阅读说明：本技术 用于多巴胺、尿酸灵敏检测的Fe-PANI/Au修饰电极及其制备 (For dopamine, the Fe-PANI/Au modified electrode of uric acid Sensitive Detection and its preparation ) 是由 林玲玲 庄凰龙 游东宏 黄仁昆 王韬琛 于 2019-07-29 设计创作，主要内容包括：本发明提供了一种Fe-PANI/Au纳米复合材料修饰电极及其制备方法,所述方法包括：S1,将苯胺单体加入二氯甲烷溶液中超声使其均匀分散形成透明均一的有机相溶液；S2,在搅拌条件下往所述有机相溶液中依次缓慢加入氯金酸溶液、N-甲基吡咯烷酮水溶液与氯化铁溶液,室温下避光搅拌一段时间后静置；S3,将过硫酸铵-盐酸溶液缓慢加入步骤S2中反应溶液中,静置反应后用有机系滤膜过滤得到固体产物；S4,将所述固体产物清洗、过滤、自然晾干得到Fe-PANI/Au粉体；S5,将玻碳电极研磨抛光后备用；S6,取Fe-PANI/Au粉体超声分散于无水乙醇中,加入Nafion溶液超声分散使其形成均匀的悬浮液；S7,取悬浮液滴加到步骤S5抛光后的玻碳电极表面,静置待溶液挥发后得到Fe-PANI/Au修饰电极。(The present invention provides a kind of Fe-PANI/Au nanocomposite modified electrodes and preparation method thereof, which comprises S1, ultrasound in dichloromethane solution, which is added, in aniline monomer makes its evenly dispersed transparent uniform organic phase solution of formation；S2 is successively slowly added to chlorauric acid solution, N-Methyl pyrrolidone aqueous solution and ferric chloride solution into the organic phase solution under agitation, stands after being protected from light stirring a period of time at room temperature；Ammonium persulfate-hydrochloric acid solution is slowly added in step S2 in reaction solution by S3, is stood and is obtained solid product with organic system membrane filtration after reacting；Solid product cleaning, filtering, naturally dry are obtained Fe-PANI/Au powder by S4；S5, will be spare after glass-carbon electrode grinding and polishing；S6 takes Fe-PANI/Au powder ultrasonic disperse in dehydrated alcohol, and Nafion solution ultrasonic disperse is added and forms it into uniform suspension；S7, takes hanging drop to be added to the glassy carbon electrode surface after step S5 polishing, and standing obtains Fe-PANI/Au modified electrode after solution evaporation.)

1. a kind of preparation method of Fe-PANI/Au nanocomposite modified electrode, which comprises the following steps:

S1, ultrasound in 50mL dichloromethane solution, which is added, in 0.5mL aniline monomer its evenly dispersed formed transparent uniform Machine phase solution；

S2, the gold chloride for being successively slowly added to the 24.28mM of 0.103ml into the organic phase solution under agitation are molten Liquid, 50mL 0.2mol/L N-Methyl pyrrolidone aqueous solution and 0.05mL 0.5mol/L ferric chloride solution, at room temperature It is stood after being protected from light stirring a period of time；

0.3g ammonium persulfate is added in the hydrochloric acid solution of the 2mol/L of 8.6mL and forms ammonium persulfate-hydrochloric acid solution by S3, incited somebody to action Ammonium sulfate-hydrochloric acid solution is slowly added in step S2 in reaction solution, uses organic system membrane filtration after standing reaction a period of time Obtain solid product；

Solid product cleaning, filtering, naturally dry are obtained Fe-PANI/Au powder by S4；

S5, by the glass-carbon electrode successively use 3 μm, 1 μm, 0.3 μm, after the alumina powder grinding and polishing of 50nm it is spare；

S6 takes the Fe-PANI/Au powder ultrasonic disperse of 1~3mg in 0.5mL dehydrated alcohol, and the Nafion of 5~15 μ L is added Solution ultrasonic disperse forms it into uniform suspension；

S7, the glassy carbon electrode surface for taking the suspension of 10-40 μ L to be added drop-wise to after step S5 polishing with 10-20 μ L/ times, stands to molten Continue that suspension is added dropwise after liquid volatilization, operation finally obtains Fe-PANI/Au modified electrode repeatedly.

