Analyte sensor device and preparation method thereof

Abstract

The invention relates to an analyte sensor device and a preparation method thereof, and belongs to the technical field of biological information detection sensors. In the preparation method of the analyte sensor device provided by the invention, the analyte sensor device comprises a printed circuit board, a sensor and an electrode plate, and the method comprises the following steps: coating a carbon fiber layer on a preset welding spot of the sensor; one end of an electrode plate is fixed to the printed circuit board through a patch, and the other end of the electrode plate is in lap joint with a preset welding spot of the sensor; and coating the welding flux at the lap joint of the electrode plate and the sensor for laser welding to finish the preparation of the analyte sensor device. Wherein the sensor and the electrode plate are welded through the preset welding spot so as to be connected with the printed circuit board, and the carbon fiber layer is arranged on the preset welding spot, so that good contact and conductivity are ensured, heat conduction to the sensor during welding can be reduced, and the sensor is prevented from being damaged; the prepared sensor product has the advantages of low noise and high connection stability.

Description

Technical Field

[0001] The present application relates to an analyte sensor device and a preparation method thereof, belonging to the technical field of biological information detection sensors. Background Art

[0002] Diabetes is one of the common chronic diseases that seriously threatens human health. The detection and / or monitoring of analyte levels (such as glucose, ketones, lactate, oxygen, hemoglobin AIC, etc.) is extremely important for the health of individuals with diabetes. In particular, real-time monitoring of blood glucose helps patients and doctors evaluate their condition, develop reasonable and scientific treatment plans, or adjust existing plans. Therefore, glucose sensors are also the most studied and earliest commercialized biosensors in the field of biosensors.

[0003] In the prior art, sensors are mostly fixed and connected by plugging. Specifically, the printed circuit board is fixed by a shell, and a sensor positioning groove is further provided to fix the sensor, and an elastic spring sheet in contact with the sensor is provided. In this way, the sensor can be connected to the printed circuit board through the elastic spring sheet. However, this plug-in physical contact connection has the problems of relatively high sensor noise and poor connection stability. Summary of the invention

[0004] In order to solve the above problems, an analyte sensor device and a preparation method thereof are provided. The preparation method of the analyte sensor device in the present application scheme, wherein the sensor and the electrode sheet are welded to the printed circuit board through preset solder joints, which can avoid the problem of blind insertion and damage to the sensor during installation caused by mechanical connection, and further a carbon fiber layer is provided on the preset solder joints, while ensuring good contact and conductivity, and reducing heat conduction to the sensor during welding, thereby avoiding damage to the analyte sensor device. The prepared sensor product has the advantages of low noise and high connection stability.

[0005] The present application provides a method for preparing an analyte sensor device, wherein the analyte sensor device comprises a printed circuit board, a sensor, and an electrode sheet, and the method comprises:

[0006] Covering the preset welding points of the sensor with a carbon fiber layer;

[0007] Fix one end of the electrode sheet to the printed circuit board through a patch, and overlap the other end of the electrode sheet with a preset soldering point of the sensor;

[0008] Solder is coated on the overlap between the electrode sheet and the sensor for laser welding to complete the preparation of the analyte sensor device.

[0009] In the present application, laser welding is used to connect the sensor to the electrode sheet, thereby realizing the connection between the sensor and the printed circuit board, which can greatly reduce the size of the sensor and provide more possibilities for realizing smaller and lighter product designs. In addition, the use of laser welding for processing can use more abundant and accurate methods for detecting contact reliability, such as CCD visual detection, multimeter detection, etc., to ensure the normal use of the analyte sensor device.

[0010] Optionally, the laser welding time is 0.5s to 1s, and the welding temperature is 140°C to 150°C. If the welding time is less than 0.5s, or the temperature is less than 140°C, the solder paste will not be fully melted, which may easily lead to cold solder joints. If the welding time is more than 1s, or the temperature is higher than 150°C, it may cause excessive heat accumulation and damage the sensor.

