Biosensor for biological sample detection

Abstract

The utility model provides a biosensor for biological sample detection, which comprises a substrate, a conducting layer arranged on the substrate, engraving lines distributed on the conducting layer, and electrodes formed by dividing the engraving lines, the expansion area is formed by at least two sections of mutually-forked carving lines which are formed by forking the joint of the carving line where the expansion area is located and the expansion area, and the expansion area is defined by the mutually-forked carving lines. According to the biosensor, accidental connection between the electrodes can be effectively avoided, and the detection accuracy of the biosensor in the use process and the qualified rate of the biosensor in the production and preparation process are ensured.

Description

Technical Field

[0001] The utility model relates to the field of biomedical detection, in particular to a biosensor. Background Art

[0002] Electrochemical sensors and their associated test instruments for detecting the content of analytes in samples have been widely used in daily disease monitoring. For example, diabetic patients often use electrochemical sensors to monitor their daily blood glucose levels.

[0003] The basic structure of this type of electrochemical sensor includes an electrode system mounted on an insulating substrate. The electrode system includes multiple or various types of electrodes, such as working electrodes and counter electrodes. Reagents that react with the analyte are coated on the corresponding electrodes. A sample interlayer with grooves is positioned on the electrodes, and a cover sheet with air holes covers the sample interlayer. The insulating substrate, interlayer, and cover sheet form a sample inlet channel, and the other end of the electrode system contacts the test instrument. The sample flowing into the sample inlet channel reacts with the reagents on the electrodes to generate electrical signals, which the test instrument uses to determine the test results.

[0004] Electrodes can be formed on an insulating substrate by screen printing. Alternatively, electrodes can be formed by pre-forming a uniform thin-film conductive layer on the insulating substrate and then using a laser etching process. The thin-film conductive layer can be a metal conductive layer such as gold or palladium, or a non-metallic conductive layer such as carbon or conductive glass.

[0005] The properties of the thin film conductive layer will affect the structure, electrode design, manufacturing process, user experience and test performance of the biosensor. If the thin film conductive layer is soft and loose, or has average adhesion to the insulating substrate, the conductive particles may peel off or detach from the conductive layer under the action of external force. The external force can be the shear force on the conductive layer caused by the cutting tool used to cut the semi-finished sensor into single independent sensors during the production of the biosensor, or the external force caused by the scratching of the sensor by the instrument detection tentacles when the user inserts the sensor into the test instrument, or the external force caused by the mutual scratching between the sensors during transportation after the sensor is packaged into a tube. These peeled or detached conductive particles may remain in the nearby engraving lines, causing a short circuit between the two electrodes on both sides of the engraving line that should have been disconnected from each other, and the resulting finished product can only be scrapped.

[0006] pass Figures 1 to 5 The example shown is used to illustrate the effect of conductive particles dropped into the engraved lines on the test.

[0007] Figure 1 The biosensor shown is a biosensor with a thin film conductive layer. For the sake of convenience, the upper cover, the middle layer, etc. are not shown. Figure 1 As shown inFigure 1 As shown, the cutting tool cuts the conductive layer of the biosensor along the preset route to obtain the conductive layer edge lines 21 and 24. The moving route of the cutting tool intersects with the engraved lines 31, 32, 33, 34, 41 and 42. The conductive area A on both sides of the engraved line 41 is separated from the electrode B by the engraved line 41, and the two are disconnected and have no electrical conduction. The electrodes D and E on both sides of the engraved line 34 are separated by the engraved line 34, and the two are disconnected and have no electrical conduction. Figure 2 and Figure 3 respectively Figure 1 are enlarged views of the instrument contact end L and the sample contact end R of the sensor. As shown Figure 2 , when the cutting tool cuts the conductive layer along the preset route to obtain the conductive layer edge line 24, when the cutting tool cuts to the engraved line 34, due to the mechanical shearing force of the cutting tool on the conductive layer, conductive particles X may be peeled off or separated from the conductive layer and remain in the engraved line 34, causing a short circuit between the electrodes D and E due to the conductive particles X. If such a biosensor is found during the quality inspection process of production, it will be treated as a defective product; if a user inserts such a biosensor into a test instrument, the test instrument will automatically report an error and prompt the user that it cannot be used. Figure 3 As shown , when the cutting tool cuts the conductive layer along the preset route to obtain the conductive layer edge line 21, when the cutting tool cuts to the engraved line 41, the peeled conductive particles X may remain in the engraved line 41, causing a short circuit between the electrodes B and the conductive area A, causing the electrode area of the electrode B at the sample contact end to change, which may cause fluctuations in the conduction signal and cause deviations in the sensor test value.

[0008] On the other hand, when a user performs a blood glucose test, the biosensor is inserted into the test instrument, and the contact pins in the test instrument move relative to the sensor, the contact pins may scratch the thin film conductive layer exposed on the biosensor, causing peeled or separated conductive layer particles, and these conductive particles generated by scratching may also cause a short circuit between the two adjacent conductive areas.

