CN2762138Y - Biosensor Test Strip Structure - Google Patents

Abstract

A biosensor test piece structure is provided, a working electrode and an auxiliary electrode are formed on an insulating substrate, an insulating layer covers the insulating substrate, the working electrode and the auxiliary electrode, and the insulating layer partially covers the working electrode and the auxiliary electrode and exposes the reaction area plane of the insulating substrate. An upper pad covering the insulating layer. The biochemical reaction area of the biosensor test piece is formed by the three-dimensional space formed by the working electrode, the auxiliary electrode, the insulating layer and the upper gasket, and the sample to be tested can be quickly drawn into the biochemical reaction area by the biochemical reaction layer to carry out biochemical reaction. The working electrode and the auxiliary electrode are designed in the biochemical reaction area by the circuit printing in tandem, and a sample to be detected firstly contacts the working electrode under the traction of hydrophilic macromolecules in the biochemical reaction layer and the action of convection gaps in the biochemical reaction area and then starts biochemical reaction when reaching the auxiliary electrode.

Description

Biosensor Test Strip Structure

technical field

The utility model relates to a biological sensor test piece, in particular to a structural design of a biological sensor test piece.

Background technique

The biosensor is composed of a biochemical identification element and an electronic signal converter. When the sample to be tested is confirmed by the identification element, a chemical signal is converted into an electronic physical signal by the electronic signal converter, and then analyzed by a series of logical operations. The quantitative digital signal is converted into the concentration of the sample to be tested and output directly.

Most of the current commercial electrochemical biosensors are mainly amperometric biosensors. The electrochemical reaction current of the sample to be tested is obtained by controlling the potential of the working electrode and the reference electrode. The development of such amperometric biosensor devices has been applied to the detection of glucose, cholesterol and other drugs in blood.

Generally, this type of amperometric biosensor is mainly composed of an insulating substrate, a pair of thin film electrodes, an insulating layer and an enzyme biochemical reaction area. The two-pole film electrode test piece refers to a working electrode and an auxiliary electrode. When the sample to be tested is evenly drawn into the biochemical reaction area, the sample to be tested reacts with the enzyme, and the electrons generated after the sample to be tested are oxidized Transferred to the electron transfer medium by the enzyme, and then a controlled and appropriate stable voltage is applied between the two electrodes to initiate the second redox reaction. This stable voltage must be sufficient to drive a diffusion-limited electron oxidation on the surface of the working electrode. , but it will not cause a reverse chemical reaction. After a stable voltage is applied to the working electrode for a period of time, the current generated by it (called Cottrell current) is detected. The current generated by this electrochemical redox is proportional to the sample to be tested. concentration.

When biosensors are applied to the sensing of blood samples, for example, in the traditional analysis method, the blood samples need to be processed beforehand, and it will be more convenient and time-saving to directly use whole blood for detection. In addition, the viscosity and volume of the blood sample will also affect the detection results. For some elderly patients, the fingertip whole blood may be very small, so it is easy to cause uneven blood flow and insufficient blood flow, resulting in artificial testing. error. On the other hand, the deliquescence in the biochemical reaction area of the test piece before and after the detection will also cause the deviation of the reading value. Therefore, it is necessary to develop a device for detecting trace samples and simple error detection technology to avoid the deviation of the detection result.

In order to achieve the above purpose, in addition to the design of the electronic signal conversion circuit and the error detection electronic circuit, it is also necessary to improve the structure of the biosensor to meet the actual needs.

Utility model content

The main purpose of this utility model is to provide a structural improvement of the biosensor test piece, which can make a small volume of the liquid sample to be tested pass through the biosensor test piece through the structural design of the biosensor test piece. The structural design and the characteristics of the immobilized enzyme attachment agent directly use whole blood as the test sample, and quickly draw the sample to be tested and analyzed into its biochemical reaction area.

Another object of the present utility model is to provide a biosensor test piece with high test stability, through the configuration of the auxiliary electrode and the working electrode of the thin film electrode of the test piece, and the biochemical The structural design of the reaction area can increase the stability of its test.

