametrically across the entire second compartment 12b, thus being transversely limited by two diametrically opposed portions of the peripheral side wall 20 of the main body 14. In this mode particular embodiment,

However, by themselves, the support walls 50 define therebetween, in the second compartment 12b, subdivisions of the second compartment 12b. Such supporting partitions 50 may be perforated to permit the flow of fluid on both sides of said baffles in the second compartment 12b. In the illustrated example, it is chosen to provide the support walls 50 with through opening 54 that allow fluid communication between two adjacent sub-divisions of the second compartment 12b which are separated by one of these support walls 50. These through openings 54 are optional. In the illustrated example, they are formed as slots which extend in the direction of the central axis A, from a low point located substantially at mid-height of the second compartment 12b, and they open out openly in the upper edge 52. These through-openings could present an entirely different geometry, and be for example made in the form of holes, in particular circular. They are not necessarily open out into the top edge 52.

In the example illustrated, the supporting walls 50 also help to mechanically reinforce the enclosure of the device, in particular to make it more resistant to a pressure difference between the inside and outside of the enclosure.

The support 48 for the microbiological filter means 32 could be realized differently. It could for example be realized in the form of a grid extending in a transverse plane perpendicular to the central axis Al. Such a grid could for example be supported in abutment on the bearing surface 28 of the main body 14. the support for the microbiological filter means 32 could be formed as one or more columns extending vertically in the direction of the axis Al from the transverse end wall 18 of the main body 14. the support means for the microbiological filter 32 could also be embodied as one or more brackets extending transversely from an inner face of the peripheral sidewall 20.

In the second example illustrated in FIGS. 5 to 7, the support 48 for the filtering means comprises a grid 49. This grid may be formed by intersecting a son beam or by a crossed bars beam. In the example illustrated in FIGS. 5 to 7, the grid is formed by a perforated plate which extends perpendicularly to the central axis A, between the first compartment and the second compartment. This grid 49 is in the illustrated case made in one piece with the peripheral side wall 20 of main body 14. It is understood that the grid 49 in the form of perforated plate provides better support for the microbiological filtration means 32, particularly if the -ci is somewhat rigid. The result is a better flatness of the filtration means 32 microbiological and nutritional layer 36

In the example illustrated, the plate extending across the main body 14 throughout the entire internal diameter thereof. The plate has an outer peripheral portion 51, annular, extending radially towards the central axis A from an inner cylindrical surface of the peripheral side wall 20. The outer peripheral portion 51 of the plate is full, so imperforate. The plate has a perforated central portion, the center of the outer peripheral portion, which forms the gate 49. The upper face of the perforated central portion 49 is downwardly offset with respect to an upper surface of the outer peripheral portion. In this way, the outer peripheral portion 51, defines, in the upper face of the plate, a recess whose diameter corresponds to that of the perforated central portion 49. In the example illustrated, the filtering means 32 and the nutritive layer 36, have an outer diameter which is equal to or less than the diameter of the recess. Thus, the filtering means 32 and the nutritive layer 36, can be received in the recess, being wedged radially into the recess. It is noted, that in this second embodiment, the filtering means 32 and the nutritive layer 36, are not pinched between the lid 16 and the main body 14, unlike the first exemplary embodiment.

It is noted in Figure 6, seen from below, the second embodiment includes, in the second compartment 12b, partitions 53 which, apart from the direct support function of filtration means, have the same functions, and substantially the same geometry as the support walls of the first exemplary embodiment.

The support 48 is designed to form a limited resistance to negligible to the flow of fluids between the first and the second compartment from the closed internal space. In the case of a perforated plate, for example to ensure that the total accumulated area in projection along the central axis Al, perforations 55 is at least 30% of the area of ​​the filtering means 32, preferably at least 50% of the

area of ​​the filtration means. The perforated plate has a plurality of perforations 55, distributed within a circumscribed circle (smallest circle containing all the perforations) which is in correspondence with at least 50%, preferably at least 70% of the area of ​​the medium filtration 32. in the examples considered, the perforations 55 are in number larger than 20, preferably greater than 50. However, with larger perforations, and possibly of different geometry, for example star, range, etc., a lower number of perforations could be utilisé.- the support 48 for the microbiological filter means 32 is, in the example shown, made in one piece with the main body 14. However, this support may be made in the form of ' one or more independent parts. Such parts may be simply placed inside the second compartment 12b, or may be assembled to the main body 14, for example by gluing, by welding, by snap-fastening or by interlocking.