[0009] As shown Figure 4 and Figure 5 , the sensor 100 is inserted into the test instrument 200 for sample determination. From the contact of the conductive layer edge line 24 at the sensor instrument contact end to the insertion process of the sensor into the preset position of the instrument (i.e., the test position), the contact pins of the instrument may scratch the conductive layer to some extent in their moving path relative to the sensor, and the conductive layer may have a certain probability of causing the conductive particles to peel off or separate and remain in the nearby engraved line after being stressed. As shown Figure 4As shown, the insertion direction of the sensor relative to the instrument is downward, and the insertion direction of the instrument relative to the sensor is upward. Figure 5 As shown Figure 4 A partial enlarged view of the middle dashed box area. After the sensor is inserted, the test instrument contacts the feet a and β with the electrode F and the conductive area H respectively, and transmits the electrical signal to the test instrument. During the insertion process, the foot a first contacts the sensor conductive layer edge line 24, and the position of the foot a on the conductive layer is marked as a1. When the sensor is inserted into the test position, the position of the foot a on the sensor conductive layer is marked as a2. During the movement of the foot a on the sensor in the direction of a1→a2, the conductive layer of the sensor may be scratched. Due to the factors such as the material of the sensor conductive layer itself or the poor adhesion between the conductive layer and the insulating substrate, when there is an engraved line 49 intersecting the movement path a1→a2 on the sensor, the peeled conductive particles X may be left in the engraved line 49. If the conductive particles X contact the electrode F and the conductive area H on both sides of the engraved line 49 respectively, a short circuit occurs between the electrode F and the conductive area H which are originally separated by the engraved line 49, thereby causing the test failure of the sensor. Since the short circuit occurs during the use of the user, the inaccurate detection result causes the user to misjudge. Content of the utility model

[0010] In the prior art, the conductive particles generated by the thin film conductive layer due to poor adhesion, cutting, scratching and other factors are left in the engraved line, and the sensor in which the originally disconnected electrodes are short-circuited or the sensor in which the electrode size is changed due to the residual conductive particles cannot be used for testing. In order to overcome the problems in the prior art, the utility model also provides a biological sensor, which comprises a substrate, a conductive layer arranged on the substrate, a separation line distributed on the conductive layer, and an electrode formed by the separation line. At least one of the separation lines is provided with an expansion area.

[0011] In some embodiments, the outer edge line spacing of the expansion area is greater than the outer edge line spacing of the separation line connected thereto.

[0012] In some embodiments of the utility model, the expansion area is formed by extending outward from at least one outer edge line of the separation line where the expansion area is located.

[0013] In some embodiments of the utility model, the expansion area is arranged at the end of the separation line where the expansion area is located and the conductive layer edge line. Further, the expansion area is located at the contact end or the sample contact end of the biological sensor. In some embodiments, the separation line intersecting the conductive layer edge line is provided with an anti-short circuit area.

[0014] In some embodiments of the utility model, the expansion area can also be arranged on the moving path of the probe of the testing instrument relative to the biosensor, and is located at the position where the moving path intersects with the separation line where the expansion area is located. In some embodiments, the separation line intersecting with the moving path of the probe is provided with the short-circuit prevention area.

[0015] In some embodiments of the utility model, the expansion area is not provided with a conductive layer. Alternatively, the expansion area is provided with a conductive layer, and the conductive layer in the expansion area is separated from the conductive layer outside the expansion area by the separation line. Further, the expansion area is also provided with a separation line, which divides the conductive layer in the expansion area into multiple areas.

[0016] In some embodiments of the utility model, the expansion area is formed by the separation line where the expansion area is located and the bifurcation of the connection between the expansion area, and is enclosed by the mutually diverging separation lines.

[0017] Further, the separation line is an engraved line.

[0018] The biosensor can further include a middle layer with an open slot, an upper cover, a conductive layer, and a sample inlet channel formed between the open slot and the upper cover, and the sample inlet channel contains a reagent.

[0019] The separation line of the utility model can be an engraved line formed on the thin film conductive layer by laser etching technology, and the conductive layer in the engraved line is removed and exposed to the insulating substrate. The separation line can also be an electrode or a conductive area formed by printing the conductive layer on the insulating substrate according to a certain pattern design by silk screen printing technology, leaving a gap between the electrodes or between the electrodes and the conductive area for separating the electrodes and the conductive area, or using other technologies to produce the separation line.

[0020] The skilled in the art can design the route of the carving line on the conductive layer or set the process parameters of the laser etching of the carving line according to the actual situation, for example, the anti-short circuit line or the anti-short circuit area can be a carving line which is wide enough compared with other carving lines; or a plurality of carving lines can be formed by separating the end of the carving line close to the edge line of the conductive layer, and the edge line of the conductive layer is enclosed; or the line width of the carving line at the end of the intersection with the edge line of the conductive layer is increased to form an anti-short circuit area with the edge line of the conductive layer, or the conductive layer on a certain pattern is integrally stripped by using the laser etching technology to realize the anti-short circuit design at the end of the carving line and the edge line of the conductive layer. The utility model discloses a kind of anti-short circuit lines or anti-short circuit areas, or in other words, an enlarged area is formed in the specific area of the carving line, which can effectively avoid the situation that the conductive area (such as electrode and electrode, conductive area outside electrode and electrode) on both sides of the carving line is connected by the conductive particles remaining on the carving line to cause short circuit, or reduce the probability of short circuit, ensure the stability of the performance of the finished sensor, and improve the finished product qualification rate and yield of the sensor production preparation. The utility model has strong operability and practicality. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 The sensor is not provided with an enlarged area on the carving line.

