Three-phase interface bio-enzyme photoelectrode, construction method thereof and biosensor
By constructing a three-phase interface bioenzyme photoelectrode with a three-dimensional TiO2 nanowire array, the problem of limited oxidase catalytic reaction was solved, the light capture ability and oxygen transmission were enhanced, and efficient photoelectrochemical enzyme biosensor detection was achieved.
Patent Information
- Application Number
- CN202511287955.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-10
- Publication Date
- 2025-10-17
AI Technical Summary
In existing photoelectrochemical enzyme biosensors, the oxidase catalytic reaction is limited by the slow oxygen diffusion rate at the solid-liquid interface, resulting in limited detection sensitivity and accuracy, and the one-dimensional TiO2 nanowire array has insufficient light capture capability.
A three-dimensional TiO2 nanowire array was constructed by vertically growing the first and second TiO2 nanowires on a conductive substrate to form hydrophobic and hydrophilic surfaces, load oxidase, enhance light capture ability and oxygen transmission channels, and realize three-phase interfacial reaction.
The detection sensitivity and charge separation efficiency of the photoelectrochemical enzyme biosensor are improved, efficient enzyme catalysis and photoelectrocatalytic cascade reactions are achieved, the detection range is expanded and the detection sensitivity is improved.
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Figure CN120801459A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to a three-phase interface biological enzyme photoelectrode, a construction method thereof and a biosensor, and belongs to the technical field of biosensors. BACKGROUND
[0002] With the rapid development of the national economy and society, people's quality of life has been greatly improved, but the incidence of some chronic diseases that threaten human health, such as cardiovascular and cerebrovascular diseases, diabetes, gout, etc., has shown a clear upward trend. Therefore, developing efficient biological detection technology is crucial for disease detection. Among the many sensing technologies, photoelectrochemical biological sensors use light excitation and electrical detection for sensing analysis, achieving complete separation of excitation and detection signals, and thus have high sensitivity and low detection limit.
[0003] In a photoelectrochemical enzyme biosensor using an oxidase as a biological recognition element, the oxidase catalytic reaction occurs at the solid-liquid interface. Due to the low concentration of dissolved oxygen in the test solution and the slow diffusion rate, the regeneration process of the oxidase during the enzyme catalytic reaction is limited, which restricts the kinetics of the oxidase catalytic reaction, resulting in limited detection linear range and accuracy of the photoelectrochemical enzyme biosensor. To address these issues, in existing research work, an enzyme electrode with a solid-liquid-gas three-phase reaction interface is introduced into the photoelectrochemical enzyme biosensor, so that the oxygen required for the oxidase catalytic reaction can be directly supplied from the gas phase to the catalytic reaction interface, greatly improving the kinetics of the oxidase catalytic reaction and improving the sensing performance of the enzyme biosensor.
[0004] The current three-phase interface enzyme electrode based on one-dimensional TiO2 nanowire array effectively solves the bottleneck problem of limited oxygen diffusion kinetics in traditional photoelectrochemical biosensors through surface wettability regulation. However, the one-dimensional nanowire in this structure has insufficient light trapping ability, resulting in low density of photo-generated carriers. These factors together restrict the detection sensitivity of the photoelectrochemical sensor, limiting its application in trace detection scenarios. SUMMARY
[0005] The present application proposes a three-phase interface biological enzyme photoelectrode, a construction method thereof and a biosensor, which is based on TiO2 nanowire array construction and improves detection sensitivity by enhancing the light trapping ability of TiO2 nanowire array.
[0006] The first aspect of the present application relates to a three-phase interface biological enzyme photoelectrode, comprising: a conductive substrate, first TiO2 nanowires and second TiO2 nanowires.
[0007] The first TiO2 nanowire vertical (thickness direction of the conductive substrate) array is arranged on the conductive substrate, and the second TiO2 nanowire vertical array is arranged on the first TiO2 nanowire, forming a three-dimensional TiO2 nanowire array.
[0008] The three-dimensional TiO2 nanowire array has a lower hydrophobic surface and an upper hydrophilic surface, and the hydrophilic surface is loaded with oxidase.