In the illustrated example, it is noted that the nutritive layer 36 is arranged between the microbiological filter means 32 and the support 48 for the filtration means.

Advantageously, it is expected that the nutritive layer 36 is locally clamped between the microbiological filter medium 32 and its support 48. For example, the cover 16 may comprise support elements, for example corresponding to the upper edge of one or partitions holder 50, so that when the microbiological control device is assembled, the microbiological filter means 32 and the nutritive layer 36 find themselves clamped between the support elements of the cover 16 and the support 48. in the example shown the distributor 56 has, on an underside, such support means to the center of the microbiological control device, clamping the filter means 32 and microbiological nutrient layer 36 against the support 48.

In the example shown, the volume of the second compartment 12b of the internal closed space 12 is greater than the volume of the first

compartment 12a from the closed internal space. Preferably, the volume of the second compartment 12b of the closed internal space 12 is at least twice, preferably at least three times the volume of the first compartment 12a of the closed inner space. In one embodiment, for a device for the analysis of a sample of 100 milliliters, the volume of the second compartment 12b of the closed internal space 12 is for example of at least 100 ml, preferably greater than 100 mL and less than 150 milliliters, to be able to contain the entire volume of a liquid to be analyzed. The total volume of the closed inner space defined by the enclosure is for example between 120 and 300 ml, the total volume being for example 150 milliliters.

In a provision of configuration microbiological control device 10 prior to use, the obturator 46 is in a closed state to close the inlet port 40 and the closed inner space 12 in a sealed manner to the air.

In this provision of configuration, microbiological control device 10 is sealed, without gas communication possible between the closed inner space 12 defined by the enclosure and the outside. In this provisioning configuration, microbiological filtration means 32 and the nutritive layer 36 are contained inside this closed internal space 12 defined by the enclosure, thus forming a microbiological control device ready to use for filtering the liquid to be analyzed in order to collect possible microorganisms on the microbiological filter means 32, and to allow the development of such micro-organisms for detection, a counting of characterization and / or identification.

Moreover, in this configuration of providing microbiological control device 10 prior to use, an absolute gas pressure within the enclosed internal space is at a reduced initial pressure value so that the device is capable of creating a suction through the input port during a first opening of the shutter 46.

It follows from the preceding two paragraphs that in this configuration providing microbiological control device 10 prior to use, thus before introduction of a sample in this closed internal space 12 defined by the enclosure, the filtering means microbiological 32 and the nutritive layer 36, which comprises a composition of a microbiological culture medium, are contained inside this closed internal space 12 defined by the enclosure and the absolute gas pressure inside the space internal closed is reduced initial pressure value so that the device is adapted to create a suction through the input port during a first opening of the shutter 46.

For this, the initial reduced pressure value of the absolute gas pressure within the enclosed internal space (12), reduced to a temperature of 25 ° C is strictly less than the standard atmospheric pressure at 25 ° LBAR vs.

In practice, the suction phenomenon will result in an entry in the internal space of the device, a predetermined volume of liquid more rapidly during the first opening of the shutter, that in the case where the initial pressure in the inner space is equal to atmospheric pressure.

Note that it is not necessary to accurately know the precise value of the reduced initial pressure. Indeed, this value is primarily determined to be sufficient for sucking at least in part or in whole, a predetermined volume of the test sample within the device.

Preferably, this value is determined to be sufficient for the device to be capable of sucking in all a predetermined volume of the test sample within the device, without the need of subjecting the sample to analysis for a pressure higher than the standard atmospheric pressure to make it enter the interior of the device.

Preferably, this reduced initial pressure value is low enough to allow the entry into all of a predetermined volume of

the sample to be analyzed into the interior without evacuating fluid from the inner space at the input of the predetermined volume of the sample to be analyzed. This ensures an easy entry of the entire sample into the device. This also helps to prevent any propagation of elements originally contained in the device, in particular the culture medium elements outwardly upon entry of the sample into the device.

