DESC:FIELD OF THE INVENTION:
The present invention relates to a point of care (POC) diagnostic device for plasma separation and electrolyte detection in clinical laboratory investigation. The invention combines passive membrane separation and microfluidic technology with integrated Electrochemical sensors for sodium, potassium, calcium, urea creatine and lactate detection other electrolytes, biochemistry parameters. The invention offers rapid, accurate and portable blood analysis for clinical and resource-limited settings. This device has the potential to improve the clinical management of electrolyte imbalance, chronic kidney disease and cardiovascular disease particularly in rural areas where access to laboratory testing may be limited.
BACKGROUND OF THE INVENTION:
The electrolyte imbalances are critical indicators for various health conditions, such as sepsis, trauma and ventilator weaning. Current laboratory methods for measuring electrolytes are time-consuming, costly and inaccessible in resource-limited settings. The existing technology for testing and blood component separation require high volume of blood samples and such laboratories that perform such testing may not be available or have reach to undeserved areas. The Current standard requires use of laboratory centrifugation instrument, which is bulky and entails specially trained personnel. Further these laboratories provide highly costly and not that portable testing option. Peoples prefer easy to handle that is portable and cost-effective tool. Significant advances have been made in the development of portable, compact, and low-cost detection technologies, bringing immunoassay and nucleic acid-based testing from centralized laboratories to point of care settings.
However, sample preparation steps such as rapid separation of plasma from whole blood is still a challenge. In view of such limitations and drawbacks of existing laboratories technologies there is a pressing need for a portable, affordable, and accurate point-of care device that is capable of rapid plasma separation as well as electrolyte measurement is a single device. Many researchers and inventors have worked on it and developed some related works but they are lacking in design and missing some features. Some of such inventions are discussed below.
Reference has been made to CN104107059B titled “Biological fluid collection device and test system” which uses a device that collected blood and after biological fluid collection, device transferred to point of care device. The disclosure provides a kind of biological fluid collection device, and such as blood collection device, it is suitable to receiving blood sample, blood sample has cellular portions and blood plasma fractions. The collected blood sample after product, blood sample can be transferred to point-of care test device or life by biological fluid collection device, Logistics body separates and test device, such as blood separation and test device. Displaced blood sample After product, biofluid separates and tests device energy separated plasma part and cellular portions and divides, Analysis blood sample also obtains test result.
Another reference has been made to US3322114A titled “APPARATUS FOR SECURING A SAMPLE OF BLOOD PLASMA FOR TESTING” Joseph Portnoy and George S. Warner, Baltimore, Md., the invention resides primarily in a hypodermic needle of a suitable diameter and length for extracting blood from a person or animal secured to the neck of a bottle or container of a suitable transparent or at least translucent plastic such as polyethylene, said bottle containing an anticoagulant such as heparin or one of the salts of ethylenediaminetetraacetic acid and a lectin or phytoagglutinin material.
Another reference has been made to US10105083B1 titled “Microscale plasma separator” The invention is used methods and devices for rapid fractionation of cells and plasma from small amounts of blood, obtainable from simple finger-prick blood-drawing techniques, or a blood collection container. The inventions are used for viral load testing, such as for HIV viral load testing in resource-limited settings. The devices are used for standard laboratory tests such as electrolyte, lipid, protein and viral RNA analysis that require the use of plasma.
Another reference has been made to US2021231643A1, titled “VACUUM-ASSISTED PLASMA SEPARATION”, by SIEMENS HEALTHCARE DIAGNOSTICS INC, dated 2014-08-01, which relates to a plasma separation system and process for providing filtered plasma from a blood sample is described. The system may include a blood separation well having a separation membrane for filtering the blood sample. The filtering process may be aided by the use of a negative or positive pressure source attached to the plasma separation system.