[0009] The second aspect of the present application relates to a method for constructing a three-phase interface bioenzyme photoelectrode, comprising the following steps:
[0010] S1, first, a layer of TiO2 nanoparticles is modified on the surface of the conductive substrate; then, the seed crystal is grown vertically (thickness direction of the conductive substrate) on the surface of the conductive substrate by the first hydrothermal reaction, and the first TiO2 nanowire is obtained by annealing treatment, and the first TiO2 nanowire array is obtained by the first TiO2 nanowire; then, the second TiO2 nanowire is grown on the first TiO2 nanowire by the second hydrothermal reaction, and the second TiO2 nanowire array is obtained by annealing treatment; the second TiO2 nanowire is arranged vertically on the first TiO2 nanowire, and the three-dimensional TiO2 nanowire array is formed;
[0011] S2, the three-dimensional TiO2 nanowire array is immersed in a solution containing a low surface energy substance, and solidified treatment is carried out, so that the low surface energy substance is attached to the surface of the TiO2 nanowire, and the super-hydrophobic nanowire array is obtained;
[0012] S3, the hydrophobic layer on the upper surface of the super-hydrophobic nanowire array is stripped by using surface plasmon cleaning technology, and the upper hydrophilic surface is formed; then, the oxidase is loaded on the hydrophilic surface; after drying, the three-phase interface bioenzyme photoelectrode is obtained.
[0013] The third aspect of the present application relates to a biosensor, comprising the above-mentioned three-phase interface bioenzyme photoelectrode, reference electrode and counter electrode.
[0014] Compared with the prior art, the present application has the following technical effects:
[0015] The nanowires are kept separate from each other in the three-phase interface biological enzyme photoelectrode, thus forming certain gaps, which provide oxygen transmission channels for enzyme catalytic reaction; meanwhile, the three-dimensional TiO2 nanowire array formed by the second TiO2 nanowires arranged in a circumferential array around the first TiO2 nanowires and arranged in a length direction array around the first TiO2 nanowires has nanowires that are relatively dense in a unit space, and obtains high efficient light capturing capacity and fast electron transmission channels, which can significantly improve the carrier density and charge separation efficiency; thus, the three-phase interface photoelectrochemical enzyme biosensor of the application can realize synchronous improvement of the enzyme catalysis and photoelectrocatalysis cascade reaction efficiency, and thus realize efficient detection. BRIEF DESCRIPTION OF DRAWINGS
[0016] Figure 1 The scanning electron microscope picture of the one-dimensional TiO2 nanowire array in Example 1 and Comparative Example 1;
[0017] Figure 2 The scanning electron microscope picture of the three-dimensional TiO2 nanowire array in Example 1;
[0018] Figure 3 The contact angle picture of the super-hydrophobic nanowire array in Example 1;
[0019] Figure 4 The photocurrent response curve of the three-phase interface photoelectrochemical enzyme biosensor in Example 1 when detecting glucose;
[0020] Figure 5 The photocurrent response curve of the three-phase interface photoelectrochemical enzyme biosensor in Example 2 when detecting glucose;
[0021] Figure 6 The photocurrent response curve of the three-phase interface photoelectrochemical enzyme biosensor in Example 3 when detecting glucose;
[0022] Figure 7 The photocurrent response curve of the three-phase interface photoelectrochemical enzyme biosensor in Comparative Example 1 when detecting glucose;
[0023] Figure 8 The photocurrent response curve of the solid-liquid two-phase interface photoelectrochemical enzyme biosensor in Comparative Example 2 when detecting glucose. DETAILED DESCRIPTION
[0024] The embodiments of the application will be described in detail below with reference to the accompanying drawings. The experimental methods not specified in the examples are carried out according to the conventional methods and conditions.