The skilled person may, by an initial assessment, supplemented to some tests, determining a reduced desired initial pressure to the device, depending on the conditions envisaged for the implementation of the device (total volume of the internal closed space 12 defined by the enclosure of the device, sample volume, temperature and pressure during the implementation of the device, ...) ■

Conveniently, one can evaluate the value of the reduced desired initial pressure as follows. Consider the total volume VT of the closed inner space 12 defined by the enclosure. then predetermines a predetermined volume VE of the test sample that is desired to be introduced into the device 10 to perform the analysis. It then derives the final free volume VL in the internal space, after the input of the predetermined volume of the test sample in the inner space. This final free volume VL is therefore the total volume VT of the closed inner space 12 defined by the enclosure from which is subtracted the predetermined volume VE of the test sample that is desired to be introduced into the device 10 to perform the analysis:

VL = VT - AND

is then applied, by way of approximation, the ideal gas law with the terms of variations in the internal closed space 12 defined by the enclosure between the time just before the input of the sample and the time just after the input of the sample, assuming that only the liquid containing the sample is introduced, without any significant change in temperature. This entry of the sample results in a change in pressure from the reduced initial pressure value Pi, which is the value of the absolute gas pressure inside the closed inner space in the

provision of configuration, to a final value Pf, which is the absolute gas pressure value within the internal space, after the input of a predetermined volume of sample to be analyzed.

We therefore obtain the relation

VL = pf pf x x (VT - VE) = Pi x VT

Which give

Pi = Pf x (VT - VE) / VT = Pf x VL / VT

It is therefore deduced that in the provision of configuration microbiological control device 10 prior to use, an absolute gas pressure within the enclosed internal space 12, called the reduced initial pressure, is preferably strictly lower than the pressure atmospheric multiplied by the ratio of the final free volume in the inner space after the input of a predetermined volume of the test sample divided by the total volume of the internal space.

Conveniently, one can determine arbitrarily the value of the standard atmospheric pressure to 1 bar at 25 ° C.

In practice, it is generally considered that a sample must have a VE volume of at least 20 milliliters, preferably at least 50 milliliters, more preferentially at least 100 milliliters. However it is generally considered that a sample must have a VE volume of 300 milliliters or less, preferably 200 ml or less, more preferably 150 mL or less.

In the case of a device of which the total volume of the internal space VT is 150 mL, and a sample volume of 100 milliliters VE, fast calculated above provides the desired reduced initial pressure, for an absolute gas pressure within the internal closed space 12 in the configuration of provision of the device before use, strictly less than 333 millibars absolute. However, in practice, preference will provide an initial strictly reduced pressure below 300 millibars absolute, to reflect the offset related approximations between the assumptions and experimental reality. More preferably, it is preferable providing a strictly lower initial pressure 200 millibars absolute, particularly for rapid entry of the

Note that, for a total volume VT of 300 mL of the internal space of the device, a desired reduced initial pressure is thus determined strictly less than 666 millibars absolute, preferably strictly less than 600 millibars absolute, more preferentially less than strictly 400 millibars absolute.

Note that the above values ​​are guidelines, including for a given device and the conditions of implementation data. It will indeed, any interest in the initial reduced pressure in the device is actually less than the values ​​above.

In practice, these values ​​will be the basis for the development of a device according to the invention and the manufacturing conditions for the proper functioning of the device will be easily determined with a few routine tests.

Also, the above values ​​can be measured by connecting a pressure gauge at the entrance of the port of entry, as close shutter 46, even if the result is uncertainty about the real value of the reduced initial pressure including if this uncertainty is 50 millibars.

This means that, during the preparation of microbiological control device, an at least partial vacuum is created in the closed internal space. This at least partial vacuum may have been made, for example by a vacuum assembly, or at least under a pressure less than or equal to the desired reduced initial pressure, in any case strictly less than 1 bar at 25 ° C, or by depressurization the closed inner space after assembly of the microbiological control device.

It is understood that, in this configuration of providing microbiological control device 10 prior to use, the closed inner space is isolated from any external suction source. It is therefore understood the need for the speaker and the input port 40 in its closed state are gas tight, particularly airtight. This is achieved by means of any known in the art.

In the example illustrated, the cover 16 and the main body 14 are thus sealingly assembled to the air.

The assembly may be a removable assembly, allowing an opening of microbiological control device without destruction after use, for example to remove microbiological filter means 32. A releasable connection can be achieved for example by means of complementary screw threads arranged respectively on the lid 16 and the main body 16. in the illustrated configuration, such complementary threads (not shown) may be arranged respectively on an outer face of the cylindrical flange 26 of the cover 16 and on an inner face of the upper end of the peripheral side wall 20 of the main body 14. another possible example of releasable connection may be obtained by a bayonet assembly system. Yet another example of

The assembly may be a non-detachable assembly, not allowing an opening of microbiological control device 10 without destruction after use, for example by gluing, by welding or by riveting.

