An application of a solid-liquid-gas three-phase interface enzyme electrode based on iron oxide nanowire array in biosensors
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SUZHOU UNIV
- Filing Date
- 2023-08-31
- Publication Date
- 2026-06-30
Smart Images
Figure CN117147652B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of biosensor technology, and in particular to a solid-liquid-gas three-phase interface enzyme electrode based on an iron oxide nanowire array and its application in biosensors. Background Technology
[0002] According to the World Health Organization, diabetes has become the seventh leading cause of death worldwide, significantly impacting lifespan and quality of life for modern people. Therefore, accurate detection of glucose levels in the human body is crucial for the diagnosis of diabetes and the maintenance of normal vital signs in diabetic patients. Based on the method of detecting hydrogen peroxide, a product of enzyme-catalyzed reactions, traditional glucose oxidase-based sensing systems can be divided into two types: the hydrogen peroxide oxidation method and the hydrogen peroxide reduction method. Because common substances in living organisms such as ascorbic acid and dopamine can be simultaneously oxidized with hydrogen peroxide at the same oxidation potential, this greatly reduces the accuracy of the oxidation method. The biggest problem with the reduction method is that oxygen and hydrogen peroxide have similar reduction potentials; the simultaneous reduction of oxygen also affects the reduction current of hydrogen peroxide, which is also detrimental to accurate glucose detection.
[0003] In the existing technology, the catalyst in the three-phase enzyme electrode structure of metal oxide given in the solid-liquid-gas three-phase interface has unstable morphology, is not tightly bound to the substrate, is easy to fall off, and has an unsatisfactory ability to catalyze the reduction of H2O2. Moreover, the substrate used in the three-phase enzyme electrode is mostly a planar metal sheet, and the air inlet channel connected to the atmosphere is only on the same side of the enzyme layer and the catalyst layer, which may result in insufficient gas supply.
[0004] While developing catalysts with hydrogen peroxide reduction selectivity can solve the problem of glucose sensing accuracy, the performance of enzyme electrodes is still limited by the "oxygen deficiency" problem at the reaction interface. In traditional solid-liquid two-phase interface enzyme electrodes, the oxygen required for the enzymatic reaction can only be provided by dissolved oxygen in the liquid phase. However, due to the low solubility and slow transport rate of oxygen in the liquid phase, it is difficult to replenish it to the reaction interface in a timely manner. This undoubtedly limits the kinetics of enzyme catalysis, directly resulting in a narrow detection linear range of the enzyme electrode. Summary of the Invention
[0005] To address the aforementioned technical problems, this invention provides an iron oxide nanowire catalyst with hydrogen peroxide reduction selectivity, and based on this catalyst, an enzyme electrode with a solid-liquid-gas three-phase interface is prepared. This invention uses a titanium mesh as a conductive substrate to grow an iron oxide nanowire array. Based on this array, glucose oxidase is modified with a low surface energy material and loaded onto it to obtain a three-phase enzyme electrode with superhydrophobic properties. When the three-phase enzyme electrode is immersed in an aqueous solution, only the top of the enzyme electrode is wetted, thus forming a solid-liquid-gas three-phase interface at the reaction interface. The oxygen required for the enzyme-catalyzed reaction can be directly provided by the gas phase, ensuring a sufficient and constant oxygen level at the reaction interface, thereby greatly improving the rate and limit of the enzyme-catalyzed reaction and thus enhancing the linear range of glucose detection. Simultaneously, the hydrogen peroxide product of the enzyme-catalyzed reaction is selectively reduced by the iron oxide catalyst, further improving the accuracy of glucose detection. In summary, this invention can significantly improve the detection performance of electrochemical glucose sensors, including sensitivity, accuracy, and linear range, thereby enabling accurate detection of glucose over a wide concentration range.
[0006] The first objective of this invention is to provide a solid-liquid-gas three-phase interface enzyme electrode based on an iron oxide nanowire array. The three-phase interface enzyme electrode includes a substrate, a catalyst grown on the substrate, and an oxidase layer supported on the catalyst surface. The catalyst is selected from iron oxide nanowires with an array structure. The iron oxide nanowire array structure described in this invention uses nanowires with a specific orientation, which is more conducive to the directional transport of electrons and the construction of the three-phase structure.
[0007] In one embodiment of the present invention, the substrate is selected from any one of copper mesh, titanium mesh, nickel mesh, and carbon cloth.