2. preparation method as described in claim 1, which is characterized in that in step s 2, mixed solution is protected from light the time and is 10-50h。

3. preparation method as described in claim 1, which is characterized in that in step s3, after ammonium persulfate-hydrochloric acid solution is added The standing reaction time is 15-35min.

4. preparation method as described in claim 1, which is characterized in that in step s 4, the step of solid product is cleaned packet It includes:

The solid product is successively cleaned filtration product with distilled water, hydrochloric acid solution, ethanol washing by S41, hydrochloric acid solution it is dense Degree range is 0.1-2mol/L.

5. preparation method as described in claim 1, which is characterized in that in step s 6, the Fe-PANI/ for taking 1~3mg In 0.5mL dehydrated alcohol, the Nafion solution ultrasonic disperse that 5~15 μ L are added forms it into uniformly Au powder ultrasonic disperse The step of suspension includes:

S61 takes the Fe-PANI/Au powder ultrasonic disperse of 2mg in 0.5mL dehydrated alcohol, and the Nafion solution that 10 μ L are added is super Sound dispersion forms it into uniform suspension.

6. preparation method as described in claim 1, which is characterized in that in the step s 7, the suspension for taking 10-40 μ L with The 10-20 μ L/ times glassy carbon electrode surface being added drop-wise to after step S5 polishing, standing continue that suspension is added dropwise after solution evaporation, instead Operating the step of finally obtaining Fe-PANI/Au modified electrode again includes:

S71 takes the suspension of 20 μ L to be directly added drop-wise to the glassy carbon electrode surface after step S5 polishing, stands and obtain after solution evaporation To Fe-PANI/Au modified electrode.

7. a kind of Fe-PANI/Au nanocomposite modified electrode, which is characterized in that the nano combined material of Fe-PANI/Au Material modified electrode is to be prepared by the method for any one of claim 1-6；It tests environment are as follows: is modified with Fe-PANI/Au Electrode is that working electrode, graphite electrode or platinum electrode are to carry out DPV test to electrode, the sweet common-battery of saturation extremely reference electrode, In, potential range -0.1V-0.9V (vs.SCE), scan amplitude 50mV, pulse width 50ms, entire environment of testing is in pH= It is carried out in 6.6-7.2 hair phosphate buffer.

Technical field

The present invention relates to a kind of for dopamine, the Fe-PANI/Au nanocomposite modified electrode of uric acid Sensitive Detection And its preparation.

Background technique

Dopamine (DA) is present in cerebral nerve tissue and body fluid, plays in the life system of the mankind important Role is not only the precursor of internal adrenaline biosynthesis or the transmitter of brain information.Dopamine is in human body just Chang Hanliang is 0.2-0.4g/ml.Many benefits such as suitable dopamine can make one to be in a cheerful frame of mind, benefit and Renal vascular diastole, but It is that can cause when the content of dopamine in human body is too low such as schizophrenia, heart failure, parkinsonism, neuromuscular disorders Etc. diseases.Otherwise DA content is excessive, people can be allowed to feel excited, happy, be easy addicted.Therefore, detection nerve is passed in high sensitivity The concentration of matter dopamine has significant application value for physiological function research and clinical disease diagnosis.

At present the common detection method of dopamine have fluorescent spectrometry, colleges and universities' liquid phase method, capillary electrophoresis, colorimetric method, Electrochemical analysis detection method etc..Wherein electrochemical detection method has easy to operate, highly sensitive, good selective, becomes The common method of dopamine detection.So in brain and body fluid, other than dopamine, also contain uric acid (UA) and ascorbic acid (AA), and the oxidizing potential of three is very close, and the presence of uric acid and ascorbic acid produces the measurement of dopamine in detection architecture Raw interference.Therefore while developing highly sensitive dopamine electrochemical detection method, it is necessary to investigate it to uric acid and anti-bad The interference free performance of hematic acid.And polyaniline composite material modified electrode shows its unique advantage in dopamine context of detection.

