TWM252016U - Auto-sampling electrochemical sensing strips with screen-printed three electrodes - Google Patents

Description

M252016 新型 Description of the new type: [Technical field to which the new type belongs] This creation is about a disposable three-electrode electrochemical test strip, especially a disposable siphon-printed three-electrode electrochemical quantitative detection ancient-style sheet, in which the liquid Must contact the electrode area, and the droplets are sucked into the electrode area through the siphon effect on the substrate. [Previous technology] In traditional electrochemical measurement, the three-electrode system is mainly composed of a working electrode, a reference electrode, and a counter electrode, and is used for analysis and detection with a common three-electrode electrochemical potentiostat. In commonly used detection systems, the working electrode material can be composed of gold, platinum, glassy carbon, mercury, graphite and other materials; the reference electrode is mainly composed of saturated calomel electrode, silver / vaporized silver electrode; dual The electrodes are mostly platinum electrodes. In the application of potential, the potential applied to the working electrode is the working potential used relative to the potential of the reference electrode; the dual electrode is mainly designed to match the applied potential of the working electrode; the reference electrode itself provides a constant potential. Will cause potential changes as the reaction current increases or decreases. Different from the two-electrode electrochemical system, the addition of the reference electrode to the three-electrode system can not only effectively compensate the potential drop caused by the internal resistance, but also prevent the applied working potential from shifting and floating, making the detection accurate. Sex is greatly improved. In terms of the development of electrochemical sensors, the volume of commercial electrodes is not as good as micro-daggers. Moreover, due to the problem of handover and pollution caused by medical testing, the cost of testing with commercial electrodes is high, and The required volume of the biometric M252016 body is large, “can not reach the end of the 3 stains” orphan type detection method, so the development of disposable electrodes in the form of test strips can better meet the actual needs, and cooperate with the semiconductor industry mature printing technology The preparation of the electrode reduces the production cost and can effectively increase the yield. The preparation of the disposable electrode is more economical than the commonly used electrochemical three-electrode system. In line with future inspection trends. “Printed electrode” is exactly what the name implies, that is, it is matched with printing technology to print the electrode system directly on the test piece to facilitate a large number of processes and reduce costs. From the earliest invention, printing was limited to the portion of the Weizuo electrode, which would be conductive Carbon, gold, silver, and other inks are printed directly on screen or steel plate with appropriate dilution ratios. They are simply used as working electrodes, with commercial reference electrodes and platinum indicator electrodes for detection, such as Josephwang in 1996. Human [Joseph Wang, Prasad V. a. Pamidi, De〇g Su Park, Anal

Chem ·, 1996, 68, 2705-2708 ·] The use of conductive ink printed electrodes in combination with sol-gel technology to modify the enzyme electrode was used as a working electrode, under the application of 1_0V (compared to the silver vaporized silver reference electrode) detection Measure glucose and hydrogen peroxide and develop biochemical sensors. Because the reference electrode is generally not easy to be miniaturized, this is because the early conductive printing ink was mainly made of silver. It was necessary to prepare the silver / vaporized silver or saturated calomel electrode compared to the working electrode or the dual electrode. The process is much more complicated. Because it involves printing silver ink, then an insulating layer needs to be printed, and finally electroplating gas is used to form vaporized silver. However, due to the complexity of the process, the three-electrode system cannot be completely printed. The process directly performs electrode preparation. However, the above-mentioned preparation method is still used in the process of the micro-electrode M252016 electrode, through Hiroaki Suzuki et al. [Hiroaki Suzuki, Hisanori Shiroishi, Satoshi Sasaki, Isao Karube, Anal.

Chem ·, 1999, 71, 5069-5075 ·], in order to successfully use the Ag / AgCl reference electrode on the microchip, the reference electrode must be prepared by thick film printing technology. First, a conductive silver paste is printed on the substrate. Then, a layer of polyimide-based insulation layer is printed, and a 50 pm wide groove is etched. AgC is formed on the score of the groove. Finally, AgCl is printed by screen printing on AgCl. KC1's hydrophilic polymer is used as a liquid junction to block the analysis solution to complete the preparation of the reference electrode. At present, the method of preparing reference electrodes by printing electrodes is mainly this method. However, after five years of developing electrode detection systems using printing technology, the advanced printing ink preparation technology has been able to directly prepare printing inks containing Ag / AgCl. Therefore, a simple preparation technology combining three electrode methods has begun. The steps are also simpler than before, such as

