Preparation method of implantable sensor

Abstract

The invention relates to a preparation method of an implantable sensor. The preparation method comprises the following steps: printing or printing a pattern of a first electrode on a substrate by adopting first conductive ink; printing or printing a pattern of the substrate on the pattern of the first electrode by adopting a liquid polymer, reserving a first through hole penetrating through the substrate, and then curing; printing or printing a pattern of a second electrode on the substrate by adopting second conductive ink, and then curing; and the substrate is peeled off, the two-electrode implantable sensor is obtained, and the first electrode and the second electrode of the implantable sensor can be connected with the connector on the same surface through the first through hole. The implantable sensor is constructed in a layer-by-layer preparation mode, and the first through hole penetrating through the substrate is reserved when the substrate is prepared, so that the substrate does not need to be cut and perforated, the consistency and the yield can be effectively improved, the process can be effectively simplified, the cost can be effectively reduced, and large-scale production is easy to realize.

Description

[0001] This application is a divisional application of the application with the application date of December 29, 2022, the application number of 202211703800.0, and the invention name of "Preparation method of implantable sensor". TECHNICAL FIELD

[0002] The present application relates to the technical field of sensors, in particular to a preparation method of an implantable sensor. BACKGROUND

[0003] The implantable sensor generally uses a flexible polymer as a substrate, and a two-electrode system composed of a working electrode and a counter electrode, or a three-electrode system composed of a working electrode, a counter electrode and a reference electrode is arranged on a single side of the substrate by a plane dislocation method. However, since the implantable sensor needs to be implanted in the body, the overall size is limited, which leads to a limited area of the working electrode when arranged on a single side, thereby reducing the sensitivity and affecting the measurement accuracy.

[0004] Although printing the electrode system on both sides of the substrate can increase the area of the working electrode under the same size, thereby improving the sensitivity of the implantable sensor and making the measurement result more accurate. However, printing the electrode system on both sides of the substrate not only complicates the printing process, but also requires cutting and opening holes in the substrate, and the connector can connect the electrodes on both sides at the same side of the substrate, which leads to poor stability of the implantable sensor, thereby leading to poor consistency and low yield of the implantable sensor. SUMMARY

[0005] Therefore, it is necessary to provide a preparation method of an implantable sensor to solve the above problems, which does not need to cut and open holes, can effectively improve the consistency and yield, and can effectively simplify the process, reduce the cost, and be easy to realize large-scale production.

[0006] In order to achieve the above purpose, the technical scheme adopted by the present application is as follows: a preparation method of an implantable sensor, the preparation method comprising the following steps:

[0007] printing or printing a pattern of a first electrode on a substrate by using a first conductive ink;

[0008] printing or printing a pattern of a substrate on the pattern of the first electrode by using a liquid polymer, reserving a first through hole penetrating through the substrate, and then curing;

[0009] printing or printing a pattern of a second electrode on the substrate by using a second conductive ink, and then curing;

[0010] peeling off the substrate to obtain a two-electrode implantable sensor, and the first electrode and the second electrode of the implantable sensor can be connected to the connector on the same surface by using the first through hole.

[0011] In one embodiment, the first conductive ink and the second conductive ink are independently selected from at least one of carbon paste, silver paste, platinum paste, gold paste, silver / silver chloride paste, and platinum-carbon mixed paste.

[0012] In one embodiment, the liquid polymer is selected from at least one of liquid polyethylene terephthalate, liquid polymethyl methacrylate, liquid polycarbonate, liquid polytetrafluoroethylene, liquid polyethylene, liquid polyvinyl chloride, and liquid polyimide.

[0013] In one embodiment, the substrate has a thickness of 20 μm to 500 μm.

[0014] In one embodiment, the through hole has a diameter of 20 μm to 1500 μm.

[0015] In one embodiment, before peeling off the substrate, the method further comprises:

[0016] printing or patterning a second electrode on the substrate using a third conductive ink, and curing the third conductive ink to form the second electrode;

[0017] printing or patterning a third electrode on the substrate using a third conductive ink, and curing the third conductive ink to form the third electrode, wherein the first electrode, the second electrode, and the third electrode of the implantable sensor are capable of being connected to the connector on the same surface through the first through hole and the second through hole.