Polyaniline is that one kind is coexisted by benzene/quinone structure unit, the high-molecular compound linked end to end.The material because have compared with High electrochemical activity and biocompatibility have good application prospect in electrochemical sensing.Composite material is by conducting polymer Electrical property combines with the excellent function of other materials and is expected to be used widely.Studies have shown that by nanometers such as Au, Pt, Ag, Cu Metallic is compound with polyaniline material, and the electric conductivity and electrochemical response performance of polyaniline can be improved, while also retaining The physical and chemical properties of metallic script.There are lone pair electrons on the nitrogen-atoms of aniline monomer, it can be with metal ion Complex compound is formed, therefore the performance of polyaniline material can be optimized to a certain extent by the doping of metal ion.Gather as a result, The composite material of aniline makes polyaniline show preferable application prospect in terms of the analysis detection of dopamine.

Summary of the invention

The present invention provides a kind of Fe-PANI/Au nanocomposites for dopamine, uric acid Sensitive Detection to modify electricity Pole and its preparation can effectively solve the interference and sensitivity problem of dopamine detection process.

The present invention is implemented as follows:

A kind of preparation method of Fe-PANI/Au nanocomposite modified electrode, comprising the following steps:

S1, ultrasound in 50mL dichloromethane solution, which is added, in 0.5mL aniline monomer keeps its evenly dispersed formation transparent uniform Organic phase solution；

S2 is successively slowly added to the gold chloride of the 24.28mM of 0.103ml into the organic phase solution under agitation Solution, 50mL 0.2mol/L N-Methyl pyrrolidone aqueous solution and 0.05mL 0.5mol/L ferric chloride solution, room temperature Under be protected from light stirring a period of time after stand；

0.3g ammonium persulfate is added in the hydrochloric acid solution of the 2mol/L of 8.6mL and forms ammonium persulfate-hydrochloric acid solution by S3, Ammonium persulfate-hydrochloric acid solution is slowly added in step S2 in reaction solution, uses organic system filter membrane after standing reaction a period of time Solid product is obtained by filtration；

Solid product cleaning, filtering, naturally dry are obtained Fe-PANI/Au powder by S4；

S5, by the glass-carbon electrode successively use 3 μm, 1 μm, 0.3 μm, after the alumina powder grinding and polishing of 50nm it is spare；

S6 takes the Fe-PANI/Au powder ultrasonic disperse of 1~3mg in 0.5mL dehydrated alcohol, is added 5~15 μ L's Nafion solution ultrasonic disperse forms it into uniform suspension；

S7, the glassy carbon electrode surface for taking the suspension of 10-40 μ L to be added drop-wise to after step S5 polishing with 10-20 μ L/ times, stands Continue that suspension is added dropwise after solution evaporation, operation finally obtains Fe-PANI/Au modified electrode repeatedly.

The present invention furthermore provides the Fe-PANI/Au nanocomposite modified electrode obtained by the above method；Its Test environment are as follows: by working electrode, graphite electrode or platinum electrode of Fe-PANI/Au modified electrode be to electrode, the sweet common-battery of saturation Extremely reference electrode carries out DPV test, wherein potential range -0.1V-0.9V (vs.SCE), scan amplitude 50mV, pulse are wide 50ms is spent, entire environment of testing carries out in pH=6.6-7.2 hair phosphate buffer.

The beneficial effects of the present invention are: test of the Fe-PANI/Au modified electrode to DA, can effectively exclude UA's and AA Interference.Wherein, the DPV of DA is detected on Fe-PANI/Au modified electrode, and detection is limited to 0.001 μM；0.1 μM is limited to UA detection, Compared with Fe-PANI and PANI/Au modified electrode, Fe-PANI/Au modified electrode has higher detection sensitivity to UA.It can It is applied to the Sensitive Detection of DA and UA simultaneously.

Detailed description of the invention

It, below will be to use required in embodiment in order to illustrate more clearly of the technical solution of embodiment of the present invention Attached drawing be briefly described, it should be understood that the following drawings illustrates only certain embodiments of the present invention, therefore is not to be seen as It is the restriction to range, it for those of ordinary skill in the art, without creative efforts, can be with root Other relevant attached drawings are obtained according to these attached drawings.

It is 0.1M that Fig. 1, which is in concentration, and AA, 200 μM of the DA of UA, 2mM of 1mM are in Fe- in the phosphate buffer that pH is 6.8 DPV figure on PANI modified electrode.

