Polyamide thin layer dual channel electrochemical sensor

Abstract

The application discloses a polyamide thin layer double-channel electrochemical sensor, which comprises a PET plate, silver paste conducting wire, insulating oil layer, carbon paste and polyamide thin film layer, the outer side of the upper end of the PET plate is provided with the silver paste conducting wire through silk screen printing, and the outer side of the upper end of the PET plate and the silver paste conducting wire is provided with the insulating oil layer; the outer side of the upper end of the insulating oil layer is provided with the carbon paste through silk screen printing, the middle parts of two groups of circular electrodes are provided with square electrodes in alignment, and the outer side of the upper end of the carbon paste is provided with the polyamide thin film layer. The application belongs to the technical field of electrochemical sensors, and achieves the technical effects that the circular electrodes are double working electrodes, the square electrodes are counter electrodes, the silver wire is connected as a reference electrode, the concentration of ECH and VB can be rapidly detected, the polyamide thin film layer is immobilized on the circular electrodes and the square electrodes, the sample pretreatment steps are simplified, and the problems of long analysis time, high analysis cost, poor reproducibility and poor accuracy are solved.

Description

Technical Field

[0001] This application relates to the field of electrochemical sensor technology, specifically to a polyamide thin-film dual-channel electrochemical sensor. Background Technology

[0002] Cistanche deserticola (Ma) is a plant belonging to the genus Cistanche in the family Orobanchaceae of the order Lamiaceae. It has the effects of tonifying kidney yang, nourishing essence and blood, and moistening the intestines to relieve constipation. Ma contains abundant bioactive components, which have pharmacological effects such as regulating immunity, relieving physical fatigue, protecting the liver, and moistening the intestines to relieve constipation. The chemical components of Ma mainly include phenylethyl glycosides, iridoids and their glycosides. Active components include echinacoside (ECH), verbascoside (VB), iridoids, and lignans. Among them, echinacoside and verbascoside have various biological activities and important pharmacological effects. Therefore, electrochemical sensors are needed to quantitatively analyze the two active components, echinacoside and verbascoside, in Cistanche deserticola.

[0003] However, most electrochemical sensors currently only use high performance liquid chromatography, ultraviolet spectrophotometry, and capillary electrophoresis to determine the content of ECH and VB in Ma. This results in long analysis time, high analysis cost, high instrument price and daily maintenance cost, and poor reproducibility and accuracy in the determination process. Summary of the Invention

[0004] To address these issues, this application provides a polyamide thin-layer dual-channel electrochemical sensor to solve the problems of long analysis time, high analysis cost, high instrument price and daily maintenance cost, and poor reproducibility and accuracy in the determination of ECH and VB content in Ma.

[0005] To achieve the above objectives, this application provides the following technical solution: A polyamide thin-film dual-channel electrochemical sensor includes a PET plate, silver paste wires, an insulating oil layer, carbon paste, and a polyamide thin film layer. The upper outer side of the PET plate is screen-printed with silver paste wires, and the upper outer side of the PET plate and the silver paste wires are provided with an insulating oil layer. The upper outer side of the insulating oil layer is screen-printed with carbon paste, and a circular electrode is provided in the middle of the carbon paste to pass through the insulating oil layer and contact the silver paste wire. Square electrodes are provided in the middle of the two sets of circular electrodes. A polyamide film layer is laid on the outer side of the upper end of the carbon paste.

[0006] Furthermore, the carbon paste is provided with scale lines on the upper right and rear sides to record the subsequent polyamide film layer running positions.

[0007] Furthermore, the square electrode is in contact with the silver paste wire, and the square electrode serves as the counter electrode, allowing an external silver wire to be connected as a reference electrode.

[0008] Furthermore, the right and rear sides of the polyamide film layer are located inside the scale lines, making it convenient to read the carbon paste values.

[0009] Furthermore, the two sets of circular electrodes are used to detect ECH and VB, respectively.