Another reference has been made to CN109351384A, titled “Blood test collection device”, by DALIAN HUIHANG TECH DEVELOPMENT CO LTD, dated 2018-11-14, which relates to a blood test collection device. The blood test collection device includes a blood collection device body and blood collection tubes, an outer-layer support plate is disposed on the outer side of the blood collection device body, an inner-layer support plate is disposed in the outer-layer support plate, and splints are disposed in the blood collection device body and divides the blood collection device body into a plurality of grooves; a portable handle is arranged on one side of the blood collection device body, an antiskid plate is disposed on the side same as the portable handle, and the blood collection tubes are disposed in the grooves; common serum tube red head covers are disposed on the left sides of the blood collection tubes, a quick serum tube orange redhead cover is disposed on one side of the right end of each common serum tube red head cover, an inert separation gel coagulation-promoting tube golden head cover is disposed on one side of the right end of each quick serum tube orange red head cover. The head covers are different in color and length, can be selected for use according to specific demands and are separated from one another. The blood test collection device is simple in structure and convenient to use and carry.
Another reference has been made to US2017191982A1, titled “Constriction-Expansion Blood Plasma Separation”, by MASSACHUSETTS INST TECHNOLOGY, dated 2016-01-06, which relates to a portable, microfluidic blood plasma separation device is presented featuring a constriction-expansion design, which can produce up to about 100% purity for undiluted blood at least about 9% yield. This level of purity represents an improvement of at least one order of magnitude with increased yield compared to that achieved previously using passive separation. The system features high flow rates, 5-30 µL/min plasma collection, with minimal clogging and biofouling. The simple, portable blood plasma separation design can be hand-driven and can easily be incorporated with microfluidic or laboratory scale diagnostic assays. The separation system can be used in conjunction with portable analyte detection tests at concentrations well below clinical relevancy for undiluted whole blood.
Another reference has been made to US12117435B2, titled “Portable electrochemical-sensor system for analysing user health conditions and method thereof”, by CARDIAI TECH LTD, dated 2019-11-04, which relates to an electrochemical-sensor structure having a substrate and a nanostructured-sensing surface that receives a volume of a sample fluid. A sample region of the electrochemical-sensor structure for receiving the sample fluid volume is sized such that the volume of the fluid is sufficient to operatively cover a portion of the sample region of the electrochemical-sensor structure including the nanostructured-sensing surface. The electrochemical-sensor structure is connectable to a portable point-of-care (PoC) device. The PoC device may detect the energy properties of the sample fluid from the sample region of the electrochemical-sensor structure, to produce a signal comprising a fluid reading wherein the fluid reading is related to the energy properties of a biomarker in the sample fluid thereby indicating the presence, the absence, or the quantity of the biomarker in the sample fluid.
However, none of the above-discussed inventions relates to a point-of-care (POC) device for plasma separation and electrolyte detection that provides a portable and affordable method for rapid plasma separation as well as electrolyte measurement in a single device. The present invention combines passive membrane separation technology and microfluidic technology with the integrated potentiometric sensors for sodium, potassium, calcium, urea, creatinine, lactate detection, etc. Further, the invention integrates components including a membrane separation layer for efficient plasma separation from whole blood, a microfluidic channel system for guiding plasma towards the sensor zone via capillary action, and screen-printed ion-selective electrodes (ISE) for real-time measurement of electrolytes. Additionally, the invention minimizes sample volume requirements up to 100 µL and ensures electrolytes detection even with lower concentrations (<1 mM). The invention comprises a portable, credit card-sized design and provides real-time electrolyte measurement with rapid response times within 2-3 minutes.
OBJECTIVE OF THE INVENTION:
The main objective of the present invention is to provide a point of care (POC) device for plasma separation and electrolyte detection.
Another objective of the invention is to combine passive membrane separation technology and microfluidic technology with the integrated potentiometric sensor or ion-selective electrodes (ISEs) for sodium, potassium, calcium, urea, creatinine as well as lactate detection.
Another objective of the invention to provide a portable credit card sized POC device for plasma separation and real time electrolyte measurement within rapid response time between 2- 5 minutes.
Another objective of the invention is to provide a membrane separation layer that performs selective plasma filtration while retaining blood cells and ensures efficient separation of plasma from whole blood introduced into the device, enabling downstream analysis in the microfluidic system.
Another objective of the invention is to a microfluidic system with hydrophilic coating to facilitate efficient plasma movement via capillary action or slight vacuum pressure.