Gabnele-Christine Chemnitius et al. [Ansgar Erlenkotter, Mike Kottbus, Gabriele_Christine Chemnitius, Journal 〇f Electroanalytical Chemistry, 2000, 481, 82-94 ·] Printed technology is used to prepare dual electrodes made of platinum, carbon-based working electrodes, And the reference electrode mainly composed of Ag / AgCl, with the coordination center of Fe2 + / Fe3 + formed by j ^ FeCCN) 6 as the electron transporter, under the applied potential 0.6v (vs · Ag / AgCl) To detect hydrogen peroxide and cooperate with enzyme fixation to develop biochemical sensors. The entire printed electrode technology has also recently developed to a fairly complete state. '/, Simple platemaking is required. With automatic printing technology, various micro-sensing systems can be developed at the M252016 exhibition. The scope is quite extensive, including environmental chemistry. Detection, biochemical detection, clinical detection, etc. The detection objects also include aqueous solutions, non-aqueous solutions, clinical blood samples, medical gas detection, etc. It also shows the widespread use of printed electrodes, almost all the energy of commercial electrochemical systems The measured substances and printed electrodes can be completed and can be further miniaturized. In the detection of water-insoluble substances, U. Wollenberger et al. [U. Wollenberger, B. Neumann, FW Scheller, Electrochimica Acta, 1998, 43, 3581-3585 ·] used printed electrode technology to convert FePC (iron phthalocyanine) Modified with peroxidase on the electrode surface, and used its biochemical reaction to perform electrochemical detection of aliphatic hydrocarbons in an aqueous solution containing a small amount of alcohol; and in the part of the gas molecule detection, such as JP · Hart et al. [JP Hart, AK Abass, Anal. Chim · Acta, 1997, 342, 199-206 ·] use printing technology to modify CoPC (Cobalt phthalocyanine) on the working electrode. For H2S in the air (0_6V vs . Ag / AgCl), CH3SH (0.5V) and other sulfur

Gas detection; and finally, the three-electrode combined detection method, B

Strehlitz et al. [B. Strehlitz, B. Grundig, K. Kopinke, Anal

Chim. Acta, 2000, 403, 11-23 ·] developed a three-electrode system using printed electrode technology to prepare polyaniline modified electrodes, which was used for detection at 0.3v (vs. Ag / AgCl) Ammonia ions, combined with enzyme modification technology, enzymes that generate ammonium ion metabolites will be fixed on the working electrode with poly (carbamyl sulphonate hydrogel) and applied to For general biochemical testing.

