CN106053573A - Preparation method of electrochemical sensor based on loaded bi-metal co-doped nano composite material - Google Patents

Abstract

The invention discloses a preparation method of an electrochemical sensor constructed on the basis of a nano functional material and belongs to the technical field of novel nano functional materials and biosensors. The preparation method includes: preparing a novel two-dimensional nano electrode material-the loaded bi-metal co-doped nano composite material FeCo-TiO2/MoS2, namely a two-dimensional nano composite material with an iron-cobalt co-doped titanium dioxide nano square block composited with molybdenum disulfide in situ; utilizing high biocompatibility and large specific surface area of the material to load a clenbuterol antibody; during detection, due to the fact that iron-cobalt co-doped titanium dioxide can catalyze hydrogen peroxide to generate O2 in situ to generate electrochemical signals, utilizing influence of specific quantitative combining of the antibody and antigen on electron transmission capability to correspondingly lower current strength; finally realizing construction of a biosensor adopting a mark-free electrochemical method to detect clenbuterol.

Description

A kind of electrochemical sensor based on load type double-metal co-doped nano composite Preparation method

Technical field

The present invention relates to the preparation method of a kind of electrochemical sensor built based on nano-functional material.Belong to Performances of Novel Nano-Porous Rice functional material and biosensor technology field.

Background technology

Clenbuterol, i.e. clenobuterol hydrochloride, owing to there being significant nutrition " redistribution effects " to promote animal body egg White matter deposition, promotion steatolysis suppression lipidosis, can significantly improve the lean meat percentage of trunk, increase weight and improve food conversion Rate.Therefore, it is also referred to as clenbuterol hydrochloride in China, is once used as the growth promoter of poultry, the feed additives such as cattle, sheep, fowl, pig. But owing to Clenbuterol is excessive to human health damage, thus result in potential safety hazard, also thus disabled in the whole world.

At present, the method for detection Clenbuterol mainly has chromatography, mass spectrography etc..This type of method instrument is valuable, operation is multiple Miscellaneous, laboratory personnel just can detect after needing professional training.Therefore, R&D costs are low, detect fast, highly sensitive, specificity Strong Clenbuterol sensor is significant.

Electrochemica biological sensor is widely used in facing due to advantages such as it are highly sensitive, specificity is good, easy and simple to handle The fields such as bed diagnosis, pharmaceutical analysis, environmental monitoring.The most especially more with the research of unmarked electrochemical immunosensor, it is crucial Technology be to improve the fixed amount of modified electrode antagonist and to the test signal response speed of end liquid and size.Titanium dioxide is A kind of photocatalyst material being most widely used, simultaneously because good biocompatibility, is also commonly used as electrode matrix material.By Can expose more high miller index surface in sheet-like titanium dioxide nanomaterial, have higher catalysis activity, titanium dioxide is received Rice sheet has ratio nanoparticle preferably application prospect, and the research for titanium dioxide nanoplate also receives much concern.But, dioxy The sensitivity that change titanium poorly conductive also limit the electrochemical sensor built by single titanium dioxide nano material is the highest, It is unfavorable for actual application.Semiconductor nano material is modified or is combined special nano material, on the one hand adds electrode ratio Surface area, strengthens electrodes conduct ability, and on the other hand the two can produce concerted catalysis effect, and bigger enhancing is to hydrogen peroxide Solution H₂O₂Catalytic response speed and current responsing signal size, be greatly improved detection sensitivity.Therefore, design, prepare height Effect, stable titanium dioxide nanoplate and trim thereof are the key technologies preparing electrochemical sensor.

(chemical formula is MoS to molybdenum bisuphide₂) nano material, there is two-dimensional layered structure, be most widely used solid profit One of lubrication prescription.Lamellar two-dimension nano materials after its stripping, is the semiconductor nano material of excellent performance, except having big ratio Surface area, can improve load capacity as catalyst and the carrier of biological antibody, also has simultaneously as promoter excellent Electron transmission performance.

At present, most synthesizing mean be all be separately synthesized after, then catalyst is combined with carrier, process is numerous Trivial, productivity is the highest.Therefore, for In-situ reaction preparation, there is the two dimensional nano electrodes material of good electric chemical property to have extensively Application prospect and important scientific meaning.