[0018] In one embodiment, the insulating paste is selected from thermally cured insulating paste or ultraviolet cured insulating paste.

[0019] In one embodiment, the third conductive ink is silver / silver chloride paste.

[0020] In one embodiment, before the step of printing or patterning the first conductive ink on the substrate, the method further comprises forming a sacrificial layer on the substrate.

[0021] In one embodiment, the sacrificial layer is made of photoresist, hydrogel, or water-soluble polymer.

[0022] In the preparation method, the implantable sensor is constructed by layer-by-layer preparation, and the first through hole penetrating through the substrate is reserved when the substrate is prepared, so that the first electrode and the second electrode of the implantable sensor can be connected with the connector on the same surface through the first through hole, without cutting and opening the substrate, which can effectively improve the consistency and yield, and effectively simplify the process, reduce the cost, and easily realize large-scale production. In addition, compared with the method of printing electrodes on both surfaces of the substrate, the preparation method of the present application does not need to turn over the substrate manually or by equipment, which reduces the requirements of the equipment, and the electrode patterning is flexible and the alignment is more accurate. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments described in the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0024] Figure 1 The plane view of the surface where the first electrode of the implantable sensor of an embodiment of the present application is located;

[0025] Figure 2 The plane view of the surface where the second electrode of the implantable sensor shown in the present application is located; Figure 1

[0026] Figure 3 The structure schematic view of the working end of the implantable sensor shown in another embodiment of the present application.

[0027] In the figure: 20, first electrode; 30, substrate; 301, first through hole; 40, second electrode; 50, insulating layer; 60, third electrode. DETAILED DESCRIPTION

[0028] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail below. In the following description, a lot of specific details are set forth in order to fully understand the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present application, therefore the present application is not limited by the specific embodiments disclosed below.

[0029] ​Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description herein is for describing specific embodiments or examples only and is not intended to be limiting. As used in this patent, the term "and / or" includes any and all combinations of one or more of the associated listed items. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description herein is for describing specific embodiments or examples only and is not intended to be limiting. As used in this patent, the term "and / or" includes any and all combinations of one or more of the associated listed items. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description herein is for describing specific embodiments or examples only and is not intended to be limiting. As used in this patent, the term "and / or" includes any and all combinations of one or more of the associated listed items. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description herein is for describing specific embodiments or examples only and is not intended to be limiting. As used in this patent, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0030] In conjunction with Figures 1 to 2 As shown in the figure, the preparation method of the implantable sensor according to an embodiment of the present application comprises the following steps:

[0031] S1, printing or printing the pattern of the first electrode 20 on the substrate by using the first conductive ink;

[0032] S2, printing or printing the pattern of the substrate 30 on the pattern of the first electrode 20 by using the liquid polymer, and reserving the first through hole 301 penetrating through the substrate 30, and then curing;

[0033] S3, printing or printing the pattern of the second electrode 40 on the substrate 30 by using the second conductive ink, and then curing;

[0034] S4, peeling off the substrate to obtain a two-electrode implantable sensor, and the first electrode 20 and the second electrode 40 of the implantable sensor can be connected to the connector on the same surface through the first through hole 301.

[0035] In step S1, the substrate is generally selected from a glass substrate, a plastic substrate or a metal substrate, preferably a glass substrate, a polytetrafluoroethylene substrate or the like non-stick substrate, which is beneficial to the peeling effect between the substrate and the implantable sensor.

[0036] The substrate and the implantable sensor can be directly peeled off, or a sacrificial layer can be prepared first, and then removed by wet etching or the like to achieve the purpose of peeling off. When using the sacrificial layer, the sacrificial layer can be formed on the substrate first, wherein the material of the sacrificial layer is selected from photoresist, hydrogel or water-soluble polymer.