Although in recent years, the development of electrochemical sensing II 8 M252016 system using printed electrode technology has gradually become the mainstream of related experiments, but due to the lack of thorough discussion of related materials, the printing process, electrode style, electrode and substrate material matching The upper and lower parts are still not optimized, so that during detection, there is still a relatively high rate of change, which has the disadvantage of poor reproducibility. In addition, Ying Xiao, based on the principle of siphonic capillary action, puts its concept on the current medical testing test strips, making analysis samples from the traditional sampling method of dripping from the opening above the test strip, improving the current film Side sampling mode, @ a 盘 7A 虫 & Designed by Ya and Fei 4 疋 in order to avoid the opportunity for patients to get in touch with the instrument, to avoid cross-contamination, and it uses a simple sampling method of suction; the amount of analysis samples required is very small It is suitable for analysis and detection in various situations. Based on the principle, the gap distance affects the capillary effect very much, which results in an error in the sample size, which affects the accuracy of the detection, resulting in a very high rate of change, which also makes the analysis data. Demonstrates poorly linear results. [New content] In this work, the catalyst is directly fixed to the working electrode with a selectable area and size to develop an appropriate three-electrode detection platform and solve the problems encountered in the two-electrode electrochemical detection. This creation also proposes a suitable electrode style and suitable packaging ’to make the current density distribution uniform, and to achieve a convenient automatic suction micro-volume constant volume sampling, so a fixed amount of reaction volume is provided, which can avoid measurement errors. [Embodiment] In this article, a siphon-printed three-electrode M252016 electrochemical test strip that can be mass-produced is designed to be used in conjunction with capillary siphon to design a micro-sample recognizable micro-sampling method to measure various substances in solution. The scope of application may include general environmental chemical testing, as well as common physiological related medical testing. The siphon-printed three-electrode electrochemical quantitative test strips of this creation include: 1 · Screen printing substrate, which can be all kinds of white plastic or plastic synthetic paper, where plastic can be PP, PE, PVC, PET ·· · Same material, thickness is between 01mm ~ 2mm, can be printed on various carriers. 2. The conductive part of the dual electrode and electrode line can be conductive ink made of carbon, gold, silver, and platinum. It can be directly printed on the above substrate with screen and steel plate. It is not necessary to first print a conductive substance on the substrate to improve conductivity. degree. 3 · The reference electrode can be silver or silver / gasified silver conductive ink, which can be printed on the conductive part of the electrode circuit, or directly printed on the above substrate with screen and steel plate, without the need for the substrate. First, a conductive substance is printed to improve the conductivity. The electrode can be a conductive ink with carbon, gold, silver, and platinum port mixed with a catalyst. It can be printed on the conductive tail of the electrode line, and it can be prepared by steel plate or screen. The “printing and edge layer” is mainly insulated and non-conductive ink. It can be used in combination with screen printing and wound-making ”. The drying method can be heat drying and UV irradiation reaction. The P insulated wire part should not be in contact with the liquid to be tested. Part ′ is mainly a mesh made of high-molecular fiber material, which is used to uniformly distribute the liquid σ ^ ^ ^ ~ in the reaction zone on the substrate. And the field sample distribution ^ "luxury"; m, and ci, when the test area can be used to identify and analyze whether the dissolved M252016 solution is evenly distributed on the electrode with the naked eye recognition area, a simple confirmation action. Person 7 · The cover film part is mainly a polymer material cover film, which is attached to the substrate to cover the insulating layer and the filter is fixed ^, and an appropriate hole is opened in the cover film. In order to provide whether the exhaust gas and the liquid are sucked into the reaction zone ^ for visual inspection, in which a portion of the substrate that is not covered with the insulating layer, and a cover film are provided with a gap for capillary / siphon action to be measured Liquid is drawn into the electrode reaction zone on the substrate. A method suitable for preparing the siphon-printed three-electrode electrochemical mass detection test piece of the present invention, as shown in Figs. 1 to 5, includes the following steps: 1. Cut an appropriate synthetic paper substrate 10 and place it on a carrier Waiting for printing. 2. Print the two-electrode lead wires 30 on the substrate, and use them as the reference electrode, working electrode, and counter electrode leads from right to left, and then 40 to 50. 〇 Bake for 40 minutes, in which the arc-shaped bottom end of the leftmost lead is used as a pair of even electrodes 20, as shown in FIG. 3. Print the reference electrode 40 on the substrate. The area of the electrode does not need to be too large. It should be partially overlapped with the bottom end of the rightmost wire of the three printed wires. Dry at 40 ~ 50 ° C for 40 minutes. as shown in picture 2. 4. Print the working electrode 50 on the substrate. The ink in this part must be uniformly mixed with the catalyst before printing, and the printed part must completely overlap the round part of the bottom end of the middle wire of the two wires printed before. Dry at 40 ° C for 40 minutes, as shown in Figure 2. 5 · Print an insulating layer 60 on the substrate. This insulating layer 60 will cover unnecessary wires to avoid contact with the liquid to be measured, and define a C-shaped reaction area, and then dry it at 50 ~ 60QC. 40 minutes or UV light for 1 minute, as shown in Figure 3 of 11 M252016. 6. Cut a fixed-size hydrophilic filter 70 and place it flat on the c-shaped reaction area, as shown in Fig. 4. 7. A single-sided adhesive polymer cover film 80 with a perforation 81 is applied to the substrate 10 as a counterweight and is applied to the substrate 10 to fix the filter screen and form a capillary / siphon action zone at the bottom end. The perforation 81 of the cover film is on the C-shaped reaction area to identify the exhaust gas and the liquid being sucked. The three-electrode electrochemical quantitative test strip created in this article needs to cooperate with the three-electrode potentiometer system to detect in the appropriate working potential interval (relative to the reference electrode) between 2V and -2V. The distance between the electrodes depends on the pitch of the socket, and can be 0.5 mm and 1.0 mm. Screen-printed electrodes have been developed in recent years because of high-tech participation and the involvement of new materials, and have developed a new generation of electrodes that are inexpensive, can be produced in large quantities, are easy to carry, 6X juice is variable, and has discardable characteristics. Because it can be combined with computer plate making and modern printing technology, "X» ten electrodes, combined with different printing colloids, can be printed on cheap plastic synthetic paper in large quantities, and it is provided as a disposable test strip. This creative siphon type test strip provides a convenient and simple system to avoid the subject from being polluted by the electrode during sampling, and it can also analyze trace samples. In addition, the identification method with the naked eye can reduce the risk of sample The error caused by insufficient quantity improves the accuracy of measurement. [Brief description of the figure] 12 M252016 Figure 1 shows a schematic plan view of the siphon printed three-electrode electrochemical quantitative detection test piece prepared after the creation of the lead printed on the substrate. Figure 2 shows a schematic plan view after the reference electrode and the working electrode are printed on the substrate of Figure 丨. FIG. 3 is a schematic plan view showing an insulating layer printed on the substrate of FIG. 2. FIG. 4 is a schematic plan view showing a flat pin of a hydrophilic strainer placed on a c-shaped reaction zone on the substrate of FIG. 3.