[0011] It should be noted that those skilled in the art can control the laser welding time within an appropriate range by adjusting the appropriate laser welding power or controlling the use of a laser with a small core diameter, or reducing the spot size by selecting a collimating focusing head to concentrate the energy on one point, or using a front and back dual-beam laser method, or using an annular spot, multi-wavelength fiber-semiconductor composite welding and other methods to increase the welding speed.

[0012] Optionally, the solder is a lead-free solder paste having a melting point lower than 138° C., which can reduce the instantaneous temperature during laser welding and avoid damage to the sensor due to the high temperature generated during welding.

[0013] Optionally, the resin matrix is ​​selected from one or more of bismaleimide resin or polyethylene resin; and / or,

[0014] The carbon filament fibers are selected from one or more of polyacrylonitrile carbon fibers and pitch-based carbon fibers.

[0015] Bismaleimide resin has excellent heat resistance, wave transmission, radiation resistance, flame retardancy, good mechanical properties and dimensional stability, polyethylene resin has excellent heat resistance and chemical stability, and bismaleimide resin and polyethylene resin are two resin matrices that are widely used and have relatively mature preparation processes, while polypropylene or epoxy resin matrices have poor high temperature resistance and poor effect of blocking heat conduction in high temperature welding processes. Those skilled in the art can also select other rubber matrices or other non-rubber elastomer materials with better heat blocking properties according to the need to block heat.

[0016] Polyacrylonitrile carbon fiber and bismaleimide resin have good compatibility and adhesion, can form a stable composite material structure, the production process is relatively mature, the output is large, and can meet the needs of large-scale industrial production; asphalt-based carbon fiber and polyethylene resin have good compatibility and adhesion, can form a composite material with excellent performance, asphalt-based raw materials are easy to obtain, low cost, and the price advantage is obvious. For example, other types of carbon fibers such as viscose-based carbon fibers are lower than polyacrylonitrile carbon fibers and asphalt-based carbon fibers in mechanical properties and thermal properties, cannot meet the requirements, and the raw material cost is higher, the process is complex and unstable, and is not suitable for mass production. Those skilled in the art can also select other carbon fiber materials based on mechanical properties and thermal properties. The above-mentioned two carbon fiber properties meet the requirements, and have obvious advantages in cost and manufacturing process. Other carbon fibers that meet the requirements can also achieve the technical effects of this application.

[0017] Optionally, the thickness of the carbon fiber layer is 0.1-0.3 mm; and / or,

[0018] The electrical conductivity of the carbon filament fiber is not less than 2 kS / m.

[0019] If the carbon fiber layer is too thick, the resistance fluctuation will increase, the conductivity will decrease, the manufacturing difficulty will increase, and the cost will increase due to the increased process complexity. If the carbon fiber layer is too thin, the thermal insulation function of the carbon fiber layer will decrease, and there is a possibility of damage to the sensor. At the same time, a too thin carbon fiber layer may also reduce the contact points between the carbon filaments, thereby reducing its conductive performance.

[0020] Optionally, the electrode sheet is a chromium-zirconium-copper electrode;

[0021] Optionally, the electrical conductivity of the electrode sheet is not less than 43MS / m, and the thermal conductivity is 135-165W / (m·K).

[0022] The chromium-zirconium-copper electrode sheet has excellent electrical and thermal conductivity, can meet the needs of high-efficiency transmission and rapid heat dissipation, has high hardness and wear resistance, can withstand wear and impact during welding, and prolongs service life. It is suitable for laser welding and electrical signal transmission.

[0023] The electrical conductivity is not less than 43MS / m, which can effectively ensure that the electrode sheet transmits current efficiently and reduces current loss. If it is lower than this range, the welding effect may not be effectively monitored after welding, and the electrical signal cannot be effectively transmitted to the receiving end. The thermal conductivity is within the range of 135-165W / (m·K) to ensure that the energy generated during the welding process can be quickly dissipated. If it is higher than 165W / (m·K), the preparation process of the electrode sheet is too high, which is not conducive to realization and cost control. If it is lower than 135W / (m·K), the heat dissipation performance is insufficient, which may cause the sensor to be damaged by heat.