[0025] The example of the application relates to a construction method of a three-phase interface biological enzyme photoelectrode, comprising the following steps:
[0026] S1, a preparation step of the three-dimensional TiO2 nanowire array: first, a layer of TiO2 nanoparticles is modified on the surface of the FTO conductive substrate; then, based on the TiO2 nanoparticles (as seed crystals), a first TiO2 nanowire is vertically grown on the surface of the FTO conductive substrate through a first hydrothermal reaction, and then annealing treatment is performed to obtain a first TiO2 nanowire array composed of the first TiO2 nanowire; then, a second TiO2 nanowire is secondarily grown on the first TiO2 nanowire through a second hydrothermal reaction, and then annealing treatment is performed to obtain a second TiO2 nanowire array composed of the second TiO2 nanowire, the second TiO2 nanowire being vertically arranged on the first TiO2 nanowire to form the three-dimensional TiO2 nanowire array;
[0027] S2, a hydrophobic treatment step: the three-dimensional TiO2 nanowire array is immersed in a solution containing a low-surface-energy substance, and solidification treatment is performed to make the low-surface-energy substance adhere to the surface of the TiO2 nanowire, thereby obtaining a super-hydrophobic nanowire array;
[0028] S3, an oxidase loading treatment step: a surface plasmon cleaning technology is used to strip the hydrophobic layer on the upper surface of the super-hydrophobic nanowire array to form an upper hydrophilic surface; then, an oxidase is loaded on the hydrophilic surface; after drying, a three-phase interface bio-enzyme photoelectrode is obtained.
[0029] For some specific embodiments, the layer of TiO2 nanoparticles has a thickness of 20-80 nm, for example, 20 nm, 30 nm, 40 nm, 50 nm, 70 nm, 80 nm, etc., and the layer thickness can be controlled by adjusting the concentration of tetrabutyl titanate.
[0030] For some specific embodiments, the specific operation of modifying a layer of TiO2 nanoparticles on the surface of the FTO conductive substrate is as follows: a precursor solution is configured, the solution composition being solute ethanol, tetrabutyl titanate, diethanolamine, and solvent water, the solute concentrations being 12.6-16.9 mol / L, 0.30-0.45 mol / L, and 0.26-0.51 mol / L, respectively; the FTO conductive substrate is immersed in the precursor solution, and then pulled out, so that the surface of the FTO conductive glass is covered with a layer of solution; after natural drying, calcination is performed, for example, the FTO conductive substrate is placed in a muffle furnace for calcination at 550℃ for 30 min, thereby obtaining TiO2 nanoparticles.
[0031] For example, the concentration of the solute ethanol can be 12.6 mol / L, 13 mol / L, 13.5 mol / L, 14 mol / L, 14.5 mol / L, 15 mol / L, 15.5 mol / L, 16 mol / L, 16.5 mol / L, 16.9 mol / L, etc.
[0032] For example, the concentration of the solute tetrabutyl titanate can be 0.30 mol / L, 0.35 mol / L, 0.40 mol / L, 0.45 mol / L, etc.
[0033] For example, the concentration of the solute diethanolamine can be 0.26 mol / L, 0.30 mol / L, 0.35 mol / L, 0.40 mol / L, 0.45 mol / L, 0.50 mol / L, 0.51 mol / L, etc.
[0034] For some specific embodiments, the length of the first TiO2 nanowire is 3-8 μm, and the diameter is 80-200 nm; the length of the second TiO2 nanowire is 50-150 nm, and the diameter is 30-90 nm.
[0035] For example, the length of the first TiO2 nanowire can be 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, etc., and the diameter of the first TiO2 nanowire can be 80 nm, 90 nm, 100 nm, 110 nm, 120 nm, 130 nm, 140 nm, 150 nm, 160 nm, 170 nm, 180 nm, 190 nm, 200 nm, etc.
[0036] For example, the length of the second TiO2 nanowire can be 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, 100 nm, 110 nm, 120 nm, 130 nm, 140 nm, 150 nm, etc., and the diameter of the second TiO2 nanowire can be 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, etc.
[0037] For some specific embodiments, the FTO conductive substrate is pretreated, and the pretreatment includes ultrasonic cleaning in deionized water, a mixture of ethanol and acetone, and deionized water in sequence, and then dried with nitrogen. Preferably, the cleaning time is 5 min each.
[0038] For some specific embodiments, the first hydrothermal reaction uses a mixed solution of solute tetrabutyl titanate, butanone, ethanol, HCl, and solvent water, and the solute concentrations are 0.13-0.29 mol / L, 1.11-1.59 mol / L, 0.21-0.28 mol / L, and 7.10-10.66 mol / L in sequence; the reaction temperature is 165-185°C, and the reaction time is 2.5-6.0 h.