[0037] It can be understood that the substrate can be cleaned and dried before use.

[0038] In step S1, the first conductive ink is selected from at least one of carbon paste, silver paste, platinum paste, gold paste, silver / silver chloride paste, and platinum-carbon mixed paste. When the first conductive ink is used to print or print the pattern of the first electrode 20 on the substrate, the pattern of the first electrode 20 includes the pattern of the contact area 20A and the pattern of the working area 20B. After printing or printing, the first conductive ink pattern is dried for a period of time, so that the first conductive ink pattern does not flow, and the drying method can be air drying or the like. Then step S2 is performed, the pattern of the substrate 30 is printed or printed by using the liquid polymer, and the two are simultaneously cured, so that the adhesion between the obtained first electrode 20 and the substrate 30 is better and is not easy to fall off.

[0039] Optionally, the liquid polymer is selected from at least one of liquid polyethylene terephthalate, liquid polymethyl methacrylate, liquid polycarbonate, liquid polytetrafluoroethylene, liquid polyethylene, liquid polyvinyl chloride, or liquid polyimide.

[0040] In step S3, the second conductive ink is selected from at least one of carbon paste, silver paste, platinum paste, gold paste, silver / silver chloride paste, and platinum-carbon mixed paste. When the second conductive ink is used to print or print the pattern of the second electrode 40, the pattern of the second electrode 40 includes the pattern of the contact area 40A and the pattern of the working area 40B.

[0041] Specifically, in the two-electrode implantable sensor, the first electrode 20 can be a working electrode, and the second electrode 40 can be a counter electrode, or the first electrode 20 can be a counter electrode, and the second electrode 40 can be a working electrode, so that in steps S1 and S3, the conductive ink is selected according to the properties of the specific electrode.

[0042] In steps S2 and S3, the curing method can be thermal curing, photocuring, radiation curing, etc. Specifically, when thermal curing is used, the temperature is preferably 80-200℃, and the time is preferably 10-200 minutes. When photocuring is used, ultraviolet photocuring is preferred.

[0043] In the preparation of the substrate 30, since the first through hole 301 penetrating the substrate 30 is reserved, the first electrode 20 and the second electrode 40 of the implantable sensor can be connected to the connector on the same surface through the first through hole 301, without the need to cut the substrate 30. Not only can the consistency and yield be effectively improved, but also the process can be effectively simplified, the cost can be reduced, and the large-scale production can be easily realized. In addition, compared with the method of printing electrodes on both surfaces of the substrate, the preparation method of the present application does not need to manually or by equipment to turn over the substrate, which reduces the requirements of the equipment, and the electrode patterning is flexible and the alignment is more accurate.

[0044] Optionally, when printing or printing the pattern of the substrate 30, the first through hole 301 can be reserved at the contact area 20A of the first electrode 20, and then the second electrode 40 is prepared on the substrate 30, so that the first electrode 20 and the second electrode 40 can be connected with the connector on the surface where the second electrode 40 is located.

[0045] At this time, the first through hole 301 can be further filled with conductive ink, which can improve the connection stability of the first electrode 20 and the connector.

[0046] Optionally, when printing or printing the pattern of the substrate 30, the pattern of the substrate 30 completely covers the pattern of the first electrode 20, and the first through hole 301 is reserved at any position, and the position where the first through hole 301 is located is used as the contact area 40A of the second electrode 40, and then the second conductive ink is printed or printed, and the second conductive ink is filled into the first through hole 301. After the second conductive ink in the first through hole 301 is solidified, it becomes the contact area 40A of the second electrode 40, so that the first electrode 20 and the second electrode 40 can be connected with the connector on the surface where the first electrode 20 is located.

[0047] In order to ensure the flexibility of the implantable sensor of the present application, the thickness of the substrate 30 is preferably 20-500 μm, further preferably 50-300 μm, and more preferably 150-250 μm. In order to ensure the connection effect of the first electrode 20 or the second electrode 40 with the connector through the first through hole 301, the diameter of the first through hole 301 is 20-1500 μm.