[0022] Figure 2 Figure 1 An enlarged view of L.

[0023] Figure 3 Figure 1 An enlarged view of R.

[0024] Figure 4 A process schematic diagram of the insertion of the sensor into a testing instrument.

[0025] Figure 5 A partial enlarged view of the insertion of the contact end of the sensor into the instrument, which is an enlarged view of the dashed area. Figure 4

[0026] Figure 6 A disassembled view of the biosensor.

[0027] Figure 7 A flowchart of the manufacturing method of the biosensor.

[0028] Figure 8 A schematic diagram of a semi-finished product after laser etching.

[0029] Figure 9 Figure 8 A schematic diagram of a semi-finished product long strip material containing a plurality of sensor base units Y after cutting.

[0030] Figure 10 Figure 6 ​​​​​Schematic view of the front side of the biosensor conductive layer.

[0031] Figure 11 is a magnified view of 10 at L.

[0032] Figure 12 is a magnified view of 10 at R.

[0033] Figure 13 is a process schematic of a biosensor insertion testing instrument with an enlarged area at the intersection of the scribe line and the foot travel path.

[0034] Figure 14 is a biosensor schematic with an enlarged area at the intersection of the scribe line and the foot travel path.

[0035] Figure 15 is a magnified view of the biosensor of Figure 14 at the contact end.

[0036] Figure 16 is a schematic of the conductive layer of the biosensor of Example 2.

[0037] Figure 17 is a magnified schematic of Figure 16 at L.

[0038] Figure 18 is a magnified schematic of Figure 16 at R.

[0039] Figure 19 is a partial magnified view of the biosensor insertion testing instrument of the present invention.

[0040] Figure 20 is a biosensor schematic with an enlarged area at the intersection of the scribe line and the foot travel path.

[0041] Figure 21 is a magnified view of the biosensor of Figure 20 at the contact end.

[0042] Figure 22 is a schematic of the conductive layer of another biosensor of Example 2.

[0043] Figure 23 is a magnified schematic of Figure 22 at L.

[0044] Figure 24 is a magnified schematic of Figure 22 at R.

[0045] Figure 25 is a schematic of the conductive layer of the biosensor of Example 3.

[0046] Figure 26yes Figure 25 Enlarged schematic diagram at L.

[0047] Figure 27 yes Figure 25 Enlarged schematic diagram at R.

[0048] Figure 28 It is one of the graphic designs for short circuit prevention.

[0049] Figure 29 These are four graphic designs in anti-short circuit design.

[0050] Figure 30 Schematic diagram of a biosensor with an expansion area at the intersection of an engraving line and a tentacle movement path.

[0051] Figure 31 Schematic diagram of a biosensor having an enlarged area at the intersection of an engraved line and a path of movement of a tentacle, wherein the enlarged area also includes an engraved line. DETAILED DESCRIPTION

[0052] The present invention will be described in detail below with reference to specific embodiments.

[0053] Example 1:

[0054] like Figure 6 The biosensor 100 shown includes an insulating substrate 1, a conductive layer 2 arranged on the substrate, and an electrode system formed by dividing the conductive layer by engraving lines. The electrode system includes a working electrode E, a counter electrode D and a reference electrode C. The electrodes have a sample contact end 101 that contacts the sample and a contact end 102 that contacts the test instrument contact. The reagent layer 6 is added to the corresponding electrode at the sample contact end, and the middle partition layer 8 with an open groove 81 covers the sample contact end of the electrode. The upper cover 9 covers the middle partition layer 8, thereby forming an injection channel between the conductive layer 2, the open groove 81 and the upper cover 9. There are electrodes and reagents in the injection channel. The upper cover 9 has a vent 91. The vent is located on the open groove and is used to discharge gas in the injection channel after sample addition.

[0055] The electrodes are formed by dividing the conductive layer 2 by engraving lines, which are insulating gaps left after the conductive material is removed. Figure 6 The corresponding front view of the conductive layer 2 can be seen in the attached Figure 10 The working electrode E is surrounded by engraved lines 32, 34, 35, 36, 42, 43, and 45. The counter electrode D is surrounded by engraved lines 33, 34, 35, 36, 37, 38, 43, 44, 45, 46, and 47. The reference electrode C is surrounded by engraved lines 31, 33, 35, 41, 42, and 44.

[0056] The reagent is dispensed on the corresponding electrode of the sample contact end, the electrode extends from the sample contact end to the sensor contact end, and the electrical signal generated by the reaction of the analyte and the reagent is conducted to the sensor contact end, and then the test result is returned to the user through the instrument.