[0039] For example, the concentration of the solute tetrabutyl titanate can be 0.13 mol / L, 0.15 mol / L, 0.20 mol / L, 0.25 mol / L, 0.29 mol / L, etc.
[0040] The concentration of butanone can be 1.11 mol / L, 1.15 mol / L, 1.20 mol / L, 1.25 mol / L, 1.30 mol / L, 1.35 mol / L, 1.40 mol / L, 1.45 mol / L, 1.50 mol / L, 1.55 mol / L, 1.59 mol / L, etc.
[0041] The concentration of ethanol can be 0.21 mol / L, 0.22 mol / L, 0.23 mol / L, 0.24 mol / L, 0.25 mol / L, 0.26 mol / L, 0.27 mol / L, 0.28 mol / L, etc.
[0042] The concentration of HCl can be 7.10 mol / L, 7.50 mol / L, 8.00 mol / L, 8.50 mol / L, 9.00 mol / L, 9.50 mol / L, 10.00 mol / L, 10.50 mol / L, 10.66 mol / L, etc.
[0043] For example, the reaction temperature of the first hydrothermal reaction can be 165℃, 170℃, 175℃, 180℃, 185℃, etc., and the reaction time can be 2.5h, 3.0h, 3.5h, 4.0h, 4.5h, 5.0h, 5.5h, 6.0h, etc.
[0044] For some specific embodiments, the second hydrothermal reaction uses a mixed solution of solute titanium trichloride, HCl and solvent water, and the concentrations of solute titanium trichloride and HCl are 0.008-0.020 mol / L and 0.12-0.24 mol / L, respectively; the reaction temperature is 75-95℃, and the reaction time is 1.5-3h.
[0045] For example, the concentration of titanium trichloride can be 0.008 mol / L, 0.009 mol / L, 0.010 mol / L, 0.011 mol / L, 0.012 mol / L, 0.013 mol / L, 0.014 mol / L, 0.015 mol / L, 0.016 mol / L, 0.017 mol / L, 0.018 mol / L, 0.019 mol / L, 0.020 mol / L, etc.
[0046] The concentration of HCl can be 0.12 mol / L, 0.15 mol / L, 0.17 mol / L, 0.19 mol / L, 0.20 mol / L, 0.22 mol / L, 0.23 mol / L, 0.24 mol / L, etc.
[0047] For example, the reaction temperature of the second hydrothermal reaction can be 75℃, 80℃, 85℃, 90℃, 95℃, etc., and the reaction time can be 1.5h, 2.0h, 2.5h, 3.0h, etc.
[0048] For some specific embodiments, the low surface energy substance in the solution containing low surface energy substance is at least one of methyltrimethoxysilane, polytetrafluoroethylene, perfluorooctyltrichlorosilane, polydimethylsiloxane, and polymethylhydrosiloxane, and the concentration of the low surface energy substance is 0.00135-0.0054 mol / L; for example, the concentration can be 0.00135 mol / L, 0.0015 mol / L, 0.0020 mol / L, 0.0025 mol / L, 0.0030 mol / L, 0.0035 mol / L, 0.0040 mol / L, 0.0045 mol / L, 0.0050 mol / L, 0.0054 mol / L, etc. The curing treatment can be heat curing or ultraviolet light curing.
[0049] For some specific embodiments, in step S2, the infiltration time is 1-2h; for example, the infiltration time can be 1.0h, 1.5h, 2.0h, etc.
[0050] For some specific embodiments, in step S2, the heating temperature is 100-120℃, and the heating time is 0.5-2h; for example, the heating temperature can be 100℃, 105℃, 110℃, 115℃, 120℃, etc., and the heating time can be 0.5h, 1.0h, 1.5h, 2.0h, etc.
[0051] For some specific embodiments, in step S3, the power of the plasma cleaning is 50-200W, and the cleaning time is 5-20s; for example, the power of the plasma cleaning is 50W, 100W, 150W, 200W, etc., and the cleaning time can be 5s, 10s, 15s, 20s, etc.