[0024] Optionally, the contact area between the electrode sheet and the sensor is 0.5 to 1.0 mm 2 , controlling the contact area between the electrode sheet and the sensor can reduce the welding area as much as possible, thereby shortening the welding time and avoiding damage to the sensor caused by high temperature generated during welding.

[0025] Optionally, after deducting the contact area between the electrode sheet and the patch on the printed circuit board and the contact area between the electrode sheet and the sensor, the remaining electrode sheet area is 1.5 to 5 mm 2 Increasing the remaining area of ​​the electrode sheet at the welding point as much as possible can increase the heat dissipation effect, accelerate the cooling, thereby reducing the amount of heat conduction to the sensor and avoiding damage to the sensor caused by the high temperature generated during welding.

[0026] Optionally, the number of the electrode sheets is multiple, and the sensor is provided with multiple preset welding points equal to the number of the electrode sheets. Those skilled in the art can set the corresponding number of preset welding points and the number of electrode sheets matched with the preset welding points according to the specific situation of the sensor.

[0027] The present application also provides an analyte sensor device, comprising:

[0028] A printed circuit board, wherein a patch is provided on the printed circuit board;

[0029] A sensor, wherein the sensor comprises a preset welding point, an upper layer of the preset welding point is provided with a carbon fiber layer, and the carbon fiber layer comprises a resin matrix and carbon filament fibers inside;

[0030] An electrode sheet, one end of which is welded to a preset welding point of the sensor, and the other end of which is connected to the patch.

[0031] In the analyte sensor device, the sensor and the electrode sheet are welded through preset welding points, and then connected to the printed circuit board through the electrode sheet. Compared with the connection method of the sensor through contact spring plugging in the prior art, it has lower sensor noise and higher connection stability, and the sensor is not easily damaged due to blind plugging during installation.

[0032] The beneficial effects of this application include but are not limited to:

[0033] The preparation method of the analyte sensor device in the scheme of the present application, wherein the sensor and the electrode sheet are welded to the printed circuit board through preset solder joints. Compared with the connection method of the sensor in the prior art by plugging in the contact spring, it can avoid the problem of blind plugging and damaging the sensor during installation due to mechanical connection, and the use of laser welding can improve the yield rate in the processing technology, and can greatly reduce the size of the device to meet the needs of smaller and lighter products; in addition, a carbon fiber layer is provided on the upper layer of the preset solder joints, wherein the resin matrix in the carbon fiber layer can reduce heat conduction to the sensor, and the carbon filament fiber therein can ensure good conductivity between the electrode sheet and the preset solder joints of the sensor, while ensuring good contact and conductivity while reducing heat conduction, avoiding damage to the analyte sensor device, the sensor product prepared by this method has the advantages of low noise and high connection stability, and has smaller current loss and higher current performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0035] Figure 1 A top view of an analyte sensor device according to an embodiment of the present application;

[0036] Figure 2 A three-dimensional diagram of an analyte sensor device according to an embodiment of the present application;

[0037] Figure 3 This is a schematic diagram of the working process of the analyte sensor device involved in the embodiment of the present application;

[0038] Figure 4 A top view of an electrode sheet in an analyte sensor device according to an embodiment of the present application;

[0039] Figure 5 A side view of a carbon fiber layer in an analyte sensor device according to an embodiment of the present application;

[0040] Figure 6 Schematic diagram of the arrangement of carbon filament fibers in the analyte sensor device according to an embodiment of the present application.

[0041] List of drawings and reference numerals:

[0042] 1-printed circuit board, 2-electrode sheet, 3-sensor, 4-carbon fiber layer, 5-resin matrix, 6-carbon filament fiber. DETAILED DESCRIPTION

[0043] The present application is described in detail below in conjunction with examples, but the present application is not limited to these examples. Unless otherwise specified, the raw materials and reagents in the examples of the present application are purchased through commercial channels.