Another objective of the invention is to minimize sample volume requirements.
Another objective of the invention is to incorporate screen-printed ion-selective electrodes and reference electrodes for real time measurement of multiple analytes.
Another objective of the invention is to provide fabrication method for fabricating ion-selective electrodes including sodium ion-selective electrode, Potassium ion-selective electrodes and reference electrode using screen-printed technology and drop-cast methodologies.
Another objective of the invention is to improve the clinical management of electrolyte imbalance, particularly in underserved areas where access to laboratory testing may be limited.
SUMMARY OF THE INVENTION:
The present invention provides a point-of-care (POC) device for plasma separation and electrolyte detection. The invention combines passive membrane separation and microfluidic technology with the integrated ion-selective electrodes (ISEs) for real time measurement of electrolytes. The passive membrane of the diagnostic device comprises pore sizes between 2 to 6 microns. The membrane separation layer performs selective plasma filtration while retaining blood cells by utilizing passive filtration technology and direct separated plasma towards the microfluidic channel. The microfluidic channel is equipped with a hydrophilic coating to facilitate efficient plasma movement towards the senso zone. Further, the microfluidic channel design of the invention minimized blood sample volume requirements. The sensing zone of the invention incorporates screen-printed reference electrode and ion-selective electrodes (ISEs) for multiple analytes including sodium, potassium, calcium, urea, creatinine, etc. The sensing zone also include screen-printed reference electrodes as well as ion-selective electrodes, and ion-selective membrane with specific ionophores or enzymatic coatings. The invention can detect analyte with lower concentration (<1mM) and provides rapid response times within 2 to 5 minutes. The said membrane separation layer is comprising of polymers such as polycarbonate, polyethersulfone or cellulose acetate etc. The invention is a disposable cassette consisting of an inlet channel and outlet channel where a few microliters of blood are dropped into the inlet channel containing a filtration membrane where the plasma is separated from the blood using passive filtration technology. The device provides fast, reliable, affordable and portable testing for the detection of sodium and potassium levels in plasma, and making it an essential tool for the clinical management of electrolyte imbalances.
STATEMENT OF THE INVENTION:
Accordingly, the present invention provides a point-of-care (POC) device for plasma separation and electrolyte detection in real time by combining passive membrane separation and microfluidic technology with integrated ion selective electrodes for real time measurement of electrolytes including sodium, potassium, calcium, urea, creatinine and lactate detection; the present invention is a disposable cassette and integrates three key components including a membrane separation layer, a microfluidic channel system, and a sensing zone with ion-selective electrodes; the microfluidic channel design of the invention minimizes blood sample volume requirements and facilitate plasma movement towards sensing zone via capillary action or slight vacuum pressure for precise measurement; Further, the integration of microfluidic system with sensing zone ensure efficient plasma-electrode interaction for real time measurement of electrolytes; the integrated ion-selective with specific ionophores or enzymatic coatings of the sensing zone can detect electrolytes even with low concentration below 1mM (for sodium and potassium) and results are showed within 2-5 minutes of the process.
BRIEF DESCRIPTION OF THE DRAWINGS:
Figure 1: shows middle layer of the present invention that includes a membrane separation layer 101, a microfluidic channel system 102, and a sensing zone 103. The said membrane separation layer 101 comprises a polymer layer 104 which is constructed from polycarbonate, polyethersulfone or cellulose acetate etc.
Figure 2: shows top layer of the present invention that includes inlet 201 of the device, and polymer layer 104.
Figure 3: shows bottom layer of the present invention that includes sensing electrodes 301 and their connections 302.
The figures are merely for illustration purpose and shall not be construed to limit the scope of the invention.
DETAILED DESCRIPTION OF THE INVENTION:
It should be noted that the particular description and embodiments set forth in the specification below are merely exemplary of the wide variety and arrangement of instructions which can be employed with the present invention. The present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. All the features disclosed in this specification may be replaced by similar other or alternative features performing similar or same or equivalent purposes. Thus, unless expressly stated otherwise, they all are within the scope of present invention. Various modifications or substitutions are also possible without departing from the scope or spirit of the present invention. Therefore, it is to be understood that this specification has been described by way of the most preferred embodiments and for the purposes of illustration and not limitation.
