Taste sensor based on electrical signal, preparation method and detection method thereof

Abstract

The present application relates to a kind of taste sensor based on electrical signal, preparation method and its detection method.Taste sensor device structure is constituted by one metal / metal oxide functional electrode and three Ag / AgCl electrodes deposited on substrate, wherein metal layer and Ag electrode are deposited on substrate by evaporation deposition, and metal oxide functional layer and AgCl layer are formed on it by electrochemical method, and taste simulation and identification function are realized by measuring the potential between metal / metal oxide functional electrode and Ag / AgCl electrode and the conductance and alternating current impedance between the other two Ag / AgCl electrodes.The taste sensor of the present application has the characteristics of simple preparation process, fast measurement response and wide application, etc.

Description

Technical Field

[0001] This invention relates to a taste sensor and its preparation method, specifically to a taste sensor and its preparation method and detection method that realizes taste recognition based on the electrical signal response of the potential, conductivity and AC impedance of the analyte. Background Technology

[0002] Taste refers to the sensation experienced when taste receptors are stimulated by soluble chemical substances, resulting in excitation signals at the cellular level being transmitted to the taste center in the brain, and then undergoing complex perceptual integration. As one of the most important human senses, artificial taste sensors, designed biomimeticly to mimic human taste perception, can avoid the influence of individual subjective factors on the results and have wide applications in food identification, drug testing, and component analysis.

[0003] In recent years, significant progress has been made in the research of taste sensors, which can now accurately identify various tastes such as sour, sweet, bitter, and salty, and provide quantitative concentrations and analyze the components of fruit juice raw materials. Current taste sensors mainly employ two sensing methods: potentiometry and voltammetry. Sensor materials mostly utilize lipid polymers, conductive polymers, and others such as carbon paste, phthalocyanine, and Prussian blue. However, in taste sensors based on these materials, especially organic polymers, the controllability and uniformity of film formation still present challenges, leading to issues with the stability and repeatability of the prepared taste sensors. Summary of the Invention

[0004] This invention aims to provide a taste sensor based on electrical signals and its fabrication method. This structure measures electrical signals such as solution conductivity, AC impedance, and potential difference through functional electrodes in the device, achieving biomimetic taste perception and component identification. The device structure is based on inorganic materials and has the advantages of high sensitivity, good stability, and strong repeatability.

[0005] This invention provides a taste sensor based on electrical signals. The structure comprises a substrate, a metal bottom electrode, a metal oxide functional layer, an Ag bottom electrode, and an AgCl layer. The functional electrode is formed by the metal bottom electrode and the metal oxide functional layer, and the Ag bottom electrode and the AgCl layer form an Ag / AgCl electrode. One set of functional electrodes and three sets of Ag / AgCl electrodes are deposited on the substrate surface.

[0006] This structure connects to an external circuit via a metal bottom electrode and three Ag electrodes to measure corresponding electrical signals. The invention measures the potential signal through the potential difference between the metal bottom electrode and one of the Ag bottom electrodes, and measures the conductance and AC impedance signals respectively through the other two Ag bottom electrodes connected to the external circuit. Based on these electrical signals, a taste sensor function is achieved.

[0007] The improved scheme of this invention can enrich the structural design of taste sensor devices under this structure, or realize more complex device functions. The substrate can be a rigid substrate (such as glass, silicon wafer, etc.) or a flexible film (such as polymer films such as polyimide, polydimethylsiloxane, etc.) to realize a bendable flexible device. The electrode structure can be patterned using masking or photolithography processes to achieve special functions. The metal oxide functional layer can be made of oxide materials such as NiOx, TiOx, IrOx, etc., to meet different sensitivity requirements.

[0008] The present invention also provides a detection method for the above-mentioned taste sensor based on electrical signals, which realizes the simulation and recognition of the taste of the test solution by measuring the solution potential, conductivity and AC impedance electrical signals.

[0009] Specifically, the taste sensor obtains the solution potential by measuring the potential difference between the functional electrode and one of the sets of Ag / AgCl electrodes.

[0010] Specifically, the taste sensor calculates the solution conductivity and AC impedance by applying DC and AC voltages between the two sets of Ag / AgCl electrodes and measuring the current signal.

[0011] The present invention also provides a method for preparing the above-mentioned taste sensor based on electrical signals, comprising the following steps:

[0012] (1) Fabrication of functional electrodes

[0013] Clean the substrate;

[0014] A metal layer is deposited on the surface of the substrate by vacuum evaporation, and the metal layer is a strip-shaped metal thin film.

[0015] The metal layer is prepared in situ by electrochemical oxidation to obtain a metal oxide functional layer. At the same time, during the process, part of the metal layer is exposed by methods such as shielding or selective corrosion to serve as a metal bottom electrode for connecting external circuits.

[0016] (2) Preparation of Ag / AgCl electrode

[0017] First, strip-shaped A atoms are deposited on the surface of the substrate using a vacuum evaporation method. g Metal layer;

[0018] Then, part of the Ag metal layer is reacted in situ by an electrochemical method to obtain an AgCl layer. At the same time, during the process, part of the Ag metal layer is exposed by methods such as shielding or selective etching to serve as the Ag bottom electrode for connecting the external circuit.

[0019] Compared with existing technologies, the taste sensor of the present invention has the advantages of simple preparation process, fast measurement response and wide application. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the device of the present invention;

[0021] Figure 2 This is a schematic diagram of the preparation process of the present invention;

[0022] Figure 3 This is a potential-concentration curve of citric acid measured according to the present invention;

[0023] Figure 4 This is a conductivity-concentration curve of NaCl solution measured according to the present invention;

[0024] Figure 5 This invention provides a three-dimensional scatter plot of the potential, conductivity, and AC impedance of several different solutions. Detailed Implementation

[0025] The taste sensor, its preparation method, and its detection method of the present invention will be described in detail below with reference to the accompanying drawings, and exemplary embodiments of the present invention will be presented.