[0044] like Figures 1 to 6 As shown, the embodiment of the present application provides an analyte sensor device, including: a printed circuit board, on which a patch is arranged; a sensor, which includes a preset solder joint, and a carbon fiber layer is arranged on the upper layer of the preset solder joint, and the carbon fiber layer includes a resin matrix and carbon filament fibers inside; an electrode sheet, one end of the electrode sheet is welded to the preset solder joint of the sensor, and the other end is connected to the patch. Figure 5 As shown, the sensor welding part pastes a carbon fiber layer composed of carbon filament fibers and resin matrix on the upper layer of the original silk-screen electrode, which can effectively conduct electrical signals while reducing the heat generated by the laser welding process and preventing the bioenzyme activity of the sensor from being denatured due to the welding temperature.

[0045] As a feasible implementation manner, the resin matrix is ​​selected from one or more of bismaleimide resin or polyethylene resin; the carbon filament fiber is selected from one or more of polyacrylonitrile carbon fiber or asphalt-based carbon fiber.

[0046] Those skilled in the art can adjust the arrangement of the carbon filament fibers as needed. For example, in a specific embodiment, two layers of carbon filament fibers are provided, and the spacing between the carbon filament fibers in each layer can also be set as needed, such as Figure 6 As shown, the figure highlights the layered arrangement of the carbon filament fibers and the rubber matrix. In fact, the rubber matrix completely wraps the two layers of carbon filament fibers. For example, in a specific embodiment, the spacing is 0.340 to 0.342 nm. The angle of the carbon filament fibers can also be set as needed. For example, in a specific embodiment, Figure 6 As shown, the carbon filament fibers are arranged crosswise at 45° / -45°. The 45° / -45° crosswise arrangement can effectively increase the structural strength of the carbon fiber material, evenly distribute the force, thereby reducing stress concentration, and is not easily deformed during welding and use.

[0047] As a feasible implementation, the thickness of the carbon fiber layer is 0.1-0.3 mm; and the electrical conductivity of the carbon filament fiber is not less than 2 kS / m.

[0048] As a feasible implementation method, the electrode sheet is a chromium-zirconium-copper electrode, the electrical conductivity of the electrode sheet is not less than 43MS / m, and the thermal conductivity is 135-165W / (m·K).

[0049] As a feasible implementation method, the contact area between the electrode sheet and the sensor is 0.5 to 1.0 mm 2 .

[0050] As a feasible implementation method, after subtracting the contact area between the electrode sheet and the patch on the printed circuit board and the contact area between the electrode sheet and the sensor, the remaining electrode sheet area is 1.5 to 5 mm 2 .

[0051] As a feasible implementation method, the number of electrode sheets is multiple, and the sensor is provided with multiple preset welding points equal to the number of electrode sheets. As a specific implementation method, Figure 4 As shown, there are three electrode sheets and three preset welding points on the sensor.

[0052] like Figure 3 As shown, the sensor is mainly used to collect analyte data, for example, the analyte sensor here is used to collect glucose data, the electrode sheet is used to connect the printed circuit board and the sensor, and other circuit components are arranged on the printed circuit board to complete data collection and transmission, such as sending digital signals to the receiving end. This is well known to those skilled in the art, so it is not described in detail in this application.

[0053] In a specific embodiment, the electrode sheet is connected to the PCBA through a patch, and is connected to the AFE chip of the PCBA through the PCBA patch wire. The extended part of the electrode sheet overlaps the three contacts of the sensor. The laser welding machine applies solder to the overlapping position, melts the solder through a high-energy-density laser beam, and establishes a connection between the screen-printed electrode of the sensor and the AFE chip of the PCBA. The electrical signal generated by the chemical reaction between glucose and a specific enzyme in the sensor is transmitted to the PCBA through the electrode sheet, and is converted into a digital signal by the internal chip of the PCBA and uploaded to realize the data collection and transmission functions.

[0054] The present invention provides a method for preparing an analyte sensor device, the method comprising the following steps:

[0055] Covering the preset welding points of the sensor with a carbon fiber layer;

[0056] Fix one end of the electrode sheet to the printed circuit board through a patch;

[0057] Lap the other end of the electrode sheet with the preset welding point of the sensor;

[0058] Solder is coated on the overlap between the electrode sheet and the sensor for laser welding to complete the preparation of the analyte sensor device.