[0048] As shown in FIG. 1, the implantable sensor provided by the present application is a two-electrode implantable sensor. Figure 3 As shown in FIG. 2, the implantable sensor provided by another embodiment of the present application is a three-electrode implantable sensor, which is different from the two-electrode implantable sensor in that it further includes an insulating layer 50 and a third electrode 60 which are sequentially covered on the second electrode 40.

[0049] Therefore, during preparation, before peeling off the substrate, it further includes:

[0050] The pattern of the insulating layer 50 is printed or printed on the second electrode 40 by using insulating paste, and the second through hole penetrating the insulating layer 50 is reserved, and then solidified;

[0051] The pattern of the third electrode 60 is printed or printed on the insulating layer 50 by using the third conductive ink, and then solidified, and the three-electrode implantable sensor is obtained after peeling off the substrate. The first electrode 20, the second electrode 40 and the third electrode 60 of the implantable sensor can be connected with the connector on the same surface through the first through hole 301 and the second through hole.

[0052] The insulating paste is selected from a thermosetting insulating paste or a ultraviolet curing insulating paste, the third electrode 60 is generally a reference electrode, and the third conductive ink is preferably a silver / silver chloride paste.

[0053] Optionally, the curing method of the insulating paste and the third conductive ink can also be thermal curing, light curing, radiation curing, etc. Specifically, when thermal curing is adopted, the temperature is preferably 80-200°C, and the time is preferably 10-200 minutes. When light curing is adopted, ultraviolet light curing is preferred.

[0054] It can be understood that the first electrode 20, the second electrode 40 and the third electrode 60 of the three-electrode implantable sensor can be connected with the connector on the surface where the first electrode 20 is located, or can be connected with the connector on the surface where the third electrode 60 is located.

[0055] Optionally, when the pattern of the substrate 30 is printed or printed, the position of the first through hole 301 can be reserved at the contact area 20A of the first electrode 20, and then the second electrode 40 is prepared on the substrate 30. When the pattern of the insulating layer 50 is printed or printed, two second through holes penetrating the insulating layer 50 are reserved, one overlaps the position of the first through hole 301, and the other is reserved at the contact area 40A of the second electrode 40. In this way, the first electrode 20, the second electrode 40 and the third electrode 60 can be connected with the connector on the surface where the third electrode 60 is located.

[0056] At this time, the first through hole 301 and the second through hole can be further filled with conductive ink, which can improve the connection stability of the first electrode 20, the second electrode 40 and the connector.

[0057] Optionally, when the pattern of the substrate 30 is printed or printed, the pattern of the substrate 30 completely covers the pattern of the first electrode 20, and two first through holes 301 are reserved at any position, one of which is located at the contact area 40A of the second electrode 40. Then, when the second conductive ink is printed or printed, the second conductive ink is filled into the first through hole 301, and after the second conductive ink in the first through hole 301 is cured, the contact area 40A of the second electrode 40 is obtained. Then, when the pattern of the insulating layer 50 is printed or printed, a second through hole is reserved at the position of the other first through hole 301, and then when the third conductive ink is printed or printed, the third conductive ink is filled into the first through hole 301 and the second through hole. After the third conductive ink in the first through hole 301 and the second through hole is cured, the contact area of the third electrode 60 is obtained. In this way, the first electrode 20, the second electrode 40 and the third electrode 60 can be connected with the connector on the surface where the first electrode 20 is located.

[0058] Optionally, the first through hole 301 penetrating the substrate 30 and the second through hole penetrating the insulating layer 50 are in the shape of a circle, a rectangle, a triangle, a pentagon, a hexagon, etc. Preferably, the first through hole 301 and the second through hole are in the same shape and have the same size.

[0059] Hereinafter, the preparation method of the implantable sensor will be further described through the following specific examples.