Whole blood micro sampling provides many benefits, such as remote, patient-centric, and minimally invasive sampling. However, blood plasma and not whole blood, is the prevailing matrix in clinical laboratory investigations. There are many diseases, such as hypertension, high blood pressure, cardiovascular disease, kidney disease, and renal tubular acidosis, for which the concentration of electrolytes such as sodium and potassium is important. Although traditional methods are sensitive and selective, expensive laboratory-based equipment is necessary to quantify potassium and sodium analyses in complex biological samples. Since point-of-care (POC) monitoring of biomarkers can improve clinical outcome. There is growing demand to develop electrolyte detection systems that use miniaturised portable devices for medical diagnosis.
The present invention provides a point of care (POC) device for plasma separation and electrolyte detection that separates blood plasma from the whole blood to diagnose hypertension or cardiovascular diseases cystic fibrosis, kidney disease, acute kidney injury, renal tubular acidosis, and/or adrenal gland problems. The present invention for plasma separation and electrolyte detection is an important advancement in healthcare. The device combines the use of microfluidic technology, electrochemical sensors including potentiometric ISE with solid state configuration using screen-printed electrode 301. The device will provide fast, affordable and portable testing for the clinical management of electrolyte imbalance, ventilator weaning, sepsis management and trauma care, etc.
The present invention provides a point-of-care (POC) device for plasma separation and electrolyte detection that combines passive membrane separation technology 101 and microfluidic technology 102 with integrated potentiometric sensors for sodium, potassium, calcium, urea, creatinine and lactate detection. The device also integrates ion-selective electrodes (ISEs) 301 for real time measurements of multiple analytes. The device integrates three key components; a membrane separation layer 101, a microfluidic channel system 102 and a sensing zone 103 with ion-selective electrodes (ISE) 301. The said device consists of three layers that is top layer, middle layer and bottom layer. Said top layer comprises inlet 201, middle layer comprises a membrane filter 101, a microfluidic channel 102 and a sensing zone 103, where bottom layer comprises sensing electrodes 301 and their connections 302.
The present invention utilizes a passive membrane separation layer 101 that performs selective plasma filtration while retaining blood cells. The membrane separation layer 101 is constructed from polymers 104, such as polycarbonate, polyethersulfone or cellulose acetate. The pore sizes of this membrane separation layer 101 is ranges from 2 to 6 microns for efficient plasma separation from whole blood, and thickness ranges from 50 to 200 microns that ensures durability and optimal fluid dynamics. This layer efficiently separates plasma from whole blood introduced into the device, enabling downstream analysis in the microfluidic system.
The present invention utilizes microfluidic system that ensures controlled plasma flow to the sensing zone 103. The microfluidic system includes channel 102 widths of 100-500 microns, heights ranging from 50 to 200 microns and lengths of 1-10 nm. These dimensions of the microfluidic channel 102 are tailored to the device footprint. This microfluidic channel 102 is designed with a hydrophilic coating that facilitates efficient plasma movement towards sensing zone 103 via capillary action or slight vacuum pressure. The design minimizes sample volume requirements and supports consistent flow to the sensing zone 103 for precise measurements.
The sensing zone 103 is the analytic core of the device, incorporating screen-printed ion-selective electrodes (ISEs) 301 for multiple analytes. The sensing zone 103 incorporates screen-printed Ag or AgCl reference electrodes 301 and ion-selective electrodes 301 for sodium, potassium, calcium, urea, creatinine, and lactate. The sensing zone 103 also includes custom membranes 101 which are fabricated with specific ionophores or enzymatic coatings to ensure selectivity. The sensing zone designed for low detection limits (<1 mM for sodium and potassium) with rapid response times (2-5 minutes). The sensing zone’s 103 integration into the microfluidic system ensures efficient plasma-electrode 301 interaction for real-time analysis.