In order to achieve the above object, the biosensor test piece structure provided by the utility model includes:

An insulating substrate, a reaction zone plane is defined on the surface of the insulating substrate, and the three side edges of the reaction zone plane on the upper surface of the insulating substrate are respectively defined as a drop-in side for the sample to be tested, a biochemical reaction start side, and one end edge side;

A working electrode, one end of which extends to the center of the plane of the reaction zone;

An auxiliary electrode, one end of which extends to the starting side of the reaction zone plane biochemical reaction;

an insulating layer, which partially covers the working electrode and the auxiliary electrode, and exposes the reaction zone plane of the insulating substrate, and the insulating layer has a predetermined thickness;

an upper gasket covering the insulating layer;

The three-dimensional space formed by the working electrode, the auxiliary electrode, the insulating layer and the upper pad together forms the biochemical reaction area of the biosensor test piece, and the biochemical reaction layer coated on the plane of the reaction area can be The sample to be tested is quickly pulled and sucked into the biochemical reaction area for biochemical reaction.

A first carbon electrode and a second carbon electrode are respectively formed on the working electrode and the auxiliary electrode, and an enlarged area is formed at the plane of the reaction area of the second carbon electrode extending to the upper surface of the insulating substrate.

The thickness of the insulating layer is between 0.01-0.10 mm, so as to form enough space for the biochemical reaction zone, and assist the sample to be tested to be drawn into the biochemical reaction zone by the hydrophilic polymer in the biochemical reaction layer.

Wherein the insulating layer may further include a pair of blocking pieces respectively arranged at the edge sides of the insulating substrate.

A convection gap is formed between the two blocking sheets.

Wherein the upper gasket is formed with a groove structure at the side where the sample to be tested is dropped corresponding to the upper surface of the insulating substrate to serve as the sample to be tested to drop into the inlet.

The area covered by the upper gasket above the biochemical reaction zone is transparent to serve as a confirmation window, so that users can easily confirm whether the sample to be tested has completely entered the biochemical reaction zone.

The constituent reagents of the biochemical reaction layer include buffer solution, biochemical reaction enzyme, electron transfer medium, polymer adhesion agent and surfactant.

The working electrode and the auxiliary electrode in the biochemical reaction zone are designed by circuit printing one after the other, and the sample to be tested is drawn by the hydrophilic polymer in the biochemical reaction layer and under the action of the convection gap in the biochemical reaction zone. The biochemical reaction starts when it touches the working electrode and then reaches the auxiliary electrode.

Wherein the working electrode and the auxiliary electrode are thin film electrodes.

Through the technical means adopted by the utility model, a biological sensing device with simple operation and measurement and high accuracy can be provided. The special structural design of the utility model makes the micro volume of the liquid sample to be tested, through the structural design of the biosensor and the characteristics of the immobilized enzyme adhesion agent, directly use the whole blood as the detection sample, and quickly test the liquid sample to be analyzed. The sample is dragged and inhaled into its biochemical reaction area to carry out a series of biochemical reactions, which can cooperate with the electronic circuit design and test method connected to the subsequent stage of the biosensor, and further increase the accuracy and accuracy of the biosensing device.

Description of drawings

Fig. 1 shows the three-dimensional exploded view of the biosensor test piece of the present invention;

Fig. 2 shows the perspective view of the utility model biosensor test piece;

Fig. 3 shows a cross-sectional view of section 3-3 in Fig. 2 .

Detailed ways

The specific structural design adopted by the utility model will be further described by the following embodiments and accompanying drawings.

Referring to FIG. 1 , it shows a three-dimensional exploded view of the biosensor test piece of the present invention, and FIG. 2 shows a three-dimensional view of the biosensor test piece. The basic structure of the biosensor test piece 100 of the present utility model includes an insulating base plate 1 (Insulating Base Plate), which is used as the substrate of the biosensor test piece.

The material of the insulating substrate 1 has the characteristics of insulation and heat resistance, and the following materials can be selected as the substrate singly or in combination: polyvinyl chloride, polyethylene glycol terephthalate, polycarbonate ( polycarbonate), polyamide, polyester, nylon, or nitrocellulose.