[0059] As a feasible implementation method, the laser welding time is 0.5s to 1s, and the welding temperature is 140°C to 150°C.

[0060] As a feasible implementation method, the solder is lead-free solder paste, and the melting point of the lead-free solder paste is lower than 138°C.

[0061] In a specific embodiment, the welding step of laser welding the sensor and the circuit board includes:

[0062] A) The electrode sheet is mounted on the PCB substrate by SMT patch method;

[0063] B) The sensor is assembled into the bearing base;

[0064] C) Install the PCBA with the electrode sheet mounted on it into the base;

[0065] D) The PCBA electrode sheet is overlapped on the preset soldering point of the sensor;

[0066] E) Place the electrode in a laser welding machine, and apply solder paste to the connection between the electrode and the sensor;

[0067] F) The laser welding machine emits a high-density laser beam to the joint, melting the solder paste to form a solder joint that wraps around the electrode sheet joint;

[0068] G) After melting, the solder joint status is inspected by visual inspection CCD image. The solder joint should be full, bright, without cracks and pores.

[0069] Among them, in step E), the solder paste is preferably lead-free solder paste, for example, a specific material is Sn42Bi57.6Ag0.4, and the melting point is 137°C. It has a good positive effect on the conductivity of the solder joint and improves the brittleness of the solder joint, and only requires a lower temperature to achieve solidification; in step F), the welding time is controlled to 800ms and the temperature is controlled to 145°C. Through the heat insulation function of the carbon fiber material, the adverse effects of high temperature on the sensor performance can be reduced.

[0070] In order for the carbon fiber layer to play a better role, the embodiment of the present application has requirements for the performance of the carbon fiber layer, requiring that the sensitivity change Δcv before and after the test sensor welding operation should be ≤7%, and the conductivity of the patch electrode sheet and the sensor side measured by the conductivity meter should be ≥43MS / m. It should be noted that the purpose of the above performance requirements is only to screen better carbon fiber layers with better performance, and it is not a necessary condition. The specific test steps include: placing the sensor in glucose solutions of different concentrations, testing its current in different glucose solutions through a current receiving device, calculating the linearity, i.e., cv, and testing under the same conditions after processing to calculate the changes before and after. Preheat the conductivity meter and calibrate it, paste the conductivity meter test electrodes on the electrode sheet and the sensor side respectively, and record the conductivity after the instrument readings are stable. Repeat the measurement three times to take the average value. The test in which the carbon fiber layer matrix and the carbon filament fiber are empty indicates that the device structure does not contain a carbon fiber layer. The test results are shown in Table 1.

[0071] Table 1 Test results of carbon fiber layer material selection

[0072]

[0073]

[0074] According to the results in Table 1, the selection of the carbon fiber layer material of the present application scheme has good sensitivity change and conductivity performance. When the matrix is ​​a carbon fiber layer matrix or a polyethylene resin, and the carbon filament fiber is an asphalt-based carbon fiber or a polyacrylonitrile carbon fiber, the sensor performance is less affected, and the conductivity meets the requirements.

[0075] The setting of the carbon fiber layer is more critical. If the carbon fiber layer is not set, the sensor is easily damaged by heat after processing, and the enzyme layer is destroyed, resulting in the inability to carry out biochemical reactions and read current. In addition, the material selection of the carbon fiber layer in this application also has obvious advantages. When other matrix and carbon filament fibers are selected, the sensitivity of the sensor is significantly reduced after processing.

[0076] The present application has conducted extensive experiments on product parameters and control conditions in the preparation method to screen suitable operating conditions, especially focusing on the impact on the protection performance of sensor products. Some of the data are shown in Tables 2 and 3 below. The parameters and preparation of each sample in Table 2 are basically the same as the structure and preparation process in Examples 1 and 2, and the differences have been explained in Table 2.