[0052] For some specific embodiments, in the direction perpendicular to the conductive substrate (substrate thickness direction), the height dimension of the upper hydrophilic surface is 500nm-1μm; for example, the height can be 500nm, 600nm, 700nm, 800nm, 900nm, 1μm, etc.
[0053] For some specific embodiments, in step S3, the oxidase mixed solution is a mixed solution of an oxidase aqueous solution and a Nafion aqueous solution, the concentration of the oxidase in the oxidase aqueous solution is 10-40mg / mL, the mass percentage of Nafion in the Nafion aqueous solution is 5-10wt%, and the oxidase includes at least one of glucose oxidase, ethanol oxidase, choline oxidase, and lactic acid oxidase.
[0054] For example, the concentration of oxidase is 10 mg / mL, 15 mg / mL, 20 mg / mL, 25 mg / mL, 30 mg / mL, 35 mg / mL, 40 mg / mL, etc.; the mass percentage concentration of Nafion is 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt%, etc.
[0055] For some specific embodiments, a three-phase enzyme bio-photoelectrode is used as a working electrode, a saturated silver / silver chloride electrode or a saturated calomel electrode is used as a reference electrode, a platinum wire or a platinum sheet is used as a counter electrode, and a phosphate solution is used as an electrolyte solution, and then they are assembled together to obtain a biosensor.
[0056] Example 1
[0057] The process of constructing the biosensor in this example is as follows:
[0058] Step one, a 2.5 cm x 1.5 cm size FTO conductive glass is sequentially placed in deionized water, ethanol / acetone mixture, deionized water and ultrasonically cleaned for 5 min, and then dried with nitrogen for standby;
[0059] Step two, a precursor solution is prepared, the precursor solution is composed of 14.3 mol / L ethanol, 0.36 mol / L tetrabutyl titanate, 0.35 mol / L diethanolamine and water; the FTO conductive glass is immersed in the precursor solution, then taken out, naturally dried and placed in a muffle furnace for calcination at 550℃ for 30 min, to form a layer of TiO2 nanoparticles with a thickness of 40 nm on the surface of the FTO conductive glass;
[0060] Step three, the TiO2 nanoparticles are used as seeds and placed in a mixed solution of water composed of 0.26 mol / L tetrabutyl titanate, 1.44 mol / L butanone, 0.28 mol / L ethanol and 8.87 mol / L HCl, and reacted at 180℃ for 6 h, and then calcined at 400℃ for 1 h after the reaction is completed, to obtain first TiO2 nanowires with an average length and diameter of 5 μm and 80 nm, which constitute a first TiO2 nanowire array;
[0061] Step four, the first TiO2 nanowire array is placed in a mixed solution composed of deionized water, 0.22 mol / L HCl and 0.01 mol / L titanium trichloride, and reacted at 80℃ for 1.5 h, and then washed, dried and calcined at 400℃ for 1 h after the reaction is completed, at this time, second TiO2 nanowires with an average length and diameter of 120 nm and 50 nm are formed on the first TiO2 nanowires, and constitute a three-dimensional TiO2 nanowire array as shown in Figure 2
[0062] Step five, the three-dimensional TiO2 nanowire array is immersed in a toluene solution of perfluorooctyltrichlorosilane with a molar concentration of 0.0027 mol / L for 2 h, and then taken out and cleaned with ethanol, and then heated at 120°C for 2 h to obtain a super-hydrophobic nanowire array, the contact angle of which is shown in Figure 3 ;
[0063] Step six, the FTO conductive glass with the super-hydrophobic nanowire array is placed in a plasma cleaning machine and treated at a power of 150 W for 5 s to make the upper part of the nanowire array hydrophilic and the lower part remain hydrophobic, and the height dimension of the upper hydrophilic surface is 1 μm; finally, 50 μL of a mixed solution of oxidase (a mixed solution of 45 μL of a 20 mg / mL glucose oxidase solution and 5 μL of a 5% Nafion aqueous solution) is dropped on the nanowire array, and a three-phase interface bio-enzyme photoelectrode based on a three-dimensional TiO2 nanowire array is obtained after natural drying.