[0057] For example, a method for manufacturing a biosensor as shown in Figure 7 For example, a method for manufacturing a biosensor as shown in Figure 6 The method comprises the following steps.

[0058] Step 1: Laser etching of electrode pattern: according to the pre-designed electrode pattern, laser etching is performed on the conductive layer of the raw material with an insulating substrate and a conductive layer to form engraved lines to form an electrode pattern, thereby obtaining an electrode big card of a plurality of sensor basic units Y. Step 2: Adding reagent layer: configuring a detection reagent, and adding the prepared reagent to the corresponding electrode where the reagent needs to be added. Step 3: Attaching the middle layer 8 to each sensor basic unit Y. Generally, the middle layer is placed at the sample contact end of the biosensor. Step 4: Attaching the upper cover 9 to the middle layer 8 and rolling. Step 5: After the upper cover is attached, the color layer is attached and rolled on the upper cover to obtain a semi-finished big card. Step 6: Cutting: using a cutting tool to cut the semi-finished big card along the preset cutting line to obtain a finished biosensor.

[0059] Specifically, step 1 uses laser etching technology to etch the conductive layer 2 on the surface of the insulating substrate to form a plurality of engraved lines 31-38, engraved lines 41-49, and the conductive layer is removed in the engraved lines to expose the insulating substrate. The engraved lines are divided to form a working electrode E, a counter electrode D and a reference electrode C on the conductive layer. After laser etching is completed, an electrode big card is obtained, which comprises a plurality of sensor basic units Y for manufacturing a finished biosensor arranged side by side on the insulating substrate, each sensor basic unit Y comprising an insulating substrate, an electrode system formed by dividing the conductive layer by the engraved lines, the engraved lines and other conductive areas formed by etching.

[0060] The laser cutting instrument can apply different laser etching parameters to the engraved lines, and the line width of the engraved lines ranges from 0.020mm to 0.300mm, and the line width of the engraved lines in the present example is 0.080mm.

[0061] The material of the conductive layer 2 can be a conductive metal or a conductive non-metal, including but not limited to gold, silver, platinum, palladium, carbon, graphite, conductive glass, or a mixture thereof. The conductive layer can be formed by printing, coating, electroplating, sputtering, etc. In the present example, the conductive layer is formed by coating a conductive carbon layer (also known as carbon film), and the thickness of the conductive carbon layer can be 1-30μm, and the thickness used in the present example is about 8μm. The resistance of the conductive layer is 10Ω / □-100Ω / □, and the preferred resistance in the present example is 30Ω / □.

[0062] The reagent contacts the sample in the sample introduction channel and reacts with the substance to be detected in the sample. The sample introduction channel is formed between the open slot 81 and the cover 9, and the surface of the cover facing the sample introduction channel is a hydrophilic layer material. The material of the spacer layer is, for example, PET as a base, and is coated with an acrylic resin-based adhesive material. The thickness of the spacer layer is generally 75 μm to 150 μm, and the width of the open slot is generally 0.7 mm to 1.8 mm. In the present example, the thickness of the spacer layer is preferably 100 μm, and the width of the open slot is preferably 1.2 mm.

[0063] The shape of the vent hole in the cover can be circular, square, rectangular, line-shaped, or other shapes, and in the present example, the shape of the vent hole is preferably rectangular. In the present example, the hydrophilic material is preferably 9901P manufactured by 3M. The vent hole in the cover ensures that the original air in the cavity is smoothly discharged when the blood sample flows into the sample introduction channel, and ensures that the sample can smoothly flow into the cavity.

[0064] The color layer serves to easily identify the product and protect the reagent strip from damage due to scratching. If the cover itself is printed with the product name, it serves a similar function to the color layer, and the color layer is not needed. Alternatively, the biosensor can not use a color layer.

[0065] In the production process, the material that has been attached to the spacer layer and the cover and has a plurality of sensor base units Y is generally referred to as a semi-finished large card, or the material that has completed steps 1 to 4 or steps 1 to 5 is referred to as a semi-finished large card.

[0066] The cutting tool used in step 6 is cut along the predetermined cutting line. As shown in Figure 8 , the cutting tool cuts the semi-finished large card along the positions indicated by the dashed line 50 and the dashed line 51 in Figure 8 to obtain the finished biosensor. Suitable cutting methods include, but are not limited to, hobbing, die cutting, and chopping. In the present example, a hobbing cutter is used to cut the semi-finished large card as shown in Figure 8 along the horizontal dashed line 50 to obtain a semi-finished long strip material as shown in Figure 9 containing a plurality of sensor base units Y, and then the hobbing cutter is used to cut the semi-finished long strip material along the vertical dashed line 51 to obtain the finished biosensor. The cutting process of step 6 is described in Figure 8 and Figure 9 . In order to more intuitively illustrate the cutting position of the hobbing cutter, Figure 8 and Figure 9 do not show the spacer layer and the cover. The dashed lines 50 and 51 marked on Figure 8 and Figure 9 do not exist in the actual product processing process.