To ensure the required sealing gas, including air, may be provided, particularly in the case of a removable assembly, one or more seals (not shown) between the main body 14 and cover 16.

In the configuration of providing microbiological control device prior to use, the microbiological culture medium of the nutritive layer 36 is preferably dehydrated. It is then expected that this microbiological culture medium is rehydrated at the time of use. This rehydration can be performed by analyzing the liquid itself.

Indeed, the microbiological filter means 32 and the nutritive layer 36 are arranged so that any fluid exchange between the first compartment 12a and the second 12b compartment from the closed inner space takes place through the filtering means 32 microbiological and nutritive layer 36. it is thus possible that it is not possible for a fluid bypass or the microbiological filter means 32 or the nutritive layer 36 to pass from the first chamber 12a to the second compartment 12b. In the illustrated embodiment, this follows from the fact that the microbiological filter means 32 and the nutritive layer 36 extend across the entire section of the '

Advantageously, there may be provided a water-absorbent material is arranged in the second compartment. In the example illustrated, such a material may be arranged in one, several, or all among the subdivisions of the second compartment 12b between the supporting walls 50. An absorbent material may be based on various absorbent compounds, preferably very strong power to water retention, such as rayon, cotton, natural cellulose fibers or chemically modified such as carboxy-methyl cellulose, chemical absorbent polymers or super-absorbent such as polyacrylate salts, acrylate copolymer / acrylamide. Of such materials can thus be obtained from the company Technical Absorbents Limited, 1 Moody Lane, Great Coates, Grimsby, DN31 2SS, United Kingdom

The enclosure of microbiological control device can be advantageously made of polymeric material. However, it is also possible to achieve in other materials, including at least partially of glass. In the example illustrated, the main body 14, the cover 16 and the support 48 may be made of the same material or of different materials.

Preferably, the enclosure of microbiological control device comprises at least one transparent portion. In particular, this transparent portion can be arranged so that an observer can see at least a portion of the upper face of microbiological filter medium 32 which faces the first compartment 12a. Preferably, this transparent portion is provided so that an observer can see the entire upper face of the microbiological filter medium 32 which faces the first compartment 12a. Indeed, it is on this front that will be visible from any micro-organisms after incubation. In the example illustrated, the transparent portion of the chamber is therefore preferably arranged at least in the transverse wall 22 of the cover 16. The entire cover 16 may be transparent. In some embodiments, we provide that the entire enclosure is a transparent material. The transparent portion of the chamber is for example made of poly (methyl methacrylate) (PMMA) or glass.

A microbiological control device as thus described above is intended to be used in a method for controlling a fluid to be analyzed may contain at least one microorganism.

In such use, it is previously provides a microbiological control device in a configuration providing before use. As seen above, in this configuration, the microbiological control device has the microbiological filter means 32 and the nutritive layer 36 which are locked in the closed inner space 12 in a sealed manner, and in this space closed internally, prevails a negative pressure level which corresponds to the initial reduced pressure in any case at an absolute gas pressure within the enclosed internal space, reduced to a temperature of 25 ° C, strictly less than 1 bar .

In order to provide microbiological control device for controlling a fluid to be analyzed may contain at least one microorganism, so we must first provide a microbiological testing device comprising, as described above:

- an enclosure intended to define a closed inner space 12 closed for receiving the liquid to be analyzed, for example in the form of a main body 14 and a cover 16;

- Microbiological filtration means 32 intended to be arranged in the closed inner space 12 and to separate in the closed internal space, a first compartment 12a of a second compartment 12b of the closed internal space;

- an input port 40 for the liquid to be analyzed provided to open into the first compartment 12a of the closed internal space, the input port may for example comprise an inner portion 42 provided to open into the first compartment 12a of 'closed internal space, and an outer portion 44 of connection.

Furthermore, the provision of method before use comprises providing a nutritive layer 36, adapted to be received within the closed inner space and comprising a composition of a microbiological culture medium, the nutritive layer 36 being intended to be in contact with the filtering means. As seen above, this nutritive layer 36 may be separate from the microbiological filter means 32 or, alternatively, may provide that the nutritive layer and the microbiological filter means are integrated with each other.