A pair of thin film electrodes are disposed on the insulating substrate 1, which can be fabricated on the insulating substrate 1 by known screen printing or sputtering techniques. The pair of thin-film electrodes at least includes an anode wire and a cathode wire which are not in contact with each other, serving as a working electrode 21 (working electrode) and an auxiliary electrode 22 (counter electrode) respectively. The working electrode 21 and the auxiliary electrode 22 are made of materials with good electrical conductivity, such as the following materials selected singly or in combination: carbon glue, silver glue, silver/silver chloride glue, gold, platinum or palladium.

A reaction zone plane 11 is defined on the surface of one side end of the insulating substrate 1, and the three side edges of the reaction zone plane 11 on the upper surface of the insulating substrate 1 are respectively defined as a sample drop-in side 12, a The biochemical reaction start side 13 and the end edge side 14 .

One end of the working electrode 21 extends to the position near the central region of the reaction zone plane 11 through an extension section 211, and one end of the auxiliary electrode 22 also extends to the center of the reaction zone plane 11 through an extension section 221. There are 13 places where the biochemical reaction starts. The other end of the working electrode 21 and the auxiliary electrode 22 can be used as a connection area with an electronic signal converter.

A first carbon electrode 31 and a second carbon electrode 32 are respectively formed on the working electrode 21 and the auxiliary electrode 22 . The size, width and layout path of the first carbon electrode 31 and the second carbon electrode 32 are consistent with the size, width and layout path of the working electrode 21 and the auxiliary electrode 22 , and they also include extension sections 311 , 321 respectively. Furthermore, the second carbon electrode 32 also forms an enlarged region 312 at the reaction region plane 11 extending to the upper surface of the insulating substrate 1 .

An insulating layer 4 (Dielectrical Layer) is covered on the first carbon electrode 31 and the second carbon electrode 32 and on the insulating substrate 1 . The insulating layer 4 partially covers the first carbon electrode 31 , the second carbon electrode 32 and the insulating substrate 1 , but does not cover the reaction zone plane 11 on the upper surface of the insulating substrate 1 .

The function of the insulating layer 4 is to protect the electrodes and form a considerable thickness to form a three-dimensional space for the detection sample biochemical reaction zone 6, so as to assist the biochemical reaction layer to quickly draw the sample to be detected into the biochemical reaction zone 6. The thickness of the insulating layer 4 is between 0.01-0.10 mm to form enough space for the biochemical reaction zone 6 , and the auxiliary detection sample is drawn into the biochemical reaction zone 6 by the hydrophilic polymer in the biochemical reaction layer.

The thickness of the insulating layer 4 determines the size of the biochemical reaction zone 6 and the required reaction volume of the sample to be tested. The uniformity of thickness can be controlled by selecting appropriate materials and screen printing technology using stainless steel screen.

The insulating material used for the insulating layer 4 can be selected from the following materials: acrylate, polyester (vinylpolyester), polyamide (polyimide), epoxy resin (epoxy resin), polyvinyl chloride (polyvinyl chloride), polyparaphenylene Polyethylene glycolterephthalate, polycarbonate, or polyester.

The insulating layer 4 may further include a pair of blocking pieces 41 , 42 respectively disposed at the edge side 14 of the insulating substrate 1 . A convection gap 43 is formed between the two blocking pieces 41 , 42 .

On the insulating layer 4, an upper gasket 5 (Lamina) is finally covered and pasted, and the upper gasket 5 forms a groove at the drop-in side 12 of the sample to be measured corresponding to the upper surface of the insulating substrate 1. The structure is used as the drop port 51 of the sample to be tested.

In a preferred embodiment, the area covered by the upper gasket 5 above the biochemical reaction zone 6 is transparent, which can be used as a confirmation window to facilitate users to confirm whether the sample to be tested has completely entered the biochemical reaction zone 6 . The material of gasket 5 on it can be single or mixed and select the following materials: polyvinyl fluoride (polyvinyl chloride), polyethylene terephthalate (polyethylene glycolterephthalate), polycarbonate (polycarbonate), polyamide (polyamide), poly ester (polyester), or nitrocellulose (nitrocellulose).

After the above-mentioned related components are assembled, the front end of the exposed thin-film electrode (ie, the working electrode 21 and the auxiliary electrode 22 ), an insulating layer 4 with a considerable thickness, and the upper surface of the reaction zone plane 11 adjacent to the insulating substrate 1 The three-dimensional space jointly formed by the spacers 5 forms a biochemical reaction zone 6 (also refer to FIG. 3 ).

