FORM 2
THE PATENT ACT, 1970
(39 OF 1970)
AND
THE PATENT RULES, 2003
COMPLETE SPECIFICATION
(See section 10; rule 13)
1. TITLE OF THE INVENTION
ANTIBIOTIC DISC DISPENSING DEVICES
2. APPLICANT:
(a). Name: Span Biotronics Private Limited
(b). Nationality: Indian
(c). Address: 2, Vatika
14, Bapista Road Vile Parle (West) Mumbai - 400056 Maharashtra, India
3. PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed;

FIELD OF THE INVENTION
The invention relates to a disc dispensing apparatus comprising a plurality of individual disc dispensers for linearly dispensing at least one sensitivity disc at a pre-defined position on the receiver. The invention further relates to a method of dispensing the sensitivity discs linearly on the receiver.
BACKGROUND OF THE INVENTION
In antimicrobial sensitivity testing, sensitivity discs impregnated with substances such as antibiotics are dispensed onto the surface of the culture medium in receiving containers such as a Petri dish. The sensitivity discs particularly comprise circular pieces of absorbent materials such as a blotting paper which has a thickness of about 1 mm. The discs are conventionally available in a stack of about 50 discs in a cylindrical elongated cartridge, wherein the discs are based at one end of the cartridge by means of an internal coil spring.
Numerous sensitivity disc dispensing devices are known in the art for dispensing discs from cartridges. Traditionally, the sensitivity discs are dispensed either by tweezers, pen like cartridges containing the discs or small handheld dispensers. It is however observed that the manual dispensing by tweezers, pen like cartridges as well as handheld dispensers is not accurate and suffers from the disadvantage that the positioning of the discs on the culture medium is not sufficiently precise. They do not allow reproducible distances and desired sensitivity zone diameters between the dispensed discs. The reason for this is that, most dispensers allow the discs to drop freely under gravity for a short distance onto the culture medium, resulting in random positioning of the discs on to the surface of the medium. This can lead to waste of the

Petri dish area or smaller than desired zones between the dispensed sensitivity discs. Besides, these devices are not very user friendly and consume a lot of time of the skilled personnel.
The disc dispensers known in art further include a variety of automatic disc dispensing devices provisioned to simultaneously dispense a plurality of discs in a predetermined pattern from the respective cartridges.
A patent application 503/MUM/2006 discloses an automatic disc dispensing apparatus equipped with a rotary dispensing mechanism to dispense multiple discs simultaneously in a predetermined concentric pattern.
The automatic disc dispensing devices provide for reproducible distances between the discs and desired sensitivity zone diameters. However, they are expensive and have the drawback of becoming dysfunctional even if one of the cartridges is empty or faulty.
Further, some known automated disc dispensing devices comprise several individual dispensers arranged in a concentric pattern in two rings on a dispenser plate. Such devices generally work on the principle of rotary motion for dispensing the sensitivity discs. In such dispensers, the multiple discs are effectively dispensed from the individual dispensers located in the outer ring of the device. However, there is a problem observed during the simultaneous dispensing of the discs from the individual dispensers positioned in the inner ring of the device and therefore such automatic dispensing devices are not feasible in sensitivity assays.
Hence there is a need to develop a disc dispensing apparatus which overcomes some or all the above drawbacks observed in the prior art disc dispensers. There is a further need to develop a disc dispensing apparatus which is simple, easy to operate, adapted

for detection and correction of malfunctions occurring during the dispensing process and which involves reduced manufacturing costs. There is a further need to develop a disc dispensing apparatus which provides for reproducible distances between the dispensed discs and which provides for uniform sensitivity zone diameters between the dispensed discs to ensure the accuracy of the test results.
SUMMARY OF THE INVENTION
A disc dispensing apparatus for linearly dispensing at least one sensitivity disc, the
disc dispensing apparatus comprising:
a top portion, wherein the top portion comprises a plurality of individual disc
dispensers embedded in the top portion and wherein each individual disc dispenser
comprises a first surface for releasing at least one sensitivity disc from a disc-loaded
cartridge and a hollow well for dispensing the sensitivity disc at a pre-defined
position on a receiver; and,
a peripheral side wall to position the disc dispensing apparatus on the receiver,
wherein the peripheral side wall is coupled to the top portion.
A method of linearly dispensing a sensitivity disc from a disc dispensing apparatus to a receiver, the method comprising steps of:
a. receiving at least one disc-loaded cartridge on at least one individual
disc dispenser located on a top portion of the disc dispensing
apparatus;
b. moving the disc loaded cartridge against a first surface of the
individual disc dispenser to release at least one sensitivity disc from
the disc-loaded cartridge; and,
c. dispensing the released sensitivity disc to the receiver through a
hollow well of the at least one disc dispenser on the receiver.