[0067] The conductive particles remaining in the engraved line due to the mechanical shearing force of the cutting tool on the conductive layer are difficult to be observed, and the resulting risk is mainly that short circuit of adjacent electrodes or electrical conduction between the electrodes and the conductive area outside the electrodes can be caused. In order to eliminate or reduce the probability of such unqualified sensors, the utility model adds an anti-short circuit line or an anti-short circuit area on the related engraved line, that is, an anti-short circuit engraved line is added or an expansion area is formed by expanding the engraved line in a certain area of the engraved line, the line width of the expansion area is greater than the line width of the engraved line where the expansion area is located. For example, the line width of part of the area of the engraved line is moderately widened to reduce the risk of short circuit caused by the conductive particles, and the local line width of the engraved line is moderately widened to form an anti-short circuit area. Even if the conductive particles peeled off or separated fall into the anti-short circuit area, they cannot simultaneously contact the electrodes or the conductive area on both sides of the engraved line, thereby avoiding short circuit between the electrodes on both sides of the engraved line or between the electrodes and the conductive area. In the embodiment, the width of the anti-short circuit area is 0.14mm-0.3mm, and the preferred value in the example is 0.2mm. The utility model can reduce the risk of accidental short circuit of the biosensor.

[0068] As shown in Figure 10 and Figure 10 Enlargement of the area L of the contact end of the biosensor Figure 11 As shown in the figure, the anti-short circuit area 71 is the area where the line width of the engraved line 34 is increased at the end of the intersection with the conductive layer edge line 24. The anti-short circuit area is also called an engraved line expansion area, and is simply referred to as an expansion area. The outer edge line spacing of the expansion area is greater than the outer edge line spacing of the engraved line connected thereto. As shown in the figure, at the position close to the conductive layer edge line 24, the two outer edge lines 341 and 342 of the engraved line 34 are expanded to the left and right respectively, and then the anti-short circuit area 71 is formed between the two outer edge lines 343 and 344 which are expanded outward at the position close to the conductive layer edge line 24. The anti-short circuit area 71 is connected with the engraved line 34, and the line width of the anti-short circuit area 71 formed by etching is greater than the width of the engraved line 34. In this example, the conductive layer in the anti-short circuit area 71 is removed by laser etching. The engraved line width of the anti-short circuit area 71 is set to be greater than the size of the conductive particles X peeled off in general cases, so that even if there are conductive particles X remaining in the engraved line 71 when the cutting tool cuts the conductive layer edge line 24 along the preset route, the electrical conduction between the electrode D and the electrode E will not be caused. The anti-short circuit area can avoid short circuit between the two electrodes on both sides of the engraved line which are originally disconnected from each other or reduce the risk of short circuit between the two electrodes due to the conductive particles remaining in the engraved line.

[0069] As shown in Figure 10 and Figure 10 Enlargement of the area R of the sample contact end of the biosensor Figure 12As shown, the anti-short-circuit region 71 is the area where the width of the engraved line 41 increases at the intersection with the conductive layer edge 21. As shown in the figure, near the conductive layer edge 21, the two outer edges 411 and 412 of the engraved line 41 extend upward and downward, respectively. Furthermore, the anti-short-circuit region 71 is formed between the two outer edges 413 and 414 extending outward near the conductive layer edge 21. The anti-short-circuit region 71 is connected to the engraved line 41, and the width of the anti-short-circuit region 71 formed by etching is greater than the width of the engraved line 41. In this example, the conductive layer within the anti-short-circuit region 71 is removed by laser etching. The engraved line width of the anti-short-circuit region 71 is set to be larger than the size of the conductive particles X typically removed. Even if the conductive particles X remain in the engraved line 71 when the cutting tool cuts along the predetermined path to obtain the conductive layer edge 21, electrical conduction between the electrode B and the conductive area A will not occur. The anti-short circuit area can prevent the disconnected electrodes on both sides of the engraving line and the conductive areas outside the electrodes from short circuiting due to residual conductive particles, or reduce the risk of short circuiting between two electrodes.

[0070] like Figures 13 to 15 As shown, the electrode F and conductive area H on sensor 100 are separated by an engraved line 49. The area where the instrument's contact pin's movement path intersects with engraved line 49 is defined by an anti-short-circuit zone 72. Specifically, the width of engraved line 49 in this area increases to form anti-short-circuit zone 72, and the width of anti-short-circuit zone 72 is greater than the width of engraved line 49 where the anti-short-circuit zone is located. When sensor 100 is inserted into a test instrument, the instrument's contact pin contacts the sensor's contact end edge 24. The position of the contact pin on the conductive layer at this time is denoted as α1. After the sensor is inserted into the test position, the position of the contact pin on the conductive layer is denoted as α2. As the contact pin moves along α1 to α2 on the sensor, it may come into contact with the conductive layer, causing scraping and shedding of conductive particles X. Because the width of anti-short-circuit zone 72 is greater than that of conductive particles X, if free conductive particles X remain within anti-short-circuit zone 72, the presence of conductive particles X will prevent the connection between electrode F and conductive area H, thereby preventing a short circuit.