[0060] Example 1

[0061] The polytetrafluoroethylene substrate was cleaned with ethanol and then dried with nitrogen. Then, the first platinum-carbon paste was patterned and printed on the polytetrafluoroethylene substrate using an automatic screen printing machine. The working area and the contact area of the first platinum-carbon electrode were printed, and dried at room temperature for 10 minutes. Then, liquid polyimide was printed thereon, and the first through hole was reserved in the contact area of the first platinum-carbon electrode. Then, it was placed on a heating table and cured at 200°C for 30 minutes to obtain the first platinum-carbon electrode and the polyimide substrate covering the first platinum-carbon electrode. The polyimide substrate had the first through hole in the contact area of the first platinum-carbon electrode.

[0062] Then, the second platinum-carbon paste was printed on the polyimide substrate, and then cured in a 130°C oven for 15 minutes to obtain the second platinum-carbon electrode. Then, the ultraviolet curing insulating paste was printed on the second platinum-carbon electrode, and the second through hole was reserved in the contact area of the second platinum-carbon electrode and the first through hole area of the substrate, respectively. Then, it was cured under ultraviolet light for 15 minutes to obtain the insulating layer. Then, the silver / silver chloride paste was printed on the insulating layer, and cured in a 130°C oven for 15 minutes to obtain the reference electrode. Finally, the polytetrafluoroethylene substrate was peeled off to obtain the implantable sensor.

[0063] Example 2

[0064] The polytetrafluoroethylene substrate was cleaned with ethanol and then dried with nitrogen. Then, the first platinum-carbon paste was patterned and printed on the polytetrafluoroethylene substrate using an automatic inkjet printing device. The working area and the contact area of the first platinum-carbon electrode were printed, and dried at room temperature for 10 minutes. Then, liquid polyimide was printed thereon, and the first through hole was reserved in the contact area of the first platinum-carbon electrode. Then, it was placed on a heating table and cured at 200°C for 30 minutes to obtain the first platinum-carbon electrode and the polyimide substrate covering the first platinum-carbon electrode. The polyimide substrate had the first through hole in the contact area of the first platinum-carbon electrode.

[0065] Then a second platinum carbon paste is printed on the polyimide substrate and fills the through hole, and then oven cured at 130°C for 15 min to obtain a second platinum carbon electrode. Then an ultraviolet cured insulation paste is printed on the working area of the second platinum carbon electrode, and a second through hole is reserved through the contact area of the second platinum carbon electrode and the first through hole area of the substrate respectively, and then cured under ultraviolet light for 15 min to obtain an insulation layer. Then a silver / silver chloride paste is printed on the insulation layer and oven cured at 130°C for 15 min to obtain a reference electrode. Finally, the polytetrafluoroethylene substrate is peeled off to obtain an implantable sensor.

[0066] Example 3

[0067] The silicon substrate is cleaned with acetone and then dried with nitrogen, followed by spin coating photoresist and baking as a sacrificial layer. Then, the carbon paste is patterned and printed on the photoresist layer using an automatic screen printing machine, and the working area and contact area of the first carbon electrode are printed and dried at room temperature for 10 minutes. Then, liquid polyethylene terephthalate is printed thereon, and a first through hole is reserved through the contact area of the first carbon electrode, and then placed on a heating table and cured at 200°C for 30 min to obtain a first carbon electrode and a polyethylene terephthalate substrate covering the first carbon electrode, and the polyethylene terephthalate substrate has a first through hole in the contact area of the first carbon electrode.

[0068] Then a platinum carbon paste is printed on the polyethylene terephthalate substrate and fills the through hole, and then oven cured at 130°C for 15 min to obtain a platinum carbon electrode. Then an ultraviolet cured insulation paste is printed on the working area of the platinum carbon electrode, and a second through hole is reserved through the contact area of the second platinum carbon electrode and the first through hole area of the substrate respectively, and then cured under ultraviolet light for 15 min to obtain an insulation layer. Then a silver / silver chloride paste is printed on the insulation layer and oven cured at 130°C for 15 min to obtain a reference electrode. Finally, the photoresist layer is removed by wet etching to obtain an implantable sensor.