The invention further relates to a use of the disc dispensing apparatus in linearly dispensing at least one sensitivity disc to a receiver during antimicrobial sensitivity assays.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the invention, reference should now be made to the embodiments illustrated in greater detail in the accompanying drawings and described below by way of embodiments of the invention.
FIGURE 1 illustrates a top view of a receiver wherein the sensitivity discs are dispensed in accordance with an embodiment of the invention.
FIGURE 2 illustrates an isometric front view of the disc dispensing apparatus showing the top portion and the peripheral side wall with the plurality of individual disc dispensers embedded on the top portion in accordance with an embodiment of the invention.
FIGURE 3 illustrates a top view of the disc dispensing apparatus depicting the plurality of individual disc dispensers in a concentric pattern on the top portion of the disc dispensing apparatus in accordance with an embodiment of the invention.
FIGURE 4 illustrates an isometric bottom view of the disc dispensing apparatus in accordance with an embodiment of the invention.
FIGURE 5 illustrates an isometric front view of the optional base station which can be coupled to the disc dispensing apparatus in accordance with an embodiment of the invention.

FIGURE 6 illustrates an isometric view of the disc dispensing apparatus coupled to the base station to position and align a receiver during the dispensing process in accordance with an embodiment of the invention.
It is to be understood that the drawings are not to scale and are schematic in nature. In certain instances, details which are not necessary for an understanding of the present invention or which renders other details difficult to perceive, may be omitted. It should be understood, of course, that the invention is not necessarily limited to the particular embodiments illustrated herein.
DETAILED DESCRIPTION OF THE INVENTION
In describing the embodiments of the invention, specific terminology is used for the sake of clarity. However, it is not intended that the invention be limited to the specific terms so selected and it is to be understood that each specific term includes all technical equivalents that operate in a similar manner to accomplish a similar purpose.
The invention relates to a disc dispensing apparatus for linearly dispensing at least one sensitivity disc on a receiver. The invention further relates to a method of dispensing a sensitivity disc from a disc dispensing apparatus on a receiver and a use of the disc dispensing apparatus in antimicrobial sensitivity testing.
The disc dispensing apparatus has a top portion and a peripheral side wall which is coupled to the top portion. The peripheral side wall allows the positioning of the disc dispensing apparatus on the receiver. The top portion of the disc dispensing apparatus includes a plurality of individual disc dispensers embedded therein. Each of the individual disc dispensers has a first surface provisioned to release at least one sensitivity disc from the disc loaded cartridge. The disc loaded cartridge is pushed

against the first surface to release at least one sensitivity disc from the disc loaded cartridge to the receiver. Preferably the lowermost disc from the disc loaded cartridge is released. The individual disc dispenser further has a hollow well through which the released sensitivity disc is dispensed to the receiver.
According to a further embodiment, the individual disc dispenser further has a second surface for receiving and linearly sliding a disc loaded cartridge towards the first
surface.
According to an embodiment as illustrated in FIGURE 2, the disc dispensing apparatus (200) comprises a top portion (210) and a peripheral side wall (220). The top portion (210) and the peripheral side wall (220) are coupled to one another.
According to a further embodiment, the top portion and the peripheral side wall can be moulded inseperably to one another.
According to another embodiment, the peripheral side wall (220) of the disc dispensing apparatus (200) can be cylindrical in shape. However, those skilled in the art will appreciate that the shape of the peripheral side wall can be such that it facilitates the placement of the disc dispensing apparatus on top of the receiver during the disc dispensing process. The peripheral side wall can have a height upto about 30 mm. The peripheral side wall (220) allows the disc dispensing apparatus to rest on the receiver (not shown in the figure) or on the table top (not shown in the figure) or on a base station (not shown in the figure) during dispensing. It ensures that the disc dispensing apparatus remains steady during the disc dispensing operation.
According to another embodiment, the top portion (210) of the disc dispensing apparatus can be circular in shape and has a diameter of about 120 mm. However, those skilled in the art will appreciate that the shape of the disc dispensing apparatus comprising the top portion and the peripheral side wall can be such that it can be