According to the invention, the provision of method of microbiological control device in a configuration of providing comprises, before use so before any connection to a container of liquid to be analyzed, successively and in this order:

- a depressurization step for lowering the absolute gas pressure within the enclosed internal space 12;

- a closing step to close the internal space 12 closed in sealed manner to the air.

It is noted that when the depressurization step, the microbiological control device 10 comprising the elements set forth above may be already assembled, such that the chamber is closed and contains the above elements. In this case, the depressurization step may be achieved by connecting the closed inner space 12 of microbiological control device to a suction source, for example a vacuum pump, for example through the input port 40, the latter then being in an open state. Therefore, the pressure is reduced to the desired initial reduced pressure which is, in any case, reduced to a temperature of 25 ° C, strictly less than 1 bar.

In another embodiment, the depressurization step may be concomitant with a step of assembling. Indeed, in the example shown may be provided such that the cover assembly 16 of the main body 14, which closes the chamber and thus define the closed inner space 12 may be at a pressure absolute gas at or below the reduced desired initial pressure, or in particular a pressure reduced to a temperature of 25 ° C, strictly less than 1 bar.

In the first case, the closure step may consist in closing an input port of the valve 40 or the installation of a waterproofing membrane, as it is still at an absolute gas pressure equal or less than the desired reduced initial pressure. In the second case, the closure step may consist in the assembly of the lid 16 of the 14 sealingly main body for closing the enclosure. In this case, the input port shutter 40 is preferably first in a closed state.

Thus, there is obtained a microbiological control device 10 in a provisioning configuration in which, within the closed inner space 12 defined by the enclosure, there is the microbiological filter means 32 and the nutritive layer 36 , the closed internal space 12 is at an initial predetermined level of depression, called reduced initial pressure, which corresponds to a gas pressure in the closed inner space lower than a predetermined threshold, the predetermined threshold being itself strictly less than standard atmospheric pressure, the predetermined threshold being for example for example 200 millibars absolute pressure reduced to 25 ° C.

Note that, in the provision of configuration, microbiological control device can be stored, transported, etc. .... and that this provision of configuration, no liquid to be analyzed has been introduced into the 'closed internal space 12 of microbiological control device.

Using a microbiological control device according to the invention corresponds to the introduction, within the closed inner space 12, the liquid to be analyzed, by the input port 40. This introduction is generally the connecting a container, wherein the liquid to be analyzed, with the input port 40. such a connection may take various forms, simply assuming that a fluid communication is established between the container and the input port 40. preferably, this connection is a tight connection fluid and preferably gas-tight, in particular air. This connection may comprise a mechanical linkage between the container and the input port 40.

In this way, the use of a microbiological control device according to the invention comprises the steps of:

- connecting a container of liquid to be analyzed to the input port 40, particularly in the exemplary embodiment the outer portion 42 of connection of the input port 40;

- opening the shutter 46 from the input port to allow passage of the liquid to be analyzed from the container to the closed inner space 12 of microbiological control device.

This step open the shutter 46 of the input port is a first opening of the closure in a closing step to close the internal space 12 closed in a sealed manner during the process of making available.

It is at this stage that the initial predetermined level of depression plays a particularly important role. Indeed, the presence of this depression is favorable for the introduction of liquid to be analyzed in the closed inner space 12 of microbiological control device. This is partly due to the phenomenon of suction exerted on the liquid to be analyzed if it is initially for example at atmospheric pressure. This is due on the other hand the fact that the predetermined level of vacuum results in the presence in small quantities of gas in the microbiological control device prior to introducing the liquid to be analyzed, so that the microbiological control device should not, during the introduction of the liquid to be analyzed, evacuating a corresponding quantity of gas.

It is noted that during this step of using the microbiological control device in which the shutter opening allows the passage of liquid to be analyzed from the container to the closed inner space 12, the closed internal space 12 may be isolated from any external suction source. Indeed, the suction is advantageously obtained thanks to the initial reduced pressure in the device before the first opening of the device in a closure stage for closing the internal space 12 closed in sealed manner to the air during the process of provision.