Summary of the invention

It is an object of the invention to provide a kind of prepare simple, highly sensitive, detection quickly, the electrochemical student of high specificity The preparation method of thing sensor, prepared sensor, can be used for quick, the Sensitive Detection of Clenbuterol.Based on this purpose, this First invention is prepared for a kind of New Two Dimensional nano-electrode material load type double-metal co-doped nano composite FeCo- TiO₂/MoS₂, i.e. ferrum, the two-dimensional nano composite of cobalt codoping titanium dioxide nano square In-situ reaction molybdenum bisuphide, utilize The good biocompatibility of this material and big specific surface area, antibody of clenbuteral in load, when detecting, due to Ferrum, cobalt codope titanium dioxide can be with catalyzing hydrogen peroxide in-situ preparation O₂, produce electrochemical signals, recycling antibody and antigen Specific quantification combine impact on electron transport ability so that current intensity reduces accordingly, finally achieves employing without mark The structure of the biosensor of the electrochemical method detection Clenbuterol of note.

The technical solution used in the present invention is as follows:

1. a preparation method for electrochemical sensor based on load type double-metal co-doped nano composite, its feature Be described electrochemical sensor by working electrode, load type double-metal co-doped nano composite, antibody of clenbuteral, Bovine serum albumin forms；Described load type double-metal co-doped nano composite is that ferrum, cobalt codope titanium dioxide are received Rice square and the two-dimensional nano composite FeCo-TiO of molybdenum bisuphide In-situ reaction₂/MoS₂；

It is characterized in that, described preparation method includes following preparation process:

A. FeCo-TiO is prepared₂/MoS₂；

B. electrochemical sensor is prepared；

Wherein, step a prepares FeCo-TiO₂/MoS₂Concretely comprise the following steps:

(1) take 0.6 g molybdenum disulfide powder, 0.2 ~ 2.0 mmol iron salt and 0.2 ~ 2.0 mmol cobalt salt jointly join 3 ~ In 10 mL n-butyllithium solutions, at nitrogen protection and 30 ~ 60 DEG C, stir 12 ~ 48 hours, obtain reacted molten Liquid；

(2) utilize reacted solution in non-polar solven washing step (1), at 30 ~ 60 DEG C, then carry out water bath sonicator Process, after having processed, the solution after recycling non-polar solven carrying out washing treatment, vacuum drying, obtain two sulfur of ferrum, cobalt intercalation altogether Change molybdenum nano material；

(3) the molybdenum disulfide nano material taking the prepared ferrum of 10 ~ 500 mg steps (2), cobalt intercalation altogether joins 5 mL metatitanic acids In four butyl esters, after stirring 1 hour, it is slowly added to 0.5 ~ 0.8 mL Fluohydric acid. while stirring, then instead at 160 ~ 200 DEG C Answer in still and react 18 ~ 24 hours；

(4) by the product of step (3) gained, after ultra-pure water and dehydrated alcohol centrifuge washing three times, at 50 DEG C, vacuum is done Dry, i.e. prepare FeCo-TiO₂/MoS₂；

Described n-butyllithium solution is the hexane solution of n-BuLi, and concentration is 1.6 mol/L；

Described iron salt is selected from one of following: iron sulfate, iron chloride, ferric nitrate, ferric acetate, organoiron compound；

Described cobalt salt is selected from one of following: cobaltous sulfate, cobaltous chloride, cobalt nitrate, cobalt acetate, organic cobalt compounds；

Described non-polar solven is selected from one of following: hexane, hexamethylene, carbon tetrachloride, benzene, toluene；

Described water bath sonicator processes, and the process time is 1 hour；

Step b prepares concretely comprising the following steps of electrochemical sensor:

(1) with ITO electro-conductive glass as working electrode, at the FeCo-TiO of electrode surface drop coating 8 ~ 12 L₂/MoS₂Colloidal sol, room temperature Under dry；

(2) the electrode buffer solution PBS that will obtain in step (1), continues at electrode surface drop coating 8 ~ 12 L 10 The antibody of clenbuteral solution of g/mL, preserves in 4 DEG C of refrigerators and dries；

(3) the electrode PBS that will obtain in step (2), continuing in electrode surface drop coating 8 ~ 12 L concentration is 100 g/ The bovine serum albumin solution of mL, preserves in 4 DEG C of refrigerators and dries；

(4) the electrode PBS that will obtain in step (3), preserves after drying in 4 DEG C of refrigerators, i.e. prepares electrochemistry and passes Sensor；

Described FeCo-TiO₂/MoS₂Colloidal sol is by the FeCo-TiO of 50 mg₂/MoS₂Powder is dissolved in 10 mL ultra-pure waters, and The hydrosol prepared after ultrasonic 30 min；

Described PBS is the phosphate buffered solution of 10 mmol/L, and the pH value of described phosphate buffered solution is 7.4.