[0008] In one embodiment of the present invention, the length of the iron oxide nanowire is 100-300 nm.
[0009] In one embodiment of the present invention, the three-phase interface enzyme electrode is prepared by the following method:
[0010] (1) An iron oxide nanowire array was grown in situ on a conductive substrate. After the reaction, the substrate was washed and dried to obtain a conductive substrate loaded with an iron oxide nanowire array.
[0011] (2) The substrate loaded with iron oxide nanowire array in step (1) is calcined at a high temperature of 350℃-450℃ and hydrophobicated using a low surface energy material to obtain a hydrophobic primary electrode.
[0012] (3) After plasma treatment of the hydrophobic primary electrode obtained in step (2), load the oxidase mixed solution and dry it to obtain the solid-liquid-gas three-phase interface enzyme electrode.
[0013] In one embodiment of the present invention, in step (1), the in-situ growth is preferably carried out by hydrothermal method.
[0014] In one embodiment of the present invention, the reaction solution for the hydrothermal method is a mixed aqueous solution of 0.075 mol / L FeCl3·6H2O and 0.075 mol / L urea, the reaction time is 1-9 h, and the reaction temperature is 100-120 °C.
[0015] In one embodiment of the present invention, in step (1), the detergent used in washing is deionized water or ethanol.
[0016] In one embodiment of the present invention, in step (2), the low surface energy material is selected from one or more of polydimethylsiloxane, fluorosilane, chlorosilane, silane coupling agent, perfluorooctane sulfonic acid, polytetrafluoroethylene and long-chain alkyl compounds.
[0017] In one embodiment of the present invention, in step (3), the oxidase in the oxidase mixture is selected from one or more of glucose oxidase, α-glycerophosphate oxidase, cholesterol oxidase, bilirubin oxidase, creatinine oxidase, galactose oxidase, lactate oxidase, choline oxidase, D-amino acid oxidase, L-amino acid oxidase and L-α-hydroxy acid oxidase.
[0018] In one embodiment of the present invention, the oxidase mixture further includes a cross-linking agent and an enzyme stabilizer.
[0019] In one embodiment of the present invention, the enzyme stabilizer is selected from bovine serum albumin, trehalose, or chitosan.
[0020] In one embodiment of the present invention, the crosslinking agent is selected from one or more of glutaraldehyde, N,N-thiocarbonyldiimidazole, genipin, acetic anhydride, diglycidyl ether, and octyldiimide. Further, glutaraldehyde is preferred.
[0021] The second objective of this invention is to provide a solid-liquid-gas three-phase interface bio-enzyme sensor, including the aforementioned three-phase interface enzyme electrode based on an iron oxide nanowire array.
[0022] In one embodiment of the present invention, the solid-liquid-gas three-phase interface bio-enzyme sensor further includes a reference electrode and a counter electrode.
[0023] In one embodiment of the present invention, the reference electrode is an Ag / AgCl electrode and the counter electrode is a Pt wire.
[0024] A third object of the present invention is to provide the application of the aforementioned solid-liquid-gas three-phase interface bioenzyme sensor in the detection of glucose, sucrose, lactose, uric acid, creatinine, urea, lactic acid, acetylcholine, triglycerides or cholesterol.
[0025] The technical solution of the present invention has the following advantages compared with the prior art:
[0026] The iron oxide nanowire catalyst synthesized in this invention exhibits hydrogen peroxide reduction selectivity within a certain potential window, thus inhibiting oxygen reduction. This improves detection accuracy and is beneficial for the accurate detection of low-concentration substances. Furthermore, the catalyst demonstrates high catalytic selectivity in various pH environments. In addition, compared to traditional solid-liquid two-phase interface biosensors, the electrode prepared in this invention is a solid-liquid-gas three-phase enzyme bioelectrode. The oxygen required for the oxidase catalytic reaction at the reaction interface can be stably supplied directly from the gas phase, thereby solving a series of technical bottlenecks in oxidase electrode sensing caused by low and fluctuating oxygen concentrations in the solution (e.g., limited oxygen concentration at the interface inhibits the kinetics of the oxidase catalytic reaction, thus limiting the detection linear range and reducing detection accuracy). By using a titanium mesh with a micron-scale woven structure as a substrate, this invention allows for simultaneous gas supply to both the front and back sides (the side without catalyst), further increasing the detection upper limit. The oxygen-rich bioenzyme electrode prepared using this method can detect not only low concentrations of glucose but also high concentrations (lowest detection limit is 2 mM, upper detection limit is 50 mM), and can be used to detect glucose in blood. Attached Figure Description
[0027] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein...