[0026] See appendix Figure 1 In the diagram, A is a top view and B is a front view. The device structure of this invention includes five parts: a substrate 11, a metal bottom electrode 12, a metal oxide functional layer 13, an Ag bottom electrode 14, and an AgCl layer 15. Specifically, the structure comprises a set of functional electrodes and three sets of Ag / AgCl electrodes deposited on the substrate 11. The functional electrodes are composed of the metal bottom electrode 12 and the metal oxide functional layer 13, and the Ag / AgCl electrodes are composed of the Ag bottom electrode 14 and the AgCl layer 15.

[0027] The substrate 11 can be a rigid carrier (such as glass, silicon wafer, etc.) or a flexible film (such as polyimide, polydimethylsiloxane, etc. polymer film) to realize a bendable flexible device. The electrode structure can be patterned through masking or photolithography to achieve special functions. The metal oxide functional layer 13 can be made of oxide materials such as NiOx, TiOx, IrOx, etc., to meet different sensitivity requirements.

[0028] In the device structure of this embodiment, the substrate 11 is polyimide, the metal bottom electrode 12 is Ti, and the metal oxide functional layer 13 is TiO2. When the device of this embodiment works as a taste sensor, the taste function is simulated by the potential difference between the metal bottom electrode 12 and one of the Ag bottom electrodes 14, and the conductivity between the other two Ag bottom electrodes 14.

[0029] See appendix Figure 2 The processing technology of the taste sensor of the present invention includes the following steps:

[0030] A) A 100 nm of metallic Ti is deposited on a polyimide substrate 11 by electron beam evaporation as a metal bottom electrode 12;

[0031] B) In a mixed solution of NaF and Na2SO4, a voltage of 1V is applied, and TiO2 is obtained by selectively oxidizing part of the metal Ti through an electrochemical method, which serves as the functional layer 13 of the metal oxide;

[0032] C) Three strip-shaped Ag metal bottom electrodes 14, each 100 nm in diameter, are deposited on a polyimide substrate 11 by electron beam evaporation;

[0033] D) In ​​a 1M KCl solution, a voltage of 1V is applied to obtain an AgCl layer 15 on the Ag surface by electrochemical method, which serves as a reference electrode.

[0034] The measurement of sour taste using the device taste sensor of this invention, taking citric acid as an example, is achieved by measuring the concentration of citric acid through the potential difference between the metal bottom electrode 12 and one of the Ag bottom electrodes 14. Figure 3 This is a potential-concentration curve.

[0035] The present invention measures saltiness using NaCl as an example. The NaCl concentration is measured by measuring the conductivity between two Ag bottom electrodes 14. (See attached diagram.) Figure 4 This is a conductivity-concentration curve.

[0036] Appendix Figure 5 The device of this invention is applied to the measurement results of beverage identification. The potential is obtained by measuring the potential difference between the solution metal bottom electrode 12 and one of the Ag bottom electrodes 14 respectively. DC and AC voltages are applied between the other two Ag bottom electrodes 14 to measure the conductance and 100Hz AC impedance signal, thereby realizing the identification of six beverages: lemon juice, orange juice, grape juice, cola, sugar-free cola and yogurt.

[0037] The above description merely illustrates preferred embodiments of the present invention, and while the description is relatively specific and detailed, it should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications, improvements, and substitutions without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this patent should be determined by the appended claims.

Claims

1. A taste sensor based on electrical signals, characterized in that: The taste sensor mainly includes a substrate (11), a set of functional electrodes deposited on the substrate (11) and three sets of Ag / AgCl electrodes. The functional electrodes are composed of a metal bottom electrode (12) and a metal oxide functional layer (13), and the Ag / AgCl electrodes are composed of an Ag bottom electrode (14) and an AgCl layer (15). The metal oxide functional layer (13) is selected from NiOx, TiOx or IrOx.

2. The taste sensor based on electrical signals according to claim 1, characterized in that: The substrate (11) is selected as a rigid carrier or a flexible film; the rigid carrier is glass or silicon wafer; the flexible film is a polymer film made of polyimide or polydimethylsiloxane.

3. A detection method for a taste sensor based on electrical signals as described in any one of claims 1 or 2, characterized in that: The taste sensor simulates and identifies the taste of the solution being tested by measuring the solution potential, conductivity, and AC impedance electrical signals.

4. The detection method of a taste sensor based on electrical signals according to claim 3, characterized in that: The taste sensor obtains the solution potential by measuring the potential difference between the functional electrode and one of the sets of Ag / AgCl electrodes.

5. The detection method of a taste sensor based on electrical signals according to claim 3, characterized in that: The taste sensor calculates the solution conductivity and AC impedance by applying DC and AC voltages between the two sets of Ag / AgCl electrodes and measuring the current signal.

6. A method for preparing a taste sensor based on electrical signals as described in any one of claims 1 or 2, characterized in that, The preparation method includes the following steps: (1) Fabrication of functional electrodes Clean the substrate (11); A metal layer is deposited on the surface of the substrate (11) by vacuum evaporation. The metal layer is prepared by in-situ reaction of electrochemical oxidation to obtain a metal oxide functional layer (13), while exposing part of the metal layer as a metal bottom electrode (12) for connecting external circuits. (2) Preparation of Ag / AgCl electrode First, an Ag metal layer is deposited on the surface of the substrate (11) by vacuum evaporation. Then, part of the Ag metal layer is reacted in situ by an electrochemical method to obtain an AgCl layer (15), while part of the Ag metal layer is exposed as an Ag bottom electrode (14) for connecting the external circuit.

Images