The application of the electrochemical sensor prepared by preparation method the most of the present invention, it is characterised in that include as follows Applying step:

A. standard solution preparation: prepare the Clenbuterol standard solution of one group of variable concentrations including blank standard specimen；

B. working electrode modify: by the electrochemical sensor prepared by preparation method as claimed in claim 1 be work electricity Pole, by the drop coating respectively of the Clenbuterol standard solution of the variable concentrations of preparation in step a to working electrode surface, 4 DEG C of refrigerators Middle preservation；

C. working curve is drawn: using saturated calomel electrode electrode as reference electrode, platinum electrode is as to electrode, with step b The working electrode composition three-electrode system modified, connects electrochemical workstation, successively adds 15 mL PBS in a cell H with 20 L 5 mol/L₂O₂；By the working electrode of chronoamperometry detection assembling to H₂O₂Response；Blank standard specimen Response current is designated asI ₀, the response current of the Clenbuterol standard solution containing variable concentrations is denoted asI _i, response current reduces Difference be ΔI = I ₀ -I _i, ΔIMass concentration with Clenbuterol standard solutionCBetween linear, draw ΔI-CWorking curve；

D. the detection of Clenbuterol: replace the Clenbuterol standard solution in step a with testing sample, according in step b and c Method detect, according to response electrical signal intensity reduce difference DELTAIAnd working curve, obtain gram human relations in testing sample The content of special sieve.

The useful achievement of the present invention

(1) electrochemical sensor of the present invention preparation is simple, easy to operate, it is achieved that quick, sensitive, the Gao Xuan to sample Selecting property detects, and low cost, can be applicable to portable inspectiont, has market development prospect；

(2) present invention uses the method for In-situ reaction to be prepared for New Two Dimensional nano-electrode material FeCo-TiO first₂/MoS₂, The method mainly has three advantages: one is, due to ferrum, the cobalt growth in situ on nano titania square jointly fully with Nano titania square contacts, and utilizes the metal surface plasma body effect of ferrum, cobalt, is effectively increased semiconductor substrate electronics Transmission capacity and catalysis activity, although solving, titanium dioxide nanoplate specific surface area is bigger and mesoporous characteristic is applicable to electrification Host material, but the technical problem that electro-chemical activity is the highest and current signal is unstable；Two are, due to molybdenum bisuphide lamellar The load characteristic of two-dimension nano materials and nano titania square thereon fully dispersed, greatly increases electron transmission Ability, solves titanium dioxide nanoplate poorly conductive and current responsing signal is weak and be unfavorable for preparing the skill of electrochemical sensor Art problem；Three are, due to ferrum, cobalt ion the most not only as intercalation material but also as reaction dopant material, finally use The method of In-situ reaction achieves one pot of preparation of this composite, not only saves time, spillage of material, and makes preparation Ferrum, the nano titania square of cobalt codope can preferably evenly spread on molybdenum bisuphide lamellar two-dimension nano materials Face.Therefore, effective preparation of this material, there is important scientific meaning and using value；

(3) present invention is first by FeCo-TiO₂/MoS₂It is applied in the preparation of electrochemica biological sensor, significantly improves electricity The strength and stability of stream signal, substantially increases the detection sensitivity of electrochemical sensor so that electrochemica biological sensor Achieve the application in real work；The application of this material, is also associated biomolecule sensor, such as Optical Electro-Chemistry sensor, electricity Cause chemiluminescence sensor etc. and provide Technical Reference, there is the most potential use value.