[0071] Example 2

[0072] The laser etching equipment has extremely high user-defined modes and good precision control capabilities. The graphics obtained by laser etching are consistent with the design, or the deviation between the two is within a reasonable range. The conductive layer on the insulating substrate is vaporized, melted or disintegrated by the high energy or high temperature generated by the laser focusing, exposing the insulating substrate to form an engraving line. The width of the engraving line formed by laser etching is limited by the properties of the laser etching equipment or the conductive layer, and cannot be infinitely increased. In this embodiment, an anti-short-circuit area is formed by splicing engraving lines with appropriate line widths together, that is, an anti-short-circuit area composed of multiple engraving lines is etched out by laser etching technology. Laser etching technology can also realize the etching of a certain graphic, and the implementation method is similar to completely peeling off and removing the conductive layer on the graphic. Based on the etching method of the above-mentioned laser etching equipment, this embodiment is combined with Figure 14 In this example, lift-off is used to completely etch and lift off the conductive layer on a certain pattern using laser etching technology.

[0073] like Figures 16 to 18 The anti-short circuit area in the sensor shown is formed by peeling off the engraving line at the end where it intersects with the edge of the conductive layer according to a pre-set pattern and enclosing it together with the edge of the conductive layer. Figure 16 and Figure 16 Enlarged schematic diagram of the contact end area L of the biosensor shown Figure 17 The anti-short-circuit zone 73 connected to the engraved line 34 is semicircular and is obtained by completely removing all conductive layers within this semicircular area through laser stripping. As shown in the figure, near the conductive layer edge 24, the two vertical outer edges of the engraved line 34 extend to the left and right, respectively, forming arc-shaped outer edges. Furthermore, the semicircular anti-short-circuit zone 73 is formed between the two outer edges extending outward near the conductive layer edge 24. When the cutting tool cuts along the preset path and obtains the sensor conductive layer edge 24, conductive particles X produced by scratching may remain in the anti-short-circuit zone 73. Because the anti-short-circuit zone 73 is larger than the conductive particles X and is insulated, the conductive particles X cannot simultaneously contact electrodes D and E, causing electrical continuity between them. The presence of the conductive particles X prevents short circuits between electrodes D and E, which are disconnected from each other by the engraved line 34. This design effectively improves the sensor's yield rate and ensures the accuracy of detection performance.

[0074] like Figure 16 and Figure 16 Enlarged view of the sensor sample contact end area R Figure 18The anti-short-circuit zone 73 connected to the engraved line 41 is semicircular and is obtained by completely removing all conductive layers within this semicircular area through laser ablation. As shown in the figure, near the conductive layer edge 21, the two outer edges of the engraved line 41 extend upward and downward, forming arc-shaped outer edges. Furthermore, the semicircular anti-short-circuit zone 73 is formed between the two outer edges extending outward near the conductive layer edge 21. When the cutting tool cuts along the preset path and obtains the sensor conductive layer edge 21, conductive particles X produced by scratching may remain in the anti-short-circuit zone 73. Due to the large size and insulation of the anti-short-circuit zone 73, the conductive particles X cannot electrically connect the electrode B and the conductive area A outside the electrode B. The electrode B and the conductive area A, which are separated by the engraved line 41 and are disconnected from each other, will not be short-circuited by the conductive particles X, thereby maintaining the size of the electrode B, improving the sensor's yield rate, and ensuring the accuracy of the finished product's performance.

[0075] like Figures 19 to 21 As shown, the electrode F on sensor 100 and the conductive area H at the contact end are separated by an engraved line 49. A circular anti-short-circuit zone 74 is defined where the instrument's contact path intersects with engraved line 49. Specifically, the width of engraved line 49 in this area increases to become anti-short-circuit zone 72. This anti-short-circuit zone 74 is wider than the width of engraved line 49 where it resides. This anti-short-circuit zone 74 is created by completely removing all conductive layers within the circular area through laser ablation. When sensor 100 is inserted into a test instrument, the instrument's contact contacts the sensor's contact end edge 24. The position of the contact on the conductive layer at this point is denoted as α1. When the sensor is inserted into the test position, the position of the contact on the conductive layer is denoted as α2. As the contact moves along α1 to α2 on the sensor, it may contact the conductive layer, causing scraping between the two, resulting in the detachment of conductive particles X. These detached conductive particles X may remain within anti-short-circuit zone 74. Since the width of the anti-short circuit area 74 is greater than the conductive particles X, the presence of the conductive particles X will not cause a short circuit between the electrode F and the conductive area H, thereby reducing the probability of a short circuit caused by the contact pins scraping the conductive layer.

[0076] The short-circuit protection area can be designed as follows Figure 16 and Figure 21 The semicircle or circle shown can also be Figure 22 The triangle shown in Example 1 Figure 6 The anti-short-circuit area can also be realized by the laser lift-off technology in this embodiment. Figures 22 to 24 The design of the anti-short circuit area is based on laser etching technology, which uses a laser etching machine to peel off the pattern through engraving lines with appropriate spacing, thereby forming Figure 22The short-circuit prevention area 75 shown is similar to a triangle. The short-circuit prevention area of ​​other shapes can also be obtained by utilizing the laser stripping mode of the laser etching machine.