[0028] Figure 1 The image shown is a scanning electron microscope image of the solid-liquid-gas three-phase bioenzyme electrode prepared in Example 1 of this invention.
[0029] Figure 2 The linear sweep voltammetric curves of the iron oxide catalyst prepared in Example 1 of this invention in argon-saturated PBS solution, 0.3 mM oxygen PBS solution, and 1 mM hydrogen peroxide PBS solution, as well as the current response in PBS solutions with different oxygen concentrations and PBS solutions containing 0.1 mM and 1 mM hydrogen peroxide;
[0030] Figure 3 The results show the stability of the catalyst prepared in Example 1 of this invention under different pH values tested over a long period of time.
[0031] Figure 4 The result of glucose detection using the oxygen-enriched bioenzyme electrode prepared in Example 1 of this invention;
[0032] Figure 5 This is the result of glucose detection using a conventional two-phase electrode in Example 1 of the present invention;
[0033] Figure 6 The results of detecting 0-1mM glucose using the oxygen-enriched enzyme electrode prepared in Example 1 of this invention;
[0034] Figure 7 The results of detecting glucose in newborn calf serum using the oxygen-enriched enzyme electrode prepared in Example 1 of this invention;
[0035] Figure 8 The results of detecting lactic acid using the oxygen-enriched bioenzyme electrode prepared in Example 2 of this invention;
[0036] Figure 9 This is the result of lactic acid detection using a conventional two-phase electrode in Example 2 of the present invention;
[0037] Figure 10 The results of sucrose detection using the oxygen-enriched bioenzyme electrode prepared in Example 3 of this invention;
[0038] Figure 11 This is the result of sucrose detection using a conventional two-phase electrode in Example 2 of the present invention. Detailed Implementation
[0039] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.
[0040] Example 1
[0041] This embodiment provides a method for preparing a three-phase glucose oxidase bioelectrode based on a selective hydrogen peroxide-reduced iron oxide catalyst, comprising the following steps:
[0042] (1) Pretreatment of conductive substrate: Cut a 200-mesh conductive titanium mesh into a 1cm×2cm rectangle, and clean it with acetone, ethanol and deionized water in sequence for 10 minutes by ultrasonic cleaning and then dry it for later use.
[0043] (2) Hydrothermal reaction synthesis of catalyst: The hydrothermal reaction solution is a mixed aqueous solution of 0.075 mol / L FeCl3·6H2O and 0.075 mol / L urea. The titanium mesh substrate prepared in step 1) is placed at the bottom of the inner liner of the reactor, sealed, and reacted at 100℃ for 3-9 hours. After the reaction is completed, the mixture is cooled down, and the titanium mesh is washed with deionized water and ethanol in sequence to obtain the catalyst precursor grown on the substrate, such as... Figure 1 As shown in a.
[0044] (3) Obtaining iron oxide nanowire array by high temperature treatment: The precursor catalyst obtained in step 2) can be calcined at 350℃ for 3h to obtain an iron oxide catalyst with hydrogen peroxide reduction selectivity. The heating rate is 4℃ / min.
[0045] (4) Hydrophobic treatment: Dissolve 10 μL of 1H,1H,2H,2H-perfluorooctyltrichlorosilane in 10 mL of cyclohexane to prepare a solution, and immerse the catalyst obtained in step 3) in the above solution for 1 h, and then take it out and dry it at 120 °C for 1 h.
[0046] (5) Preparation of glucose oxidase mixed solution: Mix glucose oxidase solution (20mg / mL), bovine serum albumin (15mg / mL), and glutaraldehyde crosslinking agent (5%wt) in a volume ratio of 20:20:1 to obtain the required mixed enzyme solution.
[0047] (6) Enzyme layer modification: The electrode obtained in step 4) is fixed into a square with a working area of 5mm × 5mm. After short-term plasma hydrophilic treatment, a certain volume (5 μL, 7 μL, or 9 μL) of the mixed solution in step 5) is added. After natural drying, the desired oxygen-enriched enzyme electrode can be obtained, such as... Figure 1 As shown in b, the enzyme layer is uniformly covered on the substrate surface and does not penetrate into the substrate interior, thus forming an oxygen-enriched enzyme bioelectrode.