[0064] Step seven, a three-phase interface photoelectrochemical enzyme biosensor is assembled by using a three-electrode mode, taking the three-phase interface bio-enzyme photoelectrode as a working electrode, Ag / AgCl as a reference electrode, a platinum wire as a counter electrode, and a phosphate solution as an electrolyte solution.
[0065] Example 2
[0066] Compared with Example 1, the difference of the present example is that:
[0067] 1. The content of butanone in Step three is 1.52 mol / L; and the reaction is carried out at 180°C for 4 h.
[0068] 2. The reaction in Step four is carried out at 80°C for 1 h.
[0069] Example 3
[0070] Compared with Example 1, the difference of the present example is that:
[0071] Step five is different in the process of hydrophobic treatment, specifically, 20 μL of methyl-terminated polymethylhydrogenosiloxane is dropped on the surface of the prepared three-dimensional TiO2 nanowire array, and irradiated with 365 nm ultraviolet light (1 mW / cm 2 ) for 10 min, and then taken out and cleaned with cyclohexane, and then dried to obtain a super-hydrophobic nanowire array.
[0072] Comparative Example 1
[0073] Compared with Example 1, the difference of the present example is that:
[0074] No second TiO2 nanowire is constructed, and only the first TiO2 nanowire array shown in Figure 1 is subjected to hydrophobic treatment and oxidase loading treatment.
[0075] Comparative Example 2
[0076] The difference between the comparative example and Example 1 is only that:
[0077] No hydrophobic treatment is performed; and finally a solid-liquid two-phase photoelectrochemical enzyme biosensor is prepared.
[0078] The photoelectrochemical enzyme biosensors prepared in the above examples and comparative examples are subjected to photoelectric current response test, specifically, 365nm laser is used as excitation light source, and the irradiation intensity of light on the working electrode is kept at 1mW / cm 2 The photoelectric current response of different concentrations of the to-be-detected substance in electrolyte is investigated by chronoamperometry; the test results are shown in Table 1. Figures 4-8 As can be seen from Table 1, the upper limit of the three-dimensional TiO2 nanowire array prepared in the examples of the present application for the to-be-detected substance detection can reach 100mM, and the detection sensitivity is more than 2 times higher than that of the three-phase interface photoelectrochemical enzyme biosensor based on one-dimensional TiO2 nanowire array, which not only has efficient light capturing capacity, but also provides a fast electron transport channel, and the synergistic effect of the two significantly improves the charge separation efficiency, so that the constructed sensor has the characteristics of wide linear detection range, high detection sensitivity, high stability and the like.
[0079] It should be emphasized that: the above is only the preferred embodiment of the present application, and does not limit the present application in any form, any simple modification, equivalent change and modification of the above examples according to the technical essence of the present application still belong to the scope of the technical solutions of the present application.
Claims
1. A three-phase interface bioenzyme photoelectrode, characterized in that: include: a conductive substrate, a first TiO2 nanowire and a second TiO2 nanowire; A first TiO2 nanowire vertical array is disposed on a conductive substrate, and a second TiO2 nanowire vertical array is disposed on the first TiO2 nanowire to form a three-dimensional TiO2 nanowire array; The three-dimensional TiO2 nanowire array has a lower hydrophobic surface and an upper hydrophilic surface, and the hydrophilic surface is loaded with oxidase.
2. The three-phase interface bioenzyme photoelectrode according to claim 1, characterized in that: The length of the first TiO2 nanowire is 3 to 8 μm and the diameter is 80 to 200 nm; the length of the second TiO2 nanowire is 50 to 150 nm and the diameter is 30 to 90 nm; Preferably, along a direction perpendicular to the conductive substrate, the height of the upper hydrophilic surface is 500 nm to 1 μm.
3. The three-phase interface bioenzyme photoelectrode according to claim 1, characterized in that: The oxidase includes at least one of glucose oxidase, ethanol oxidase, choline oxidase and lactate oxidase.