In this way, the introduction of the liquid to be analyzed in the microbiological control device 10 according to the invention, through the input port 40, enables the liquid to be introduced firstly into the first compartment 12a of 'closed internal space 12, the liquid to be analyzed then naturally engaging the microbiological filter means 32. the liquid to be analyzed is filtered through the filtration microbiological means 32, so that at least some of any microorganisms, including those targeted for the intended control, are retained by the microbiological filter means 32. in contrast, the liquid portion of the liquid to be analyzed migrates towards the second compartment 12b of the closed inner space 12. for this, it is understood thatit is advantageous for the microbiological control device is, for this step at least in the orientation shown in the figures, the second compartment 12b of the closed inner space 12 located below the first compartment, both compartments being separated one another by the microbiological filtration means 32 which, in the example shown, extends in a plane which is then horizontal.

The liquid to be analyzed allows rehydration of the nutritive layer 36.

As the nutritive layer 36 is in contact with the filtration means, nutrients and possible elements additives thereof may migrate towards the microorganisms that are retained by the microbiological filter means 32. In this way, whereupon microbiological control device 10 is placed in an environment, including temperature, favorable can be obtained by incubation of the microorganisms inside the microbiological control device 10 itself, without the need to open the -Cl, in any case without the need to remove the microbiological filter means 32 of the enclosure of microbiological control device 10.

Thus, the use of a microbiological control device 10 according to the invention can, after the step of introducing a liquid to be analyzed within the enclosed internal space 12 of microbiological control device comprise the subsequent steps of:

- closing the shutter 46 of the input port 40;

- incubating in the microbiological control device, any microorganism initially contained in the liquid to be analyzed.

After such incubation period, the use can include a subsequent monitoring step of detecting, counting, identifying and / or visually characterize a potential microorganism initially contained in the liquid to be analyzed, including vision through to a transparent portion of the chamber of the microbiological control device. Again, this monitoring step can be performed without it being necessary to open the microbiological control device 10, the microbiological filter medium 32, on which there are any micro-organisms, therefore remaining inside the closed inner space of microbiological control device 10.

The invention is not limited to the examples described and shown since various modifications can be made without departing from its scope.

CLAIMS

1 - microbiological control device (10) for controlling a fluid to be analyzed may contain at least one microorganism of the type comprising:

- a closed inner space (12) delimited by an enclosure for receiving the liquid to be analyzed;

- a microbiological filter means (32) arranged in the closed inner space (12) and separating in the closed internal space, a first compartment (12a) of a second compartment (12b) from the closed internal space;

- one input port (40) for the liquid to be analyzed, the input port opening into the first compartment (12a) of the closed internal space,

characterized in that the microbiological control device (10) comprises, within the enclosed internal space, a nutritive layer (36) comprising a composition of a microbiological culture medium, the nutritive layer (32) being contact with the filtering means (32), in that the port of entry (40) of microbiological control device comprises a shutter (46), and in that, in a configuration providing microbiological control device (10) before use:

- the shutter (46) from the input port (40) is in a closed state to close the port of entry (40) and the closed inner space (12) airtight manner;

- the absolute gas pressure within the enclosed internal space (12), reduced to a temperature of 25 ° C is strictly less than the standard atmospheric pressure LBAR at 25 ° C, so that the device is adapted creating a suction through the input port during a first opening of the shutter (46).

2 - microbiological control device according to claim 1, characterized in that, in the configuration of providing microbiological control device (10) before use, the closed inner space (12) is isolated from any source of external ' aspiration.

3 - microbiological control device according to any one of the preceding claims, characterized in that, in the configuration of providing the device (10) before use, microbiological culture medium of the nutritive layer (36) is dehydrated.

4 - microbiological control device according to any one of the preceding claims, characterized in that the microbiological control device (10) comprises a support (48) for the filtration means (32) and the nutritive layer (36).

5 - Device for microbiological control according to claim 4, characterized in that the nutritive layer (36) is clamped locally between the filtering means (32) and the support (48) for the filtration means (32).

6 - Device for microbiological control according to any one of Claims 4 or 5, characterized in that the carrier (48) for the filtration means (32) comprises support walls (50) arranged in the second compartment (12b) .

7 - microbiological control device according to any one of claims 4 or 5, characterized in that the carrier (48) for the filtration means (32) comprises a grid (49) extending across the space internal closed, between the first compartment (12a) and the second compartment (12b).

8 - microbiological control device according to any one of the preceding claims, characterized in that a water-absorbent material is arranged in the second compartment (12b).

9 - Device for microbiological control according to any one of the preceding claims, characterized in that the obturator (46) from the input port (40) comprises a valve.