The microfluidic channel 102 of the invention is integrated with membrane separation layer 101 and sensing zone 103 with ion-selective electrodes (ISE) 301. The incorporation of microfluidic channels 102 guides plasma movement towards the sensing zone 103 and the integrated ion-selective electrodes 301 detects and measure electrolytes including sodium, potassium, calcium, urea, creatinine and lactate detection in real time. The microfluidic channel design 102 of the invention minimizes sample volume requirements and thus it requires only 100 microliters of blood volume for plasma separation and electrolyte measurement. The integration of sensing zone 103 into the microfluidic channel 102 ensures efficient plasma-electrode 301 interaction for real time analysis.
The present invention measures electrolytes using finger prick or venous blood utilizing microfluidics passive separation technology. It is a disposable cassette consisting of an inlet 201, channel 102, and outlet. where a few microliters of blood are dropped into the inlet 201 channel containing a filtration membrane 101 where the plasma is separated from the blood using passive filtration technology. Through microchannels 102, the separated plasma reaches a modified screen-printed electrode 301 containing a selective membrane 101 for sodium and potassium, reference, and counter electrode 301. The modified printed electrolytes are inserted into a handheld device.
The present invention is portable, and its design is like credit card size. The design of the device includes an inlet 201 through which the blood sample is introduced into the device, and thereafter the membrane separation layer 101 performs selective plasma filtration while retaining blood cells using passive filtration technology. This membrane separation layer 101 ensures efficient blood-plasma separation, enabling downstream analysis in the microfluidic system 102. Through microchannels 102, the separated plasma reaches the modified screen-printed electrode 301 containing an ion-selective membrane 101 with specific ionophores or enzyme coating for sodium and potassium, etc. These modified printed electrodes 301 are further inserted into the bottom layer 107 of the device through connections 302 using the screen-printed method and drop-casting method.
The electrochemical ion-selective electrodes (ISE) 301 sensor is fabricated by following steps:
a) fabrication of sodium ion-selective electrode (Na+ ISE) 301:
? Firstly, PEDOT: PSS (18%) with ethylene glycol (6%), and sonicate mixture for about 30 minutes;
? Drop cast of prepared solution onto a screen-printed electrode (SPE) 301, and dry at 80°C for 30 minutes;
? Then, mix of sodium ionophore (2%), KTFPB (0.55%), THF, PVC (33%) and 62 µL NPOE (65.45%) via vortex stirring; and
? Drop cast the prepared mixture onto coated screen-printed electrode (SPE) 301.
b) fabrication of Potassium Ion-selective Electrode (K+ ISE) 301:
? combine potassium ionophore (2%), KTFPB (0.5%), THF, PVC (33%), and NPOE (65.45%); and
? Then, stir the above mixture until it becomes homogenous solution;
? Drop cast the volume of solution onto the surface of screen-printed electrode (SPE) 301.
c) fabrication of reference electrode 301:
? Dissolve NaCl in 1 mL methanol, and stir for 10 minutes;
? Then, add polyvinyl butyral, and stir the mixture again for 15 minutes; and
? Drop-cast final mixture onto the Ag/AgCl reference electrode 301.
The present invention provides working mechanism which are as follows:
? 100 µL of whole blood is introduced into the device;
? Then, the membrane layer 101 separates plasma, which flows into the microfluidic channels 102;
? After that plasma reaches the sensing zone 103, where ion-selective electrodes 301 measure analyte concentrations;
? Results are displayed within 2-5 minutes on screen of the device.
Referring to figure 1, that represents middle layer of the present invention that includes a membrane separation layer 101, a microfluidic channel system 102, and a sensing zone 103. The said membrane separation layer 101 comprises a polymer layer 104 which is constructed from polycarbonate, polyethersulfone or cellulose acetate etc. The membrane separation layer 101 performs selective plasma filtration while retaining blood cells. This layer efficiently separates plasma from whole blood introduced into the device, enabling downstream analysis in the microfluidic system. Said membrane filter 101 is connected with sensing zone 103 through the channel 102 for guiding plasma to detection zones.