placed on top of the receiver or on the table top or on a base station during the disc dispensing operation.
The top portion (210) comprises a plurality of individual disc dispensers (230) embedded within the top portion (210) of the disc dispensing apparatus.
As shown in FIGURE 2, each of the individual disc dispenser (230) has a first surface (240) which is enabled to release at least one disc from the disc loaded cartridge (not shown in the figure). The individual disc dispenser (230) can also further have a second surface (250) for receiving and linearly sliding a disc-loaded cartridge. The disc-loaded cartridge is slid from the second surface (250) to reach the first surface (240). On hitting the first surface (240), at least one disc from the disc loaded cartridge is released. The individual disc dispenser (230) is further provided with a hollow well (260). The released sensitivity disc is dispensed through the hollow well (260) on the receiver.
According to a further embodiment, the hollow well (260) of the individual disc dispenser can be used for dispensing sensitivity discs by tweezers.
According to an embodiment, the first surface (240) of the individual disc dispenser (230) is in a continuous arrangement with the hollow well (260) of the individual disc dispenser (230). However, the first surface (240) is positioned at a slightly higher level from the hollow well (260) to facilitate the release of at least one sensitivity disc from the disc loaded cartridge. The second surface (250) of the individual disc dispenser (230) is also in a continuous arrangement with the hollow well (260).
According to a further embodiment, a plurality of disc loaded cartridges can be slid simultaneously to the first surfaces (240) of a plurality of individual disc dispensers (230) to dispense several sensitivity discs simultaneously on the receiver during dispensing.

According to an embodiment, the individual disc dispensers (230) are positioned at a plurality of predetermined locations (280) on the top portion (210) of the disc dispensing apparatus (200). Such positioning of the individual disc dispensers (230) allows the sensitivity discs to be dispensed at a pre-defined distance from each other on the receiver.
According to another embodiment, the individual disc dispensers (230) are positioned in such a manner on the top portion (210) of the disc dispensing apparatus (200) that it facilitates sliding in a particular direction (270) of one or more disc loaded cartridges on the first surface (240) of at least one individual disc dispenser (230) during the dispensing operation. However those skilled in the art will appreciate that it is possible to design the plurality of individual disc dispensers (230) in an angular pattern on the top portion (210) of the disc dispensing apparatus (200) thereby providing one or more disc loaded cartridges to slide in multiple directions during the dispensing operation.
According to a further embodiment, the disc dispensing apparatus (200) is fabricated from a polymeric or a plastic material such as polystyrene. The disc dispensing apparatus can also be made of metal such as aluminium. However, those skilled in the art will appreciate that it is possible to manufacture the disc dispensing apparatus by using any material that can be moulded or machined without departing from the scope of the invention,
According to a further embodiment, the receiver is a growth medium carrier. The growth medium carrier can be a petri plate or any cell culture dish.
According a still further embodiment, the sensitivity discs are dispensed from the disc dispensing apparatus to a flat surface (not shown) in the receiver. The flat surface can be a growth medium such as nutrient broth or an agar gel.