[0077] Example 3

[0078] like Figures 25 to 27 In the biosensor shown, the short-circuit prevention area 76 located at the sample contact end and the contact end is surrounded by a plurality of engraved lines and the edge lines of the conductive layer.

[0079] like Figure 26 As shown, the engraved line 34 used to separate electrodes D and E forks at its intersection with the conductive layer edge 24 to form multiple engraved lines 34a, 34b, and 34c. In this example, at a location near the conductive layer 24, the outer edges 341 and 342 of the engraved line 34 extend diagonally to the left and right, respectively, to the conductive layer edge 24. Thus, the outer edges 341 and 342 of the engraved line 34 and the conductive layer edge 24 enclose an anti-short circuit area 76. The engraved lines 34a and 34c, along with the conductive layer edge 24, enclose the anti-short circuit area 76, while the engraved lines 34b and 34c, along with the conductive layer edge 24, enclose the anti-short circuit area 76. In this example, the conductive layer within the anti-short circuit area 76 is not removed. The engraved lines 34a, 34b, and 34c can also be referred to as anti-short circuit engraved lines. When the cutting tool cuts along the preset cutting line to form the sensor conductive layer edge 24, conductive particles X may remain in the engraved line 34c. The presence of the conductive particles X causes the short-circuit prevention areas 76 on either side of the engraved line 34c, which were originally disconnected from each other, to become electrically conductive. Engraved line 34a is the section of engraved line 34 close to the conductive layer edge. In the prior art, without engraved lines 34a and 34b, the previously disconnected electrodes D and E would become electrically conductive, causing a short circuit between the sensor electrodes D and E, resulting in scrapped products or inaccurate testing. In this embodiment, due to the presence of the anti-short-circuit engraved lines 34a and 34b, only the two short-circuit prevention areas are electrically conductive, while electrodes D and E remain disconnected from each other. At this point, the sensor electrodes D and E are not affected by the residual conductive particles X, thereby ensuring the performance and yield of the finished sensor.

[0080] like Figure 27As shown, the engraved line 41 for separating the electrode B and the conductive area A is forked into a plurality of engraved lines 41a, 41b and 41c at the end portion intersecting with the conductive layer edge line 21. In the present example, the outer edge lines 411 and 412 of the engraved line 41 extend obliquely upward and obliquely downward respectively to the conductive layer edge line 24 at the position close to the conductive edge line 21, so that the outer edge lines 411 and 412 of the engraved line and the conductive layer edge line 24 enclose a short-circuit prevention area. Among them, the engraved line 41a, 41c and the conductive layer edge line 21 jointly enclose a short-circuit prevention area 76, and the engraved line 41b, 41c and the conductive layer edge line 21 jointly enclose a short-circuit prevention area 76. In the present example, the conductive layer in the short-circuit prevention area 76 is not removed. The engraved lines 34a, 34b and 34c can also be called short-circuit prevention engraved lines. When the cutting tool cuts the conductive layer edge line 21 along the preset cutting line, it is possible that conductive particles X remain in the engraved line 41c. The presence of the conductive particles X makes the electrode B and the conductive area A, which are originally disconnected on both sides of the engraved line 41c, electrically conductive. Without the engraved lines 41a and 41b, the electrode B and the conductive area A, which are originally disconnected, are electrically conductive, so that the area of the sensor electrode B changes, thereby causing the deviation of the test result. In the present embodiment, due to the presence of the engraved lines 41a and 41b, the conductive particles X falling in the engraved line 41c only electrically connect the two short-circuit prevention areas, and the electrode B and the conductive area A are still in the disconnected state. At this time, the electrode area of the sensor electrode B is not affected by the residual conductive particles X, thereby ensuring the performance and yield of the finished sensor.

[0081] As shown in FIG. 4, the cutting tool cuts the conductive layer edge line 24, 21 along the preset cutting line, and the conductive particles X are also likely to remain in the engraved lines 34a, 34b, 34c and the engraved lines 41a, 41b, 41c. However, only when the conductive particles X remain in the engraved lines 34a, 34b, 34c and the engraved lines 41a, 41b, 41c at the same time, the electrode D and the electrode E, and the electrode B and the conductive area A outside the electrode B are electrically conductive. Figure 26 Figure 27 As shown in FIG. 4, the cutting tool cuts the conductive layer edge line 24, 21 along the preset cutting line, and the conductive particles X are also likely to remain in the engraved lines 34a, 34b, 34c and the engraved lines 41a, 41b, 41c. However, only when the conductive particles X remain in the engraved lines 34a, 34b, 34c and the engraved lines 41a, 41b, 41c at the same time, the electrode D and the electrode E, and the electrode B and the conductive area A outside the electrode B are electrically conductive.