[0010] Compared with the prior art, this application has at least the following beneficial effects: 1. By using a circular electrode as the dual working electrode and a square electrode as the counter electrode, with an external silver wire as the reference electrode, the concentrations of ECH and VB can be rapidly detected. Combined with the polyamide film layer immobilized on the circular and square electrodes, the sample pretreatment steps are simplified, enabling the circular and square electrodes to more accurately and rapidly detect the active components of ECH and VB in Ma. This solves the problems of long analysis time, high analysis cost, and high instrument price and daily maintenance costs. 2. By modifying circular and square electrodes with β-CD@MWCNTs, the specific adsorption of target molecules is enhanced through the inclusion effect of β-CD, thereby improving the detection sensitivity. Attached Figure Description

[0011] To more intuitively illustrate the prior art and this application, exemplary drawings are provided below. It should be understood that the specific shapes and structures shown in the drawings should not generally be regarded as limiting conditions for implementing this application; for example, based on the technical concept disclosed in this application and the exemplary drawings, those skilled in the art are capable of making conventional adjustments or further optimizations to the addition / reduction / classification of certain units, their specific shapes, positional relationships, connection methods, size ratios, etc.

[0012] Figure 1 This is a schematic diagram of the overall exploded structure of a polyamide thin-film dual-channel electrochemical sensor provided in one embodiment of this application; Figure 2 This is a top view of a polyamide thin-film dual-channel electrochemical sensor provided in one embodiment of this application.

[0013] Explanation of reference numerals in the attached figures: 1. PET board; 2. Silver paste conductor; 3. Insulating oil layer; 4. Carbon paste; 5. Scale lines; 6. Circular electrode; 7. Polyamide film layer; 8. Square electrode. Detailed Implementation

[0014] The present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0015] like Figures 1 to 2 As shown, the polyamide thin-film dual-channel electrochemical sensor in the first aspect embodiment of this application includes: a PET plate 1, a carbon paste 4 and a polyamide thin film layer 7. The upper outer side of the PET plate 1 is screen-printed with silver paste wires 2, and an insulating oil layer 3 is provided on the upper outer side of the PET plate 1 and the silver paste wires 2. Among them, the silver paste wire 2 is printed on the upper outer side of the PET board 1 through a customized printing screen and squeegee. After the silver paste wire 2 is printed, an insulating oil layer 3 is set on the upper end of the PET board 1 and the silver paste wire 2. The insulating oil layer 3 can block the ion migration path between adjacent electrodes and prevent false signal superposition caused by leakage current.

[0016] Carbon paste 4 is screen-printed on the outer upper end of the insulating oil layer 3. A circular electrode 6 is disposed in the middle of the carbon paste 4, passing through the insulating oil layer 3 and contacting the silver paste wire 2. A square electrode 8 is disposed in the middle of two sets of circular electrodes 6, and the square electrode 8 is in contact with the silver paste wire 2. The circular electrode 6 is a dual working electrode and the square electrode 8 is a counter electrode. A silver wire is connected to the square electrode 8 as a reference electrode to achieve rapid detection of ECH and VB concentrations.

[0017] Two sets of circular electrodes 6 are used to detect ECH and VB, respectively. These two sets of circular electrodes 6 act as two independent sensing interfaces, specifically identifying ECH and VB in the sample. The redox reactions occurring on their surfaces generate measurable current signals, and the concentration of the analyte is deduced from the potential changes. The square electrode 8 is a key node forming a closed loop, responsible for receiving electron flows from the circular electrodes 6 and the square electrode 8 to maintain charge balance.

[0018] Graduation lines 5 are provided on the upper right and rear sides of the carbon paste 4 to record the sampling position of the subsequent polyamide film layer 7. The right and rear sides of the polyamide film layer 7 are located inside the graduation lines 5 for easy reading of the carbon paste 4 values. The polyamide film layer 7 is laid on the upper outer side of the carbon paste 4, and a sampling point is provided above the polyamide film layer 7, which is the origin of the radial diffusion of the solution.

[0019] Before coating the polyamide film layer 7 onto the carbon paste 4, a 5×5cm section of a 0.8mm thick silicone pad needs to be cut according to the electrode design diagram to indicate the location where the polyamide film needs to be coated, so that subsequent coating can proceed.

[0020] The preparation process of polyamide film layer 7 is as follows: Weigh 1g of 200-400 mesh polyamide powder into a beaker, add 6mL of 80% formic acid solution, stir until dissolved and transparent, and let stand for 10min. Then add 3mL of 70% ethanol solution, stir until uniform, and let stand for 20min. Spread a small amount evenly on a pre-prepared silicone pad, then spray water mist onto the polyamide pad one by one with a spray gun to precipitate a white solid. Finally, air dry for 12h to obtain the PAM / β-CD@MWCNTs / SPEs electrochemical sensor.