According to another embodiment as shown in FIGURE 3, the plurality of individual disc dispensers (230) are arranged in a concentric pattern (310) forming at least one ring, on the top portion (210) of the disc dispensing apparatus (200). Preferably, the individual disc dispensers are arranged in a concentric pattern forming two rings on the top portion (210) of the disc dispensing apparatus (200), The concentric arrangement of the individual disc dispensers facilitates the sensitivity discs to be dispensed in a concentric pattern on the flat surface of the receiver, with a pre-defined distance between the dispensed discs. It further ensures uniform sensitivity zone diameters. This provision aids in improving the accuracy of analysis during antimicrobial susceptibility assays by entirely eliminating or minimizing overlap in the antimicrobial zones.
According to an embodiment, the top portion (210) further comprises a plurality of locking extensions (330) which extend to the lower surface of the top portion (210). The locking extensions (330) allow steady placement of the disc dispensing apparatus on the receiver such as a Petri dish.
According to yet another embodiment, FIGURE 4 shows the lower surface (410) of the disc dispensing apparatus (200). The lower surface (410) of the disc dispensing apparatus (200) has a plurality of locking extensions (330) for engaging the disc dispensing apparatus with a receiver. The lower surface (410) further has a plurality of distensions (340) towards the edges of the peripheral side wall (220). The distensions (340) provide for the coupling of the disc dispensing apparatus with an optional base station (not shown) during the dispensing process.
According to a further embodiment as shown in FIGURE 5, the disc dispensing apparatus (200) optionally comprises a base station (500). The base station (500) is enabled to position the receiver (not shown in the figure) onto to the base plate (510) of the base station (500). The base station (500) further has a flat surface (530) to

securely hold a petri dish (not shown in the figure) having a diameter of about 90 mm. during the dispensing process. The base station further has a plurality of protruberances (540) to hold a receiver such as a petri dish having a diameter of about 100 mm during the disc dispensing operation. The base station further includes at least one locking groove (520) to facilitate the disc dispensing apparatus (200) to be coupled to the base station (500) during the dispensing process. The base station 500 further optionally has a plurality of receptacles (560) for holding the disc loaded cartridges to be used for dispensing. The base station (500) ensures that the alignment between receiver and the disc dispensing apparatus is not disturbed during the dispensing process. The base station further ensures alignment of the receiver during change of cartridges between different dispenses. The height of base station can be changed to allow dispensing of the discs in a pathogen free zone such as in proximity of flame near Bunsen burner.
According to yet another embodiment, FIGURE 6 shows a disc dispensing apparatus (200) coupled to the base station (500) wherein the receiver (620) is kept on the base plate (510) of the base station (500) to ensure alignment between the receiver (620) and the disc dispensing apparatus (200) at the time of dispensing. Several disc-loaded cartridges (610) to be used for dispensing are placed in the plurality of receptacles (560) provided on the base station (500).
According to a further embodiment, the invention relates to a method of linearly dispensing at least one sensitivity disc from a disc dispensing apparatus to a flat surface in a receiver such as a Petri dish. The method involves receiving at least one disc-loaded cartridge on at least one individual disc dispenser located on a top portion of the disc dispensing apparatus. The disc-loaded cartridge is moved against a first surface of the individual disc dispenser to release at least one sensitivity disc from the disc loaded cartridge. The released sensitivity disc is dispensed through a hollow well of the disc dispenser on to the surface of the receiver.

According to a further embodiment, the receiving step involves receiving at least one disc loaded cartridge on a second surface of at least one individual disc dispenser. The disc loaded cartridge is then slid from the second surface to reach the first surface of the individual disc dispenser.
According to a preferred embodiment, the method comprises receiving a disc loaded cartridge on a second surface (250) of at least one individual disc dispenser (230) located on a top portion (210) of the disc dispensing apparatus (200).
The disc loaded cartridge is then linearly slid from the second surface (250) towards the first surface (240) of the individual disc dispenser (230) located on the top portion (210) of the disc dispensing apparatus (200). Once the cartridge reaches and hits the first surface (240) at least one sensitivity disc from the disc loaded cartridge is released. The released sensitivity disc is further dispensed on a receiver through a hollow well (260) located on the individual disc dispenser (230). The hollow well (260) which is in a continuous arrangement with the first surface (240) allows dispensing of the sensitivity disc at a pre-defined position on the receiver. However, the first surface (240) is positioned at a slightly higher level from the well to facilitate the release of the sensitivity disc. The second surface (250) of the individual disc dispenser (230) is also in a continuous arrangement with the hollow well (260).
According to a still further embodiment, the invention relates to a method of simultaneously dispensing a plurality of sensitivity discs from the disc dispensing apparatus on the receiver.
According to yet another embodiment, the invention relates to a use of the disc dispensing apparatus, in dispensing one or more sensitivity discs to a receiver such as