Referring to figure 2, that represents top layer of the present invention that includes inlet 201 of the device, and polymer layer 104. Through the inlet 201, the blood is introduced into the device. The polymer layer 104 is constructed from polycarbonate, polyethersulfone or cellulose acetate etc. Where, figure 3 represents the bottom layer of the present invention that includes sensing electrodes 301 and their connections 302. The screen-printed sensing electrodes 301 are connected on the bottom layer 302 of the device.
So, accordingly, the present invention provides a point-of care (POC) device for plasma separation and electrolyte detection by utilizing A membrane layer 101 for plasma separation with pore sizes of 2-6 microns and thickness of 50-200 microns, constructed from polycarbonate, polyethersulfone, or cellulose acetate. A microfluidic system with dimensions of 100-500 microns (width), 50-200 microns (height), and 1-10 mm (length), featuring a hydrophilic coating for plasma flow. Integrated ion-selective electrodes 301 with specific ionophores or enzymatic coatings for detecting sodium, potassium, calcium, urea, creatinine, and lactate. Fabrication protocols for ion-selective and reference electrodes 301 using screen-printed technology and drop-cast methodologies. A point-of-care device requiring only 100 µL of whole blood, delivering analyte results in 2-5 minutes with a portable, credit card-sized design. Utility in clinical diagnostics, particularly in monitoring electrolyte imbalances, ventilator weaning, sepsis management, and trauma care. The invention represents a significant advancement in portable diagnostic technology, offering rapid, low-cost, and reliable analysis in various healthcare settings.
In an exemplary embodiment, said a point-of care (POC) device for plasma separation and electrolyte detection comprising of: three layers that is top layer, middle layer and bottom layer; said top layer comprises inlet 201, middle layer comprises a membrane filter 101, a microfluidic channel 102 and a sensing zone 103, where bottom layer comprises sensing electrodes 301 and their connections 302; said device combines passive membrane separation technology 101 and microfluidic technology 102 with integrated potentiometric sensors for sodium, potassium, calcium, urea, creatinine and lactate detection; said device also integrates ion-selective electrodes (ISEs) 301 for real time measurements of multiple analytes; said membrane separation layer 101 is constructed from polymers 104, and it is connected with sensing zone 103 through the channel 102 for guiding plasma to detection zones; said sensing zone 103 is integrated into the microfluidic system to ensure efficient plasma-electrode 301 interaction for real-time analysis.
In another embodiment, said passive membrane separation layer 101 that performs selective plasma filtration while retaining blood cells, and said layer is constructed from polymers 104, such as polycarbonate, polyethersulfone or cellulose acetate with pore sizes of 2 to 6 microns for efficient plasma separation from whole blood, and thickness ranges from 50 to 200 microns that ensures durability and optimal fluid dynamics; further, this layer efficiently separates plasma from whole blood introduced into the device, enabling downstream analysis in the microfluidic system.
In another embodiment, said said microfluidic system that ensures controlled plasma flow to the sensing zone 103, and it includes channel 102 widths of 100-500 microns, heights ranging from 50 to 200 microns and lengths of 1-10 nm, and this is tailored to the device footprint; further to this, it is designed with a hydrophilic coating that facilitates efficient plasma movement towards sensing zone 103 via capillary action or slight vacuum pressure, and the design minimizes sample volume requirements and supports consistent flow to the sensing zone 103 for precise measurements.
In another embodiment, said microfluidic channel 102 is integrated with membrane separation layer 101 and sensing zone 103 with ion-selective electrodes (ISE) 301 guides plasma movement towards the sensing zone 103 and the integrated ion-selective electrodes 301 detects and measure electrolytes including sodium, potassium, calcium, urea, creatinine and lactate detection in real time; said microfluidic channel design 102 minimizes sample volume requirements and thus it requires only 100 microliters of blood volume for plasma separation and electrolyte measurement.
In another embodiment, said sensing zone 103 is the analytic core of the device, incorporating screen-printed ion-selective electrodes (ISEs) 301 for multiple analytes, and it also incorporates screen-printed Ag or AgCl reference electrodes 301 and ion-selective electrodes 301 for sodium, potassium, calcium, urea, creatinine, and lactate; further, it includes custom membranes 101 which are fabricated with specific ionophores or enzymatic coatings to ensure selectivity, and the sensing zone 103 designed for low detection limits that is <1 mM for sodium and potassium with rapid response times of 2-5 minutes.