[0021] The overall setup includes x and y axes, and the overall measurement is divided into two steps: Using the x-axis of the PET plate as the base, insert the circular electrode 6 and the square electrode 8 into the developing cylinder and spot the sample at the spotting point. The sample is developed along the y-axis, and the leading edge of the developing agent reaches the top of the polyamide film layer 7. Then, remove the circular electrode 6 and the square electrode 8 and let them dry.

[0022] With the y-axis as the base, the silver paste lead wire 2 inserts the circular electrode 6 and the square electrode 8 into the development cylinder, connects the contact points to the adapter cable, spots the sample at the spotting point, and the sample develops along the x-axis while continuously performing LSV scanning. The two standards arrive at the circular electrode 6 and the square electrode 8 in turn for subsequent testing.

[0023] Meanwhile, the electrochemical sensor was improved by using the drop-coating method: the aqueous MWCNTs slurry was transferred to a centrifuge tube, an appropriate amount of 1000 μM β-CD solution was added, and the mixture was sonicated for 20 min to obtain the β-CD@MWCNTs material. It was stored at room temperature, drop-coated onto the surface of the circular electrode 6 and the square electrode 8, and dried at 50 °C for storage.

[0024] This application utilizes a dual working electrode system consisting of a circular electrode 6 and a square electrode 8, connected to an external reference electrode, to achieve rapid detection of ECH and VB concentrations. Multiple electrochemical scans using different electrodes revealed that the relative standard deviations (RSDs) of the obtained ECH and VB were all less than 5%, indicating good reproducibility of the method. The working principle of obtaining the RSDs through electrochemical scanning for ECH and VB is prior art and will not be elaborated upon here.

[0025] By immobilizing a polyamide thin film layer 7 on the circular electrode 6 and the square electrode 8, the sample pretreatment steps are simplified, enabling the circular electrode 6 and the square electrode 8 to more accurately and quickly detect the active components of ECH and VB in Ma. This solves the problems of long analysis time, high analysis cost, and high instrument price and daily maintenance costs.

[0026] Meanwhile, β-CD@MWCNTs were modified on the circular electrode 6 and the square electrode 8. The inclusion effect of β-CD enhanced the specific adsorption of target molecules and improved the detection sensitivity.

[0027] The technical features of the above embodiments can be combined in any way (as long as there is no contradiction in the combination of these technical features). For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described; these embodiments not explicitly written should also be considered to be within the scope of this specification.

Claims

1. A polyamide thin-film dual-channel electrochemical sensor, comprising a PET plate (1), silver paste wires (2), an insulating oil layer (3), carbon paste (4), and a polyamide thin film layer (7), characterized in that, The upper outer side of the PET board (1) is screen-printed with silver paste wires (2), and the upper outer side of the PET board (1) and the silver paste wires (2) are provided with an insulating oil layer (3). The upper outer side of the insulating oil layer (3) is screen-printed with carbon paste (4), and a circular electrode (6) is provided in the middle of the carbon paste (4) to pass through the insulating oil layer (3) and contact the silver paste wire (2). A square electrode (8) is provided in the middle of the two sets of circular electrodes (6). A polyamide film layer (7) is laid on the outer side of the upper end of the carbon paste (4).

2. The polyamide thin-film dual-channel electrochemical sensor according to claim 1, characterized in that, The carbon paste (4) has scale lines (5) on the upper right and rear sides to record the running position of the subsequent polyamide film layer (7).

3. The polyamide thin-film dual-channel electrochemical sensor according to claim 1, characterized in that, The square electrode (8) is in contact with the silver paste wire (2), and the square electrode (8) serves as the counter electrode, and can be connected to an external silver wire as a reference electrode.

4. The polyamide thin-film dual-channel electrochemical sensor according to claim 1, characterized in that, The right and rear sides of the polyamide film layer (7) are located inside the scale line (5), which makes it convenient to read the value of the carbon paste (4).

5. The polyamide thin-film dual-channel electrochemical sensor according to claim 1, characterized in that, The two sets of circular electrodes (6) are used to detect ECH and VB, respectively.

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