[0048] (7) Electrochemical Testing: Electrochemical testing was performed using a CHI 660E electrochemical workstation with a three-electrode system, with a platinum wire as the counter electrode and Ag / AgCl as the reference electrode. When testing the hydrogen peroxide selectivity correlation performance of the prepared catalyst, the catalyst obtained in step 3) was used as the working electrode, and the testing methods were linear sweep voltammetry (scanning potential 0.2V to -0.5V, scan rate 50mV / s) and chronoamperometry (potential -0.2V). When evaluating the correlation performance of the three-phase glucose oxidase electrode, the oxygen-enriched enzyme electrode was used as the working electrode, and the testing method was chronoamperometry (potential -0.2V) with a scan time of 15s.
[0049] Comparative Example 1
[0050] Compared with a traditional two-phase electrode, its preparation method is similar to that of the electrode in Example 1. The difference is that hydrophobic treatment is not performed here to make it completely hydrophilic.
[0051] Performance test examples
[0052] To test the selectivity of the prepared iron oxide catalyst for hydrogen peroxide reduction, the iron oxide catalyst obtained in Example 1 was subjected to linear sweep voltammetry in a three-electrode system. The scan potential was 0.2V to -0.5V, and the scan rate was 50mV / s. Figure 2As shown in Figure a, the oxygen reduction onset potential of this catalyst is -0.27V, and the hydrogen peroxide reduction potential is 0.08V. This indicates that within the potential range of 0.08V to -0.27V, the catalyst can reduce only hydrogen peroxide without reducing oxygen, thus achieving high selectivity for hydrogen peroxide reduction. To better demonstrate the difference in selectivity, -0.2V, the value of the largest hydrogen peroxide reduction current, was selected as the test potential for the amperometric experiment.
[0053] To further investigate the selectivity of the iron oxide catalyst, amperometric experiments were performed in PBS solutions with six different oxygen concentrations ranging from 0.05 mM to 0.30 mM, 0.1 mM hydrogen peroxide solutions, and 1 mM hydrogen peroxide solutions. Figure 2 As shown in b, under different oxygen concentrations, the current response value of the iron oxide catalyst in the three solutions remained constant. This indicates that changes in the oxygen concentration in the solution have almost no effect on the hydrogen peroxide reduction reaction on the electrode surface. The use of this catalyst can improve the accuracy of glucose detection by the oxygen-enriched enzyme electrode based on it, which is beneficial for the determination of low-concentration glucose content.
[0054] To investigate the stability of the iron oxide catalyst under different pH conditions, long-term amperometric experiments were conducted on the catalyst in PBS solutions with pH values of 4, 7, and 9. Figure 3 As shown, the experimental results under the three conditions all showed a relative standard deviation of less than 3% within 6000s, demonstrating sufficient stability, which is beneficial to improving the stability of the subsequent oxygen-enriched enzyme electrode.
[0055] The electrochemical enzyme sensor obtained in Example 1 and the biosensor obtained in Comparative Example 1 were subjected to glucose amperometric testing at -0.2V with glucose concentrations of 0mM, 5mM, 10mM, 20mM, 30mM, 40mM, 50mM, and 70mM. The experimental results are shown in [Figure number missing]. Figure 4 . Figure 4 Figure a is a graph showing the response current of the sensor in this invention when detecting glucose. The glucose concentrations from top to bottom in the graph are 0 mM, 5 mM, 10 mM, 20 mM, 30 mM, 40 mM, 50 mM, and 70 mM, respectively. Figure 4 As can be seen from point a, it can be used to detect glucose, and the response current increases accordingly with increasing glucose concentration. From
[0056] Figure 4 As can be seen from b, the detection limit of the electrochemical enzyme sensor prepared in Example 1 of the present invention is as high as 50mM.