Detailed description of the invention

Embodiment 1 FeCo-TiO₂/MoS₂Preparation

(1) taking 0.6 g molybdenum disulfide powder, 0.2 mmol iron salt and 0.2 mmol cobalt salt, jointly to join 3mL n-BuLi molten In liquid, at nitrogen protection and 60 DEG C, stir 12 hours, obtain reacted solution；

(2) utilize reacted solution in non-polar solven washing step (1), at 60 DEG C, then carry out water bath sonicator process, After having processed, the solution after recycling non-polar solven carrying out washing treatment, vacuum drying, obtain the molybdenum bisuphide of ferrum, cobalt intercalation altogether Nano material；

(3) the molybdenum disulfide nano material taking the prepared ferrum of 500 mg steps (2), cobalt intercalation altogether joins 5 mL butyl titanates In, after stirring 1 hour, it is slowly added to 0.5 mL Fluohydric acid. while stirring, then reacts 18 hours in a kettle. at 160 DEG C；

(4) by the product of step (3) gained, after ultra-pure water and dehydrated alcohol centrifuge washing three times, at 50 DEG C, vacuum is done Dry, i.e. prepare FeCo-TiO₂/MoS₂；

Described n-butyllithium solution is the hexane solution of n-BuLi, and concentration is 1.6 mol/L；

Described iron salt is iron sulfate；

Described cobalt salt is cobaltous sulfate；

Described non-polar solven is hexane；

Described water bath sonicator processes, and the process time is 1 hour.

Embodiment 2 FeCo-TiO₂/MoS₂Preparation

(1) taking 0.6 g molybdenum disulfide powder, 1.0 mmol iron salt and 1.0 mmol cobalt salts, jointly to join 5 mL n-BuLis molten In liquid, at nitrogen protection and 30 DEG C, stir 24 hours, obtain reacted solution；

(2) utilize reacted solution in non-polar solven washing step (1), at 30 DEG C, then carry out water bath sonicator process, After having processed, the solution after recycling non-polar solven carrying out washing treatment, vacuum drying, obtain the molybdenum bisuphide of ferrum, cobalt intercalation altogether Nano material；

(3) the molybdenum disulfide nano material taking the prepared ferrum of 200 mg steps (2), cobalt intercalation altogether joins 5 mL butyl titanates In, after stirring 1 hour, it is slowly added to 0.6 mL Fluohydric acid. while stirring, then reacts 20 hours in a kettle. at 180 DEG C；

(4) by the product of step (3) gained, after ultra-pure water and dehydrated alcohol centrifuge washing three times, at 50 DEG C, vacuum is done Dry, i.e. prepare FeCo-TiO₂/MoS₂；

Described n-butyllithium solution is the hexane solution of n-BuLi, and concentration is 1.6 mol/L；

Described iron salt is iron chloride；

Described cobalt salt is cobaltous chloride；

Described non-polar solven is carbon tetrachloride；

Described water bath sonicator processes, and the process time is 1 hour.

Embodiment 3 FeCo-TiO₂/MoS₂Preparation

(1) take 0.6 g molybdenum disulfide powder, 2.0 mmol iron salt and 2.0 mmol cobalt salts and jointly join 10 mL n-BuLis In solution, at nitrogen protection and 50 DEG C, stir 48 hours, obtain reacted solution；

(2) utilize reacted solution in non-polar solven washing step (1), at 50 DEG C, then carry out water bath sonicator process, After having processed, the solution after recycling non-polar solven carrying out washing treatment, vacuum drying, obtain the molybdenum bisuphide of ferrum, cobalt intercalation altogether Nano material；

(3) the molybdenum disulfide nano material taking the prepared ferrum of 10 mg steps (2), cobalt intercalation altogether joins 5 mL butyl titanates In, after stirring 1 hour, it is slowly added to 0.8 mL Fluohydric acid. while stirring, then reacts 24 hours in a kettle. at 200 DEG C；

(4) by the product of step (3) gained, after ultra-pure water and dehydrated alcohol centrifuge washing three times, at 50 DEG C, vacuum is done Dry, i.e. prepare FeCo-TiO₂/MoS₂；

Described n-butyllithium solution is the hexane solution of n-BuLi, and concentration is 1.6 mol/L；

Described iron salt is ferric acetate；

Described cobalt salt is cobalt acetate；

Described non-polar solven is benzene；

Described water bath sonicator processes, and the process time is 1 hour.