4. A method for constructing a three-phase interface bioenzyme photoelectrode, characterized in that: The following steps are involved: S1, first, modifying a layer of TiO2 nanoparticles on the surface of a conductive substrate; then, using the TiO2 nanoparticles as seeds, vertically growing first TiO2 nanowires from the seeds on the surface of the conductive substrate through a first hydrothermal reaction, followed by annealing, thereby obtaining a first TiO2 nanowire array composed of the first TiO2 nanowires; then, secondary growing of second TiO2 nanowires on the first TiO2 nanowires through a second hydrothermal reaction, followed by annealing, thereby obtaining a second TiO2 nanowire array composed of the second TiO2 nanowires; the second TiO2 nanowires are vertically arranged on the first TiO2 nanowires to form a three-dimensional TiO2 nanowire array; S2, immersing the three-dimensional TiO2 nanowire array in a solution containing a low surface energy substance, and curing the solution to allow the low surface energy substance to adhere to the surface of the TiO2 nanowires, thereby obtaining a superhydrophobic nanowire array; S3, using surface plasma cleaning technology, the hydrophobic layer on the upper surface of the super-hydrophobic nanowire array is peeled off to form an upper hydrophilic surface; then, oxidase is loaded on the hydrophilic surface; after drying, a three-phase interface bioenzyme photoelectrode is obtained.
5. The construction method according to claim 4, characterized in that: The layer thickness of the TiO2 nanoparticles is 20 to 80 nm; Preferably, the specific operation of modifying a layer of TiO2 nanoparticles on the surface of the conductive substrate is: preparing a precursor solution, the solution composition is solute ethanol, tetrabutyl titanate, diethanolamine and solvent water, and the solute concentrations are 12.6~16.9mol / L, 0.30~0.45mol / L and 0.26~0.51mol / L respectively; immersing the conductive substrate in the precursor solution, and then pulling it out so that the surface of the conductive glass is covered with a layer of solution, and calcining it after natural drying to obtain TiO2 nanoparticles.
6. The construction method according to claim 4, characterized in that: The first hydrothermal reaction uses a mixed solution of tetrabutyl titanate, butanone, ethanol, HCl and solvent water, with solute concentrations of 0.13-0.29 mol / L, 1.11-1.59 mol / L, 0.21-0.28 mol / L and 7.10-10.66 mol / L, respectively; the reaction temperature is 165-185°C, and the reaction time is 2.5-6.0 h; The second hydrothermal reaction uses a mixed solution of titanium trichloride, HCl and water, with the concentration of titanium trichloride being 0.008-0.020 mol / L and the concentration of HCl being 0.12-0.24 mol / L; the reaction temperature being 75-95° C., and the reaction time being 1.5-3 h.
7. The construction method according to claim 4, characterized in that: The low surface energy substance in the solution containing the low surface energy substance is at least one of methyltrimethoxysilane, polytetrafluoroethylene, perfluorooctyltrichlorosilane, polydimethylsiloxane, and polymethylhydrogensiloxane, and the concentration of the low surface energy substance is 0.00135 to 0.0054 mol / L; Preferably, the immersion time is 1 to 2 hours; Preferably, the heating temperature is 100-120° C., and the heating time is 0.5-2 h.
8. The construction method according to claim 4, characterized in that: In step S3 , the power of plasma cleaning is 50 to 200 W, and the cleaning time is 5 to 20 seconds.
9. The construction method according to claim 4, wherein: In step S3, loading the oxidase on the hydrophilic surface refers to dropping the oxidase mixed solution onto the nanowire array; the oxidase mixed solution is a mixed solution of an oxidase aqueous solution and a Nafion aqueous solution, the concentration of the oxidase in the oxidase aqueous solution is 10 to 40 mg / mL, the mass percentage of Nafion in the Nafion aqueous solution is 5 to 10 wt%, and the oxidase includes at least one of glucose oxidase, ethanol oxidase, choline oxidase, and lactate oxidase.
10. A biosensor, characterized in that: include: The three-phase interface bioenzyme photoelectrode, reference electrode and counter electrode according to any one of claims 1 to 3; Preferably, a saturated silver / silver chloride electrode or a saturated calomel electrode is used as a reference electrode, and a platinum wire or platinum sheet is used as a counter electrode.