[0057] Figure 5 The electrochemical enzyme sensor prepared in Comparative Example 1 was subjected to glucose amperometric testing at -0.2V. Figure 5Figure a shows the response current of the sensor detecting glucose in Comparative Example 1. From top to bottom, the glucose concentrations in the figure are 0 mM, 0.1 mM, 0.2 mM, 0.3 mM, 0.5 mM, and 1 mM, respectively. As the glucose concentration increases, the response current increases accordingly. Figure 5 As can be seen from b, the detection limit of the biosensor obtained in Comparative Example 1 is 0.7 mM. Therefore, the detection limit of the biosensor obtained in this invention is approximately 70 times that of the sensor obtained in Comparative Example 1. Furthermore, it can be seen that the electrochemical enzyme sensor obtained in Example 1 of this invention exhibits linear correlation within a concentration range of 50 mM, with the linear equation being y = -0.73x - 6.24, R0. 2 =0.994.
[0058] Figure 6 The results of the electrochemical enzyme sensor obtained in Example 1 of this invention for detecting glucose in the range of 0 mM to 1 mM are shown. Figure 6 The curve in figure a shows the concentration of lactate added at each step from left to right. The glucose concentrations at each plateau from left to right are 0.002 mM, 0.003 mM, 0.005 mM, 0.007 mM, 0.01 mM, 0.02 mM, 0.03 mM, 0.05 mM, 0.1 mM, 0.2 mM, 0.5 mM, 0.7 mM, and 1 mM. Figure 6 As can be seen from b, the electrochemical enzyme sensor obtained in Example 1 of this invention exhibits a linear correlation with the response current in the low concentration range. Figure 5 It can be seen that the lowest detection limit of the electrochemical enzyme sensor prepared by the present invention is 0.002 mM.
[0059] Figure 7 The results of glucose detection in newborn calf serum by the electrochemical enzyme sensor obtained in Example 1 of this invention are shown. Figure 7 The glucose concentrations at each plateau of curve a from left to right are 0 mM, 2 mM, 4 mM, 6 mM, 8 mM, 10 mM, 12 mM, 14 mM, 16 mM, 18 mM, and 20 mM, respectively. Figure 7 As shown in b, within this concentration range, the glucose concentration and electrode current exhibit a linear correlation, with the linear equation being y = -0.07x - 2.39, R... 2 =0.992, the electrochemical enzyme sensor obtained by this invention can realize quantitative detection of glucose in serum.
[0060] Example 2
[0061] The electrode preparation in this embodiment is the same as that in Example 1, except that the glucose oxidase mixture is replaced with a lactate oxidase mixture. Figure 8 The result of the electrochemical enzyme sensor obtained in this embodiment for detecting lactic acid is shown. Figure 8The curves in section a, from top to bottom, represent 0 mM, 5 mM, 10 mM, 15 mM, 20 mM, 25 mM, 30 mM, and 40 mM. (From...) Figure 8 As shown in b, the upper limit of lactic acid detection for the electrochemical enzyme sensor prepared by this method can reach 30 mM. Figure 9 Ampere test of the electrochemical enzyme sensor prepared in Comparative Example 1. Figure 9 Figure a shows the response current of the sensor when detecting lactic acid. From top to bottom, the lactic acid concentrations are 0 mM, 0.05 mM, 0.1 mM, 0.3 mM, 0.5 mM, and 0.7 mM, respectively. As the lactic acid concentration increases, the response current correspondingly increases. Figure 9 As can be seen from b, the detection limit of the biosensor obtained in Comparative Example 1 is 0.3 mM. Therefore, the detection limit of the biosensor obtained in this invention is about 100 times that of the sensor obtained in Comparative Example 1.
[0062] Example 3
[0063] The electrode preparation in this embodiment is the same as that in Example 1, except that the glucose oxidase mixture is replaced with a sucrase mixture. Figure 10 The result of sucrose detection by the electrochemical enzyme sensor obtained in this embodiment. Figure 10 The curves in section a, from top to bottom, represent 0mM, 10mM, 30mM, 50mM, 70mM, 100mM, 150mM, and 200mM. (From...) Figure 10 As shown in b, the upper limit of sucrose detection for the electrochemical enzyme sensor prepared by this method is as high as 100 mM. Figure 11 Ampere test of the electrochemical enzyme sensor prepared in Comparative Example 1. Figure 11 Figure a shows the response current of the sensor when detecting sucrose. From top to bottom, the sucrose concentrations are 0 mM, 0.05 mM, 0.1 mM, 0.3 mM, 0.5 mM, and 0.7 mM, respectively. As the sucrose concentration increases, the response current correspondingly increases. Figure 11 As can be seen from b, the detection limit of the biosensor obtained in Comparative Example 1 is 6 mM. Therefore, the detection limit of the biosensor obtained in this invention is about 17 times that of the sensor obtained in Comparative Example 1.