Fig. 2 is in 0.1M, the phosphate buffer that pH is 6.8, and the AA of UA, 2mM of 1mM, 200 μM of DA are in PANI/Au DPV figure on modified electrode.

It is 0.1M that Fig. 3, which is in concentration, and AA, 200 μM of the DA of UA, 2mM of 1mM are in Fe- in the PBS solution that pH is 6.8 DPV figure on PANI/Au modified electrode.

It is 0.1M that Fig. 4, which is in concentration, and pH is in 6.8 phosphate buffer, a series of concentration DA modifies in Fe-PANI/Au DPV figure on electrode.

Fig. 5 is the linear relationship curve graph of DA concentration and peak current.

It is 0.1M that Fig. 6, which is in concentration, and pH is in 6.8 phosphate buffer, various concentration UA modifies electricity in Fe-PANI/Au DPV figure on extremely.

Fig. 7 is the linear relationship curve graph of UA concentration and peak current.

Specific embodiment

To keep the purposes, technical schemes and advantages of embodiment of the present invention clearer, implement below in conjunction with the present invention The technical solution in embodiment of the present invention is clearly and completely described in attached drawing in mode, it is clear that described reality The mode of applying is some embodiments of the invention, rather than whole embodiments.Based on the embodiment in the present invention, ability Domain those of ordinary skill every other embodiment obtained without creative efforts, belongs to the present invention The range of protection.Therefore, the detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit below and is wanted The scope of the present invention of protection is sought, but is merely representative of selected embodiment of the invention.Based on the embodiment in the present invention, Every other embodiment obtained by those of ordinary skill in the art without making creative efforts belongs to this Invent the range of protection.

The embodiment of the present invention provides a kind of preparation method of Fe-PANI/Au nanocomposite modified electrode, including following Step:

S1, ultrasound in 50mL dichloromethane solution, which is added, in 0.5mL aniline monomer keeps its evenly dispersed formation transparent uniform Organic phase solution；

S2 is successively slowly added to the gold chloride of the 24.28mM of 0.103ml into the organic phase solution under agitation Solution, 50mL 0.2mol/L N-Methyl pyrrolidone aqueous solution and 0.05mL 0.5mol/L ferric chloride solution, room temperature Under be protected from light stirring a period of time after stand；

0.3g ammonium persulfate is added in the hydrochloric acid solution of the 2mol/L of 8.6mL and forms ammonium persulfate-hydrochloric acid solution by S3, Ammonium persulfate-hydrochloric acid solution is slowly added in step S2 in reaction solution, uses organic system filter membrane after standing reaction a period of time Solid product is obtained by filtration；

Solid product cleaning, filtering, naturally dry are obtained Fe-PANI/Au powder by S4；

S5, by the glass-carbon electrode successively use 3 μm, 1 μm, 0.3 μm, after the alumina powder grinding and polishing of 50nm it is spare；

S6 takes the Fe-PANI/Au powder ultrasonic disperse of 1~3mg in 0.5mL dehydrated alcohol, is added 5~15 μ L's Nafion solution ultrasonic disperse forms it into uniform suspension；

S7, the glassy carbon electrode surface for taking the suspension of 10-40 μ L to be added drop-wise to after step S5 polishing with 10-20 μ L/ times, stands Continue that suspension is added dropwise after solution evaporation, operation finally obtains Fe-PANI/Au modified electrode repeatedly.

The test environment of the Fe-PANI/Au modified electrode are as follows: using Fe-PANI/Au modified electrode as working electrode, stone Electrode ink or platinum electrode are to carry out DPV test to electrode, the sweet common-battery of saturation extremely reference electrode, wherein potential range -0.1V- 0.9V (vs.SCE), scan amplitude 50mV, pulse width 50ms, entire environment of testing is in pH=6.6-7.2 hair phosphoric acid buffer It is carried out in liquid.As further improved, in addition, the pH value of environment also has larger impact to test in entire test, when When pH=6.6-7.2 is more than this range, the proton doping level of polyaniline changes, to influence to detect the anti-dry of substance Immunity, sensitivity and stability, it is therefore preferred that entirely test environment carries out in the phosphate buffer of pH=6.8-7.2.