[0069] Example 4

[0070] The glass substrate is cleaned with acetone and then dried with nitrogen, followed by spin coating photoresist and baking as a sacrificial layer. Then, the platinum carbon paste is patterned and printed on the photoresist layer using an automatic inkjet printing device, and the working area and contact area of the first platinum carbon electrode are printed and dried at room temperature for 10 minutes. Then, liquid polycarbonate is printed thereon, and a first through hole is reserved through the contact area of the first platinum carbon electrode, and then placed on a heating table and cured at 200°C for 30 min to obtain a first platinum carbon electrode and a polycarbonate substrate covering the first platinum carbon electrode, and the polycarbonate substrate has a first through hole in the contact area of the first platinum carbon electrode.

[0071] Then, the carbon paste is printed on the polycarbonate substrate, and the carbon paste fills the through hole, and then the carbon electrode is obtained by oven curing at 130℃ for 15min. Then, the ultraviolet curing insulation paste is printed on the working area of the carbon electrode, and the second through hole is reserved through the contact area of the second platinum carbon electrode and the first through hole area of the substrate respectively, and then the insulation layer is obtained by curing under ultraviolet light for 15min. Then, the silver / silver chloride paste is printed on the insulation layer, and the reference electrode is obtained by oven curing at 130℃ for 15min. Finally, the photoresist layer is removed by wet etching to obtain the implantable sensor.

[0072] The technical features of the above-described embodiments can be combined in any manner. In order to make the description simple, all possible combinations of the technical features in the above-described embodiments are not described, but as long as the combinations of the technical features do not contradict, they should be considered as falling within the scope of the present disclosure.

[0073] The above-described embodiments only express several implementation manners of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation on the scope of the patent. It should be pointed out that for those skilled in the art, some modifications and improvements can be made without departing from the concept of the present application, and these all fall within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A method of making an implantable sensor, comprising: The preparation method comprises the following steps: printing or printing a pattern of a first electrode on a substrate by using a first conductive ink; printing or printing a pattern of a base on the pattern of the first electrode by using a liquid polymer, and reserving a first through hole penetrating the base, and then curing; printing or printing a pattern of a second electrode on the base by using a second conductive ink, and then curing; peeling off the substrate to obtain a two-electrode implantable sensor, the first electrode and the second electrode of the implantable sensor can be connected with a connector on the same surface through the first through hole, wherein the curing is thermal curing, light curing or radiation curing.

2. The method of claim 1, wherein the implantable sensor is prepared by, The temperature of the thermal curing is 80-200℃.

3. The method of claim 2, wherein the implantable sensor is prepared by, The time of the thermal curing is 10-200 minutes.

4. The method of claim 1, wherein the implantable sensor is prepared by, The light curing is specifically ultraviolet light curing.

5. The method of claim 1, wherein the implantable sensor is prepared by, The first through hole is reserved in a contact area of the first electrode.

6. The method of claim 1, wherein the implantable sensor is prepared by, The first through hole and the second through hole have the same shape.

7. The method of claim 1, wherein the implantable sensor is prepared by, When the first electrode is a working electrode, the second electrode is a counter electrode; when the first electrode is a counter electrode, the second electrode is a working electrode.

8. The method of claim 1-7, wherein, Before peeling off the substrate, further comprising: printing or printing a pattern of an insulating layer on the second electrode by using an insulating paste, and reserving a second through hole penetrating the insulating layer, and then curing; printing or printing a pattern of a third electrode on the insulating layer by using a third conductive ink, and then curing, to obtain a three-electrode implantable sensor after peeling off the substrate; The number of the first through hole is one or two.

9. The method of claim 8, wherein: When the number of the first through hole is one, the first through hole is reserved in a contact area of the first electrode; the number of the second through hole is two, one of the second through holes is located at the same position as the first through hole, and the other second through hole is reserved in a contact area of the second electrode.

10. The method of claim 8, wherein: When the number of the first through hole is two, the second conductive ink fills one of the first through holes, and the second through hole is reserved at the other first through hole, so that the third conductive ink fills the second through hole and the other first through hole.

Images