And on this reaction area plane 11, be coated with one deck biochemical reaction reagent, as biochemical reaction layer (Reaction Layer), its function is to draw the sample to be detected rapidly in the biochemical reaction area 6 and carry out a series of biochemical reactions. The constituent reagents of the biochemical reaction layer include: buffer solution, biochemical reaction enzyme, electron transfer medium (mediator), polymer adhesion agent and surfactant.

Appropriate convection gaps are arranged in the biochemical reaction zone 6 to instantly increase the speed at which the hydrophilic polymer in the biochemical reaction layer pulls the sample to be tested into the biochemical reaction zone 6; the space in the biochemical reaction zone 6 is small enough to make 0.5- The 3.5ul sample to be tested is completely covered.

Furthermore, since the working electrode 21 and the auxiliary electrode 22 are in the biochemical reaction zone 6 in a one-by-one circuit printing design, it can be ensured that the reaction initiation time of the sample to be tested is consistent when it enters the biochemical reaction zone 6 , when the sample to be tested is pulled by the hydrophilic polymer in the biochemical reaction layer and under the action of the convection gap in the biochemical reaction zone 6, it first contacts the working electrode 21 and then reaches the auxiliary electrode 22, the biochemical reaction time will start counting, so as to Increase the stability of its tests.

The above narration is only the description of the preferred embodiments of the present utility model, and all those who are proficient in this technology can make other various improvements according to the above description, but these changes still belong to the creative spirit of the present utility model and the defined patent scope .

Claims (10)

1. a biosensor test piece structure is characterized in that, includes:

One insulated substrate has defined a reaction zone plane on this insulated substrate surface, and this reaction zone plane then is defined as respectively at three lateral margins of this insulated substrate upper surface, and a testing sample splashes into side, a beginning side and an ora terminalis side are opened in a biochemical reaction;

One working electrode, one end extend to this middle section position, reaction zone plane;

One auxiliary electrode, one end extend to this reaction zone plane biochemical reaction and open beginning side place;

One insulation course, its part is covered on this working electrode and the auxiliary electrode, and exposes the reaction zone plane of this insulated substrate, and this insulation course has a preset thickness;

One Upper gasket is covered on this insulation course;

Wherein this working electrode, auxiliary electrode, insulation course, Upper gasket constitute the biochemical reaction zone that the three-dimensional space forms this biosensor test piece jointly.

2. biosensor test piece structure as claimed in claim 1, it is characterized in that, wherein also be formed with one first carbon electrode and one second carbon electrode on this working electrode and the auxiliary electrode respectively, and at this second carbon electrode at the reaction zone plane place that extends to this insulated substrate upper surface, also form an enlarged area.

3. biosensor test piece structure as claimed in claim 1 is characterized in that wherein the thickness of this insulation course is between 0.01-0.10mm.

4. biosensor test piece structure as claimed in claim 1 is characterized in that wherein this insulation course also includes a pair of blocking sheet, is configured in the ora terminalis side place of this insulated substrate respectively.

5. biosensor test piece structure as claimed in claim 4 is characterized in that, wherein forms a pair of ebb interval between these two blocking sheets.

6. biosensor test piece structure as claimed in claim 1 is characterized in that wherein this Upper gasket splashes into the side place at the testing sample corresponding to this insulated substrate upper surface, and being formed with a groove structure is that testing sample splashes into mouth.

7. biosensor test piece structure as claimed in claim 1 is characterized in that, wherein to be covered in the zone of biochemical reaction zone top be transparent to this Upper gasket, as confirming form.

8. biosensor test piece structure as claimed in claim 1 is characterized in that, wherein the composition reagent of this biochemical reaction layer comprises damping fluid, biochemical reaction ferment, electron transfer mediator, the attached outstanding agent of macromolecule and interface activating agent.

9. biosensor test piece structure as claimed in claim 1 is characterized in that, wherein with tandem circuit printed design, testing sample is this working electrode of contact earlier, arrives auxiliary electrode again in this biochemical reaction zone for working electrode and auxiliary electrode.

10. biosensor test piece structure as claimed in claim 1 is characterized in that, wherein this working electrode and auxiliary electrode are membrane electrode.

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