a Petri dish during antimicrobial susceptibility assays such as antibiotic sensitivity testing to drugs such as erythromycin, gentmycin etc.
The disc dispensing apparatus of the invention is simple and inexpensive to manufacture. It allows for reproducible distances between the dispensed sensitivity discs. The concentric pattern of the individual disc dispensers of the disc dispensing apparatus allow the discs to be dispensed at uniform distances from each other thereby ensuring a uniform sensitivity zone diameter between the discs. This further helps in improving the accuracy of the sensitivity test results. It also helps in reducing costs due to maximum utilization of the petri dish area. Further, if a disc is stuck in one of the disc-loaded cartridge, the simplicity of the device allows for easy detection and correction of such a malfunction occurring during dispensing.
As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which can be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure.

CLAIMS We claim:
1. A disc dispensing apparatus for linearly dispensing at least one sensitivity
disc, the disc dispensing apparatus comprising:
a top portion, wherein the top portion comprises a plurality of individual disc dispensers embedded in the top portion and wherein each individual disc dispenser comprises a first surface for releasing at least one sensitivity disc from a disc-loaded cartridge and a hollow well for dispensing the sensitivity disc at a pre-defined position on a receiver; and,
a peripheral side wall to position the disc dispensing apparatus on the receiver, wherein the peripheral side wall is coupled to the top portion.
2. The disc dispensing apparatus of claim 1, wherein the individual disc dispenser further comprises a second surface for receiving and linearly sliding the disc-loaded cartridge.
3. The disc dispensing apparatus of claim 1, wherein the plurality of the individual disc dispensers is positioned at a plurality of pre-determined locations on the top portion of the disc dispensing apparatus to dispense a plurality of sensitivity discs at a pre-defined and reproducible distance from each other on the receiver.
4. The disc dispensing apparatus of claim I, wherein the top portion is circular and has a diameter of about 120 mm.
5. The disc dispensing apparatus of claim 1, wherein the peripheral side wall has a height upto about 30 mm.

6. The disc dispensing apparatus of claim 1, wherein the disc dispensing apparatus is made of a polymeric material or metal.
7. The disc dispensing apparatus of claim 1, wherein the receiver comprises a growth medium carrier.
8. The disc dispensing apparatus of claim 1, wherein the plurality of the individual disc dispensers are in a concentric pattern comprising at least one ring on the top portion of the disc dispensing apparatus to dispense the sensitivity discs in a concentric pattern on the receiver.
9. The disc dispensing apparatus of claim 1, further comprising locking extensions to align the disc dispensing apparatus and the receiver to each other during dispensing.
10. The disc dispensing apparatus of claim 1, further optionally comprising a base station wherein the base station is enabled to position and align the receiver with the disc dispensing apparatus during dispensing.
11. A method of linearly dispensing a sensitivity disc from a disc dispensing apparatus to a receiver, the method comprising steps of:
a. receiving at least one disc-loaded cartridge on at least one individual
disc dispenser located on a top portion of the disc dispensing
apparatus;
b. moving the disc loaded cartridge against a first surface of the
individual disc dispenser to release at least one sensitivity disc from
the disc-loaded cartridge; and,

c. dispensing the released sensitivity disc to the receiver through a hollow well of at least one disc dispenser on the receiver.
12. The method of claim 11, wherein the receiving step further comprises receiving a disc-loaded cartridge on a second surface of the individual disc dispenser.
13. The method of claim 11, wherein the receiving step further comprises sliding the disc-loaded cartridge from the second surface to reach the first surface of the individual disc dispenser.
14. A use of a disc dispensing apparatus, disc dispensing apparatus comprising:
a top portion, wherein the top portion comprises a plurality of individual disc dispensers embedded in the top portion and wherein each individual disc dispenser comprises a first surface for releasing at least one sensitivity disc from a disc-loaded cartridge and a hollow well for dispensing the sensitivity disc at a pre-defined position on the receiver; and, a peripheral side wall coupled to the top portion to position the disc dispensing apparatus on the receiver, wherein the peripheral side wall is moulded to the top portion; in linearly dispensing at least one sensitivity disc to a receiver during antimicrobial sensitivity assays.
15. A disc dispensing apparatus for dispensing at least one sensitivity disc to a
receiver substantially as herein described with reference to the accompanying
drawings.