10 - Microbiological control device according to any one of the preceding claims, characterized in that the enclosure of microbiological control device comprises at least one main body (14) defining at least in part the second compartment (12b), and comprises a cover (16) which delimits at least partly the first compartment (12a), the main body and the lid being formed of separate components assembled to one another to form the microbiological control device.

11 - Microbiological control device according to any one of the preceding claims, characterized in that the enclosure of microbiological control device comprises at least one transparent portion.

12 - Device for microbiological control according to any one of the preceding claims, characterized in that the port of entry (40) comprises a distributor (46) comprising several separate passages for the liquid to be analyzed.

13 - Microbiological control device according to any one of the preceding claims, characterized in that, in the configuration of providing microbiological control device (10) prior to use, an absolute gas pressure inside the space internal closed (12) is such as to allow the input of a predetermined volume of the sample to be analyzed without removal of fluid from the inner space at the entrance to the input of a predetermined volume of sample to be analyzed.

14 - Microbiological control device according to any one of the preceding claims, characterized in that, in the configuration of providing microbiological control device (10) prior to use, an absolute gas pressure inside the space internal closed (12) is strictly less than the standard atmospheric pressure multiplied by the ratio of the final free volume in the inner space after the input of a predetermined volume of the test sample divided by the total volume of inner space.

15 - Microbiological control device according to any one of the preceding claims, characterized in that, in the configuration of providing microbiological control device (10) prior to use, an absolute gas pressure inside the space internal closed (12), reduced to a temperature of 25 ° C is strictly less than 600 millibars absolute, preferably strictly less than 300 millibars absolute, more preferably strictly less than 200 millibars absolute.

16 - A method of providing a microbiological control device for controlling a fluid to be analyzed may contain at least one microorganism of the type comprising providing a microbiological control device (10) comprising:

- an enclosure intended to define a closed inner space (12) for receiving the liquid to be analyzed;

- Microbiological filtration means (32) adapted to be arranged in the closed inner space and to separate in the closed internal space, a first compartment (12a) of a second compartment (12b) of the closed inner space ;

- one input port (40) for the liquid to be analyzed, the input port opening into the first compartment (12a) of the closed inner space (12),

characterized in that the method comprises providing a feeder layer (32) adapted to be received within the closed inner space (12) and comprising a composition of a microbiological culture medium, the nutritive layer (36) being in contact with the filtering means (32),

and in that the method comprises, before connecting the microbiological control device (10) to a container of liquid to be analyzed, successively and in this order:

- a depressurization step for lowering the absolute gas pressure within the enclosed internal space (12), reduced to a temperature of 25 ° C, strictly less than 1 bar;

- a closing step to close the closed inner space (12) sealed to the air.

17 - Process according to claim 16, characterized in that the depressurization step lowers the absolute gas pressure within the enclosed internal space (12) to a value such as to allow the input of a predetermined volume of the sample to be analyzed without removal of fluid from the inner space at the entrance to the input of a predetermined volume of the sample to be analyzed.

18 - A process for microbiological testing according to any one of claims 16 or 17, characterized in that the depressurization step lowers the absolute gas pressure within the enclosed internal space (12) to a value strictly less than standard atmospheric pressure multiplied by the ratio of the final free volume in the inner space after the input of a predetermined volume of the test sample divided by the total volume of the internal space.

19 - A process for microbiological testing according to any one of claims 16 to 18, characterized in that the depressurization step lowers the absolute gas pressure within the enclosed internal space (12), reduced to a temperature 25 ° C, to a value strictly less than 600 millibars absolute, preferably strictly less than 300 millibars absolute, more preferably strictly less than 200 millibars absolute.

20 - Use of a microbiological control device as claimed in one of claims 1 to 15 in a method for controlling a fluid to be analyzed may contain at least one microorganism.

21 - Use according to claim 20, characterized in that it comprises the steps of:

- connecting a liquid container to be analyzed in the input port (40); - opening the shutter (46) from the input port (40) to allow passage of the liquid to be analyzed from the container to the closed inner space (12).

22 - Use according to claim 21, characterized in that it comprises the further steps of:

- close the shutter (46) from the input port (40);

- disconnect the liquid container to be analyzed;

- incubating in the microbiological control device (10), any microorganism initially contained in the liquid to be analyzed.

23 - Use according to claim 22, characterized in that it comprises a further step to detect, enumerate, identify and / or characterize a possible visually microorganism initially contained in the liquid to be analyzed by vision through a portion transparent enclosure microbiological control device (10).