[0064] Example 4
[0065] The electrode preparation in this embodiment is the same as that in Example 1, except that the hydrothermal reaction solution is replaced with a mixed solution of 0.05 mol / L Fe(NO3)3·9H2O and 0.05 mol / L Na2SO4, and the reaction temperature is adjusted to 120℃.
[0066] Example 5
[0067] The electrode preparation in this embodiment is the same as that in Example 1, except that the conductive titanium mesh substrate is replaced with a conductive carbon cloth substrate.
[0068] Example 6
[0069] The electrode preparation in this embodiment is the same as that in Example 1, except that the conductive titanium mesh substrate is replaced with a copper mesh (200 mesh).
[0070] Example 7
[0071] The electrode preparation in this embodiment is the same as that in Example 1, except that the hydrophobic water solution is replaced by a polydimethylsilane solution diluted 30 times with 1H,1H,2H,2H-perfluorooctyltrichlorosilane.
[0072] Example 8
[0073] The electrode preparation in this embodiment is the same as that in Example 1, except that the hydrophobic water solution is replaced by fluorosilane instead of 1H,1H,2H,2H-perfluorooctyltrichlorosilane.
[0074] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.
Claims
1. A solid-liquid-gas three-phase interface enzyme electrode based on an iron oxide nanowire array, characterized in that, The three-phase interface enzyme electrode includes a conductive substrate, a catalyst grown on the conductive substrate, and an oxidase layer supported on the surface of the catalyst; the catalyst is selected from iron oxide nanowires with an array structure. The three-phase interface enzyme electrode was prepared by the following method: (1) An iron oxide nanowire array was grown in situ on a conductive substrate. After the reaction, the substrate was washed and dried to obtain a conductive substrate loaded with an iron oxide nanowire array. (2) The conductive substrate loaded with iron oxide nanowire array in step (1) is calcined at high temperature and hydrophobically treated with a low surface energy material to obtain a hydrophobic primary electrode. (3) Load the hydrophobic primary electrode obtained in step (2) with an oxidase mixed solution and dry it to obtain the solid-liquid-gas three-phase interface enzyme electrode based on iron oxide nanowire array.
2. The solid-liquid-gas three-phase interface enzyme electrode based on iron oxide nanowire array according to claim 1, characterized in that, The conductive substrate is selected from any one of copper mesh, titanium mesh, nickel mesh, and carbon cloth.
3. The solid-liquid-gas three-phase interface enzyme electrode based on iron oxide nanowire array according to claim 1, characterized in that, The length of the iron oxide nanowires is 100-300 nm.
4. The solid-liquid-gas three-phase interface enzyme electrode based on iron oxide nanowire array according to claim 1, characterized in that, In step (2), the low surface energy material is selected from one or more of polydimethylsiloxane, fluorosilane, chlorosilane, silane coupling agent, perfluorooctane sulfonic acid, polytetrafluoroethylene and long-chain alkyl compounds.
5. The solid-liquid-gas three-phase interface enzyme electrode based on iron oxide nanowire array according to claim 1, characterized in that, In step (3), the oxidase in the oxidase mixture is selected from one or more of glucose oxidase, α-glycerophosphate oxidase, cholesterol oxidase, bilirubin oxidase, creatinine oxidase, galactose oxidase, lactate oxidase, choline oxidase, D-amino acid oxidase, L-amino acid oxidase and L-α-hydroxy acid oxidase.
6. The solid-liquid-gas three-phase interface enzyme electrode based on iron oxide nanowire array according to claim 1, characterized in that, The oxidase mixture also includes a cross-linking agent and an enzyme stabilizer.
7. A solid-liquid-gas three-phase interface bioenzyme sensor, characterized in that, The solid-liquid-gas three-phase interface enzyme electrode based on iron oxide nanowire arrays as described in any one of claims 1-6.
8. The solid-liquid-gas three-phase interface bioenzyme sensor according to claim 7, characterized in that, The solid-liquid-gas three-phase interface bio-enzyme sensor also includes a reference electrode and a counter electrode.
9. The application of the solid-liquid-gas three-phase interface bio-enzyme sensor according to claim 7 or 8 in the detection of glucose, sucrose, lactose, uric acid, creatinine, urea, lactic acid, acetylcholine, triglycerides or cholesterol.