The preparation method of embodiment 4 electrochemical sensor

(1) with glass-carbon electrode as working electrode, at the FeCo-TiO of electrode surface drop coating 8 L₂/MoS₂Colloidal sol, dries in the air under room temperature Dry；

(2) the electrode buffer solution PBS that will obtain in step (1), continues at electrode surface drop coating 8 L 10 g/mL Antibody of clenbuteral solution, 4 DEG C of refrigerators preserve and dry；

(3) the electrode PBS that will obtain in step (2), continuing in electrode surface drop coating 8 L concentration is 100 g/mL Bovine serum albumin solution, 4 DEG C of refrigerators preserve and dry；

(4) the electrode PBS that will obtain in step (3), preserves after drying in 4 DEG C of refrigerators, i.e. prepares electrochemistry and passes Sensor；

Described FeCo-TiO₂/MoS₂Colloidal sol is by the FeCo-TiO of 50 mg₂/MoS₂Powder is dissolved in 10 mL ultra-pure waters, and The hydrosol prepared after ultrasonic 30 min；

Described PBS is the phosphate buffered solution of 10mmol/L, and the pH value of described phosphate buffered solution is 7.4.

The preparation method of embodiment 5 electrochemical sensor

(1) with glass-carbon electrode as working electrode, at the FeCo-TiO of electrode surface drop coating 10 L₂/MoS₂Colloidal sol, dries in the air under room temperature Dry；

(2) the electrode buffer solution PBS that will obtain in step (1), continues at electrode surface drop coating 10 L 10 g/ The antibody of clenbuteral solution of mL, preserves in 4 DEG C of refrigerators and dries；

(3) the electrode PBS that will obtain in step (2), continuing in electrode surface drop coating 10 L concentration is 100 g/mL Bovine serum albumin solution, 4 DEG C of refrigerators preserve and dry；

(4) the electrode PBS that will obtain in step (3), preserves after drying in 4 DEG C of refrigerators, i.e. prepares electrochemistry and passes Sensor；

Described FeCo-TiO₂/MoS₂Colloidal sol is by the FeCo-TiO of 50 mg₂/MoS₂Powder is dissolved in 10 mL ultra-pure waters, and The hydrosol prepared after ultrasonic 30 min；

Described PBS is the phosphate buffered solution of 10 mmol/L, and the pH value of described phosphate buffered solution is 7.4.

The preparation method of embodiment 6 electrochemical sensor

(1) with glass-carbon electrode as working electrode, at the FeCo-TiO of electrode surface drop coating 12 L₂/MoS₂Colloidal sol, dries in the air under room temperature Dry；

(2) the electrode buffer solution PBS that will obtain in step (1), continues at electrode surface drop coating 12 L 10 g/ The antibody of clenbuteral solution of mL, preserves in 4 DEG C of refrigerators and dries；

(3) the electrode PBS that will obtain in step (2), continuing in electrode surface drop coating 12 L concentration is 100 g/mL Bovine serum albumin solution, 4 DEG C of refrigerators preserve and dry；

(4) the electrode PBS that will obtain in step (3), preserves after drying in 4 DEG C of refrigerators, i.e. prepares electrochemistry and passes Sensor；

Described FeCo-TiO₂/MoS₂Colloidal sol is by the FeCo-TiO of 50 mg₂/MoS₂Powder is dissolved in 10 mL ultra-pure waters, and The hydrosol prepared after ultrasonic 30 min；

Described PBS is the phosphate buffered solution of 10 mmol/L, and the pH value of described phosphate buffered solution is 7.4.

The electrochemical sensor of embodiment 7 embodiment 1 ~ 6 preparation, is applied to the detection of Clenbuterol, and step is as follows:

(1) standard solution preparation: prepare the Clenbuterol standard solution of one group of variable concentrations including blank standard specimen；

(2) working electrode modify: by the electrochemical sensor prepared by preparation method as claimed in claim 1 be work electricity Pole, by the drop coating respectively of the Clenbuterol standard solution of the variable concentrations of preparation in step (1) to working electrode surface, 4 DEG C of ice Case preserves；

(3) working curve is drawn: using saturated calomel electrode electrode as reference electrode, platinum electrode is as to electrode, with step b The working electrode composition three-electrode system modified, connects electrochemical workstation, successively adds 15 mL PBS in a cell H with 20 L 5 mol/L₂O₂；By the working electrode of chronoamperometry detection assembling to H₂O₂Response；Blank standard specimen Response current is designated asI ₀, the response current of the Clenbuterol standard solution containing variable concentrations is denoted asI _i, response current reduces Difference be ΔI = I ₀ -I _i, ΔIMass concentration with Clenbuterol standard solutionCBetween linear, draw ΔI-CWorking curve；The linear detection range of Clenbuterol is: 0.009 ~ 200 ng/mL, and detection is limited to: 3.0 pg/mL；

(4) detection of Clenbuterol: replace the Clenbuterol standard solution in step (1) with testing sample, according to step (2) and (3) method in detects, the difference DELTA reduced according to response electrical signal intensityIAnd working curve, obtain in testing sample The content of Clenbuterol.