[0082] In Figure 28 ​In the example shown, the engraved line 34 used to separate electrode D and electrode E forks at the end portion where it intersects with the conductive layer edge 24, forming multiple engraved lines 34a and 34b. Near the conductive layer edge 24, the outer edges 341 and 342 of the engraved line 34 extend diagonally to the left and right, respectively, to the conductive layer edge 24. Thus, the outer edges 341 and 342 of the engraved line 34 and the conductive layer edge 24 enclose an anti-short circuit area 76, which is free of other engraved lines. The conductive layer within the anti-short circuit area 76 is not removed by laser etching. Conductive particles X falling within this anti-short circuit area cannot establish electrical continuity between electrode D and electrode E. When the cutting tool cuts along the predetermined cutting line to form the conductive layer edge 24, conductive particles X may remain in the engraved lines 34a and 34b. However, electrical continuity between electrode D and electrode E will only be established if and only if conductive particles X remain in both 34a and 34b.

[0083] Compared with the design without anti-short circuit area, Figure 26 、 27 The technical solutions of 28 can reduce the probability of electrical conduction between electrodes or between electrodes and conductive layers other than electrodes. Figure 28 The scheme shown, Figure 26 and Figure 27 The short-circuit protection effect of the solution shown will be better.

[0084] The shapes, numbers, angles between the multiple engraving lines obtained by separating one engraving line and the starting positions of the separation can be arranged according to actual conditions. For example, Figure 29 In the shape shown, electrodes D and E are separated by engraved lines 34, and engraved lines 34a, 34b, and / or 34c form an anti-short-circuit area 76. Conductive particles X remaining in engraved lines 34c or in the anti-short-circuit area do not cause a short circuit between electrodes D and E, thereby ensuring the performance accuracy of the finished sensor.

[0085] Multiple engraving lines are bifurcated from one engraving line to form an anti-short circuit area, which can also be set on the moving path of the test instrument contact foot on the biosensor. Figure 30 In the biosensor shown, an anti-short-circuit zone is provided near the intersection of the engraved line 49 and the moving path of the testing instrument's feeler. The engraved line 49 bifurcates into two engraved lines 49a and 49b near the intersection, and then the engraved lines 49a and 49b protrude outward and surround before reconnecting to the engraved line 49. The enlarged circular area 77 formed by the engraved lines 49a and 49b is the anti-short-circuit zone. The diameter of the enlarged area is larger than the conductive particles X. If the conductive particles X remain in the anti-short-circuit zone 77, the presence of the conductive particles X will not cause a short circuit between the electrode F and the conductive area H, thereby reducing the risk of short circuits caused by the feeler scratching the conductive layer. Figure 31 The biosensor shown isFigure 30 The setting is basically the same, except that the anti-short circuit area near the intersection of the engraved line 49 and the test instrument pin movement path is that the engraved line 49 is bifurcated into three engraved lines 49a, 49b and 49c near the intersection. Figure 30 The anti-short circuit scheme shown in the prior art, Figure 31 The anti-short circuit effect of the example is better.

[0086] The skilled person can consider various factors such as production efficiency and anti-short circuit effect, and select a suitable anti-short circuit area pattern to make a biosensor, thereby improving the qualified rate of the finished sensor and ensuring the detection accuracy of the sensor.

[0087] The biosensor produced by the method has a high qualified rate. After a plurality of performance tests, the biosensor prepared detects samples, and the detection result meets the relevant provisions of the product performance. The biosensor can be used for detecting physiological indexes such as blood glucose, kidney function and blood lipid.

Claims

1. A biosensor for detecting a biological sample, comprising a substrate, a conductive layer disposed on the substrate, a separation line distributed on the conductive layer, and an electrode formed by being divided by the separation line, characterized in that, At least one of the separation lines is provided with an enlarged area, and the enlarged area is formed by at least two segments of the separation line diverging from the connection between the separation line and the enlarged area.

2. The biosensor of claim 1, wherein, The enlarged area is arranged at the end of the separation line where the enlarged area is located and the edge line of the conductive layer meets.

3. The biosensor of claim 2, wherein, The enlarged area is arranged at the contact end of the biosensor or the sample contact end of the biosensor.

4. The biosensor of claim 1, wherein, The enlarged area is arranged on the moving path of the contact pin of the testing instrument relative to the biosensor, and is located at the position where the moving path and the separation line where the enlarged area is located meet.

5. The biosensor of claim 4, wherein, The separation line intersecting with the edge line of the conductive layer is provided with the enlarged area, or the separation line intersecting with the moving path of the contact pin is provided with the enlarged area.

6. The biosensor according to one of claims 1 to 4, characterized in that The enlarged area is further provided with a segment of the separation line, which divides the conductive layer in the enlarged area into multiple areas.

7. The biosensor according to one of claims 1 to 5, characterized in that The separation line is an engraved line.

8. The biosensor according to one of claims 1 to 5, characterized in that The biosensor further comprises a middle separation layer with an open slot, a cover, and a sample inlet channel formed between the conductive layer, the open slot and the cover, and the sample inlet channel contains reagents.

9. The biosensor of claim 6, wherein, The separation line is an engraved line.

10. The biosensor of claim 6, wherein, The biosensor further comprises a middle separation layer with an open slot, a cover, and a sample inlet channel formed between the conductive layer, the open slot and the cover, and the sample inlet channel contains reagents.

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