[0077] Table 2 Sensor device parameters and effect test of preparation process

[0078]

[0079]

[0080] Table 2 continued

[0081]

[0082] Table 3 Sample test results

[0083] serial number Is the sensor damaged? ConductivityMS / m Solder joint cold welding Sample 1 no 52.3 No cold solder joints Sample 2 no 49.5 No cold solder joints Sample 3 yes / No cold solder joints Sample 4 no 25.9 Solder joints Sample 5 yes / No cold solder joints Sample 6 yes / No cold solder joints Sample 7 yes / No cold solder joints

[0084] According to the results in Table 2 and Table 3, if the thickness of the carbon fiber layer is too small, the sensor is easily damaged after processing, and if the thickness is too large, the conductivity will decrease after processing and a cold weld will occur. 2 Insufficient heat dissipation can easily cause damage to the sensor. In addition, when the welding temperature is higher than 150°C, there is also the problem that the temperature is too high and the sensor is easily damaged. In addition, the melting point of the solder paste is also important. When a solder paste with a melting point of 183°C is selected, the welding temperature needs to reach 200°C. At this time, the temperature is too high and the sensor is damaged.

[0085] The above is only the embodiment of the present application, and the protection scope of the present application is not limited by these specific embodiments, but is determined by the claims of the present application. For those skilled in the art, the present application can have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the technical ideas and principles of the present application should be included in the protection scope of the present application.

Claims

1. A method for preparing an analyte sensor device, characterized in that: The analyte sensor device comprises a printed circuit board, a sensor and an electrode sheet, and the method comprises: Covering the preset welding points of the sensor with a carbon fiber layer, wherein the carbon fiber layer includes a resin matrix and carbon filament fibers inside; Fix one end of the electrode sheet to the printed circuit board through a patch, and overlap the other end of the electrode sheet with a preset soldering point of the sensor; Solder is coated on the overlap between the electrode sheet and the sensor for laser welding to complete the preparation of the analyte sensor device.

2. The method for preparing the analyte sensor device according to claim 1, characterized in that: The laser welding time is 0.5s-1s, and the welding temperature is 140°C-150°C.

3. The method for preparing the analyte sensor device according to claim 1, characterized in that: The solder is lead-free solder paste, and the melting point of the lead-free solder paste is lower than 138°C.

4. The method for preparing the analyte sensor device according to claim 1, characterized in that: The resin matrix is ​​selected from one or more of bismaleimide resin and polyethylene resin; and / or, The carbon filament fibers are selected from one or more of polyacrylonitrile carbon fibers and pitch-based carbon fibers.

5. The method for preparing the analyte sensor device according to claim 4, characterized in that: The thickness of the carbon fiber layer is 0.1 to 0.3 mm; and / or, The electrical conductivity of the carbon filament fiber is not less than 2 kS / m.

6. The method for preparing the analyte sensor device according to claim 1, characterized in that: The electrode sheet is a chromium-zirconium-copper electrode; Optionally, the electrical conductivity of the electrode sheet is not less than 43MS / m, and the thermal conductivity is 135-165W / (m·K).

7. The method for preparing the analyte sensor device according to claim 1, characterized in that: The contact area between the electrode sheet and the sensor is 0.5-1.0 mm 2 .

8. The method for preparing an analyte sensor device according to claim 1, characterized in that: The area of ​​the electrode sheet minus the contact area between the electrode sheet and the patch on the printed circuit board and the contact area between the electrode sheet and the sensor is 1.5 to 5 mm 2 .

9. The method for preparing the analyte sensor device according to claim 1, characterized in that: The number of the electrode sheets is multiple, and the sensor is provided with multiple preset welding points equal to the number of the electrode sheets.

10. An analyte sensor device, characterized in that include: A printed circuit board, wherein a patch is provided on the printed circuit board; A sensor, wherein the sensor comprises a preset welding point, an upper layer of the preset welding point is provided with a carbon fiber layer, and the carbon fiber layer comprises a resin matrix and carbon filament fibers inside; An electrode sheet, one end of which is welded to a preset welding point of the sensor, and the other end of which is connected to the patch.

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