In another embodiment, said device measures electrolytes using finger prick or venous blood utilizing microfluidics passive separation technology, and it is a disposable cassette consisting of an inlet 201, channel 102, and outlet, where a few microliters of blood are dropped into the inlet 201 channel containing a filtration membrane 101 where the plasma is separated from the blood using passive filtration technology; through microchannels 102, the separated plasma reaches a modified screen-printed electrode 301 containing a selective membrane 101 for sodium and potassium, reference, and counter electrode 301, and the modified printed electrolytes are inserted into a handheld device.
In another embodiment, said electrochemical ion-selective electrodes (ISE) 301 sensor is fabricated by following steps:
a) fabrication of sodium ion-selective electrode (Na+ ISE) 301:
? Firstly, Mix PEDOT: PSS (18%) with ethylene glycol (6%), and sonicate mixture for about 30 minutes;
? Drop cast the prepared solution onto a screen-printed electrode (SPE) 301, and dry at 80°C for 30 minutes;
? Then, mix sodium ionophore (2%), KTFPB (0.55%), THF, PVC (33%) and NPOE (65.45%) via vortex stirring; and
? Drop cast of prepared mixture onto coated screen-printed electrode (SPE) 301;
b) fabrication of Potassium Ion-selective Electrode (K+ ISE) 301:
? Combine potassium ionophore (2%), KTFPB (0.5%), THF, PVC (33%), and NPOE (65.45%); and
? Then, stir the above mixture until it becomes homogenous solution;
? Drop cast the volume of solution onto the surface of screen-printed electrode (SPE) 301;
c) fabrication of reference electrode 301:
? Dissolve 50 mg NaCl in 1 mL methanol, and stir for 10 minutes;
? Then, add 79.1 mg polyvinyl butyral, and stir the mixture again for 15 minutes; and
? Drop-cast 3 µL volume of final mixture onto the Ag/AgCl reference electrode 301.
In another embodiment, said working mechanism of the device comprising steps of:
a) 100 µL of whole blood is introduced into the device;
b) Then, the membrane layer 101 separates plasma, which flows into the microfluidic channels 102;
c) After that plasma reaches the sensing zone 103, where ion-selective electrodes 301 measure analyte concentrations;
d) Results are displayed within 2-5 minutes on screen of the device.
While particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from this invention in its broader aspects and, therefore, the aim in the present invention is to cover all such changes and modifications as fall within the true spirit and scope of this invention.
ADVANTAGES OF THE INVENTION:
1. Easy to use, portable and cost-effective device
2. Provides fast, affordable and portable testing for the detection of sodium and potassium levels in plasma
3. Improve the clinical management of electrolyte imbalance in remote and underserved areas
4. Designed for low detection limits
5. real time electrolytes measurement
,CLAIMS:I CLAIM:
1. A point-of care (POC) device for plasma separation and electrolyte detection comprising of: three layers that is top layer, middle layer and bottom layer; said top layer comprises inlet 201, middle layer comprises a membrane filter 101, a microfluidic channel 102 and a sensing zone 103, where bottom layer comprises sensing electrodes 301 and their connections 302; said device combines passive membrane separation technology 101 and microfluidic technology 102 with integrated potentiometric sensors for sodium, potassium, calcium, urea, creatinine and lactate detection; said device also integrates ion-selective electrodes (ISEs) 301 for real time measurements of multiple analytes; said membrane separation layer 101 is constructed from polymers 104, and it is connected with sensing zone 103 through the channel 102 for guiding plasma to detection zones; said sensing zone 103 is integrated into the microfluidic system to ensure efficient plasma-electrode 301 interaction for real-time analysis.
2. The device as claimed in claim 1, wherein said passive membrane separation layer 101 that performs selective plasma filtration while retaining blood cells, and said layer is constructed from polymers 104, such as polycarbonate, polyethersulfone or cellulose acetate with pore sizes of 2 to 6 microns for efficient plasma separation from whole blood, and thickness ranges from 50 to 200 microns that ensures durability and optimal fluid dynamics; further, this layer efficiently separates plasma from whole blood introduced into the device, enabling downstream analysis in the microfluidic system.