Claims (4)

1. a preparation method for electrochemical sensor based on load type double-metal co-doped nano composite, its feature exists In described electrochemical sensor by working electrode, load type double-metal co-doped nano composite, antibody of clenbuteral, cattle Serum albumin forms；Described load type double-metal co-doped nano composite is ferrum, cobalt codoping titanium dioxide nano Square and the two-dimensional nano composite FeCo-TiO of molybdenum bisuphide In-situ reaction₂/MoS₂。

2. the preparation of electrochemical sensor based on load type double-metal co-doped nano composite as claimed in claim 1 Method, it is characterised in that described preparation method includes following two preparation process:

A. FeCo-TiO is prepared₂/MoS₂；

B. electrochemical sensor is prepared.

3. electrochemical sensor based on load type double-metal co-doped nano composite as described in claim 1 and 2 Preparation method, it is characterised in that described FeCo-TiO₂/MoS₂Concrete preparation process be:

(1) take 0.6 g molybdenum disulfide powder, 0.2 ~ 2.0 mmol iron salt and 0.2 ~ 2.0 mmol cobalt salt jointly join 3 ~ In 10 mL n-butyllithium solutions, at nitrogen protection and 30 ~ 60 DEG C, stir 12 ~ 48 hours, obtain reacted molten Liquid；

(2) utilize reacted solution in non-polar solven washing step (1), at 30 ~ 60 DEG C, then carry out water bath sonicator Process, after having processed, the solution after recycling non-polar solven carrying out washing treatment, vacuum drying, obtain two sulfur of ferrum, cobalt intercalation altogether Change molybdenum nano material；

(3) the molybdenum disulfide nano material taking the prepared ferrum of 10 ~ 500 mg steps (2), cobalt intercalation altogether joins 5 mL metatitanic acids In four butyl esters, after stirring 1 hour, it is slowly added to 0.5 ~ 0.8 mL Fluohydric acid. while stirring, then instead at 160 ~ 200 DEG C Answer in still and react 18 ~ 24 hours；

(4) by the product of step (3) gained, after ultra-pure water and dehydrated alcohol centrifuge washing three times, at 50 DEG C, vacuum is done Dry, i.e. prepare FeCo-TiO₂/MoS₂；

Described n-butyllithium solution is the hexane solution of n-BuLi, and concentration is 1.6 mol/L；

Described iron salt is selected from one of following: iron sulfate, iron chloride, ferric nitrate, ferric acetate, organoiron compound；

Described cobalt salt is selected from one of following: cobaltous sulfate, cobaltous chloride, cobalt nitrate, cobalt acetate, organic cobalt compounds；

Described non-polar solven is selected from one of following: hexane, hexamethylene, carbon tetrachloride, benzene, toluene；

Described water bath sonicator processes, and the process time is 1 hour.

4. electrochemical sensor based on load type double-metal co-doped nano composite as described in claim 1 and 2 Preparation method, it is characterised in that the concrete preparation process of described electrochemical sensor is:

(1) with glass-carbon electrode as working electrode, at the FeCo-TiO of electrode surface drop coating 8 ~ 12 L₂/MoS₂Colloidal sol, dries in the air under room temperature Dry；

(2) the electrode buffer solution PBS that will obtain in step (1), continues at electrode surface drop coating 8 ~ 12 L 10 The antibody of clenbuteral solution of g/mL, preserves in 4 DEG C of refrigerators and dries；

(3) the electrode PBS that will obtain in step (2), continuing in electrode surface drop coating 8 ~ 12 L concentration is 100 g/ The bovine serum albumin solution of mL, preserves in 4 DEG C of refrigerators and dries；

(4) the electrode PBS that will obtain in step (3), preserves after drying in 4 DEG C of refrigerators, i.e. prepares electrochemistry and passes Sensor；

Described FeCo-TiO₂/MoS₂Colloidal sol is by the FeCo-TiO of 50 mg₂/MoS₂Powder is dissolved in 10 mL ultra-pure waters, and The hydrosol prepared after ultrasonic 30 min；

Described PBS is the phosphate buffered solution of 10 mmol/L, and the pH value of described phosphate buffered solution is 7.4.