-Fig. 5 shows a schematic plan view after an upper cover film is attached to the substrate of Fig. 4. Description of the drawing number of the main components 10. · Base material; 20 ·. Dual electrode 50 · · Working electrode; 60 · · Insulating layer; Sub-cover film; 81. · Perforation; 3 0. 〇 ·· Hydrophilic filter; 80 · .High score

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Claims (1)

M252016 范围 Application scope: i • A siphon printed three-electrode electrochemical quantitative detection test strip, which includes a substrate; a patterned wire attached to a surface of the substrate, including three spaced-apart wires, the One end of the three wires is suitable for electrically connecting an electrochemical analysis instrument, and the other ends of the three wires respectively include a pair of dual electrodes, a working electrode and a reference electrode, wherein the dual electrodes have a circular arc shape; the working electrode is located near A point at the center of the arc and containing a catalyst for electrochemical reaction, and the reference electrode is located on the periphery of the arc and near the working electrode; an insulating layer is attached to the surface of the substrate and covered The middle section of the three wires allows the two ends of the three wires to be separated by it, and the insulating layer further surrounds the dual electrode, the working electrode and the reference electrode, but exposes the bottom of the circular arc-shaped dual electrode to form a c-shaped reaction zone; a selective hydrophilic filter covering the c-shaped reaction zone; and a cover film having a Holes, and the cover film is attached to the substrate to cover the C-shaped reaction zone, so a gap is formed in the opening of the C-shaped reaction zone and between the cover film and the substrate, and the The perforation is located above the C-shaped reaction area, wherein the gap has a capillary effect and the perforation has an exhaust effect, so that a liquid contacting the gap is sucked into the c-shaped reaction area. 2. The test strip as described in item 1 of the scope of patent application, wherein the substrate M252016 is a non-conductive polymer substrate. 3. The test strip as described in item 2 of the patent application scope, wherein the substrate is a copolymer or blend of polyethylene, polypropylene, polyvinyl chloride, polyester, or the like. 4. The test strip as described in item 1 of the scope of patent application, wherein the three wires are printed on the substrate using conductive ink and the leftmost wire end of the three wires has an arc shape directly as the dual electrode . 5. The test strip described in item 4 of the scope of patent application, wherein the conductive ink contains carbon, gold, silver, or platinum. 6. The test strip as described in item 1 of Shenyan's patent scope, wherein the reference electrode is printed on the substrate and the rightmost lead among the three leads using conductive ink containing silver or silver / vaporized silver. On the end. 7. The test strip as described in item 1 of the scope of the patent application, wherein the working electrode is printed with a conductive ink mixed with a catalyst, and is printed on a round dot at the end of the middle lead among the three leads. 15 M252016 9. The test strip as described in item 1 of the scope of patent application, wherein the catalyst can electrocatalyze the target substance in the liquid to be tested or the product obtained after electrocatalytic reaction of an enzyme with the target, and reduce the electrochemical The reaction potential is used for quantitative work based on the obtained current signal. 16