3. The device as claimed in claim 1, wherein said microfluidic system that ensures controlled plasma flow to the sensing zone 103, and it includes channel 102 widths of 100-500 microns, heights ranging from 50 to 200 microns and lengths of 1-10 nm, and this is tailored to the device footprint; further to this, it is designed with a hydrophilic coating that facilitates efficient plasma movement towards sensing zone 103 via capillary action or slight vacuum pressure, and the design minimizes sample volume requirements and supports consistent flow to the sensing zone 103 for precise measurements.
4. The device as claimed in claim 1, wherein said microfluidic channel 102 is integrated with membrane separation layer 101 and sensing zone 103 with ion-selective electrodes (ISE) 301 guides plasma movement towards the sensing zone 103 and the integrated ion-selective electrodes 301 detects and measure electrolytes including sodium, potassium, calcium, urea, creatinine and lactate detection in real time; said microfluidic channel design 102 minimizes sample volume requirements and thus it requires only 100 microliters of blood volume for plasma separation and electrolyte measurement.
5. The device as claimed in claim 1, wherein said sensing zone 103 is the analytic core of the device, incorporating screen-printed ion-selective electrodes (ISEs) 301 for multiple analytes, and it also incorporates screen-printed Ag or AgCl reference electrodes 301 and ion-selective electrodes 301 for sodium, potassium, calcium, urea, creatinine, and lactate; further, it includes custom membranes 101 which are fabricated with specific ionophores or enzymatic coatings to ensure selectivity, and the sensing zone 103 designed for low detection limits that is <1 mM for sodium and potassium with rapid response times of 2-5 minutes.
6. The method as claimed in claim 1, wherein said device measures electrolytes using finger prick or venous blood utilizing microfluidics passive separation technology, and it is a disposable cassette consisting of an inlet 201, channel 102, and outlet, where a few microliters of blood are dropped into the inlet 201 channel containing a filtration membrane 101 where the plasma is separated from the blood using passive filtration technology; through microchannels 102, the separated plasma reaches a modified screen-printed electrode 301 containing a selective membrane 101 for sodium and potassium, reference, and counter electrode 301, and the modified printed electrolytes are inserted into a handheld device.
7. The method as claimed in claim 1, wherein said electrochemical ion-selective electrodes (ISE) 301 sensor is fabricated by following steps:
a) fabrication of sodium ion-selective electrode (Na+ ISE) 301:
? Firstly, PEDOT: PSS (18%) with ethylene glycol (6%), and sonicate mixture for about 30 minutes;
? Drop cast the prepared solution onto a screen-printed electrode (SPE) 301, and dry at 80°C for 30 minutes;
? Then, mix sodium ionophore (2%), KTFPB (0.55%), THF, PVC (33%) and NPOE (65.45%) via vortex stirring; and
? Drop cast prepared mixture onto coated screen-printed electrode (SPE) 301;
b) fabrication of Potassium Ion-selective Electrode (K+ ISE) 301:
? combine potassium ionophore (2%), KTFPB (0.5%), THF, PVC (33%), and NPOE (65.45%); and
? Then, stir the above mixture until it becomes homogenous solution;
? Drop cast the solution onto the surface of screen-printed electrode (SPE) 301;
c) fabrication of reference electrode 301:
? Dissolve NaCl in 1ml methanol, and stir for 10 minutes;
? Then, add polyvinyl butyral, and stir the mixture again for 15 minutes; and
? Drop-cast the final mixture onto the Ag/AgCl reference electrode 301.
8. The method as claimed in claim 1, wherein said working mechanism of the device comprising steps of:
a) 100 µL of whole blood is introduced into the device;
b) Then, the membrane layer 101 separates plasma, which flows into the microfluidic channels 102;
c) After that plasma reaches the sensing zone 103, where ion-selective electrodes 301 measure analyte concentrations;
d) Results are displayed within 2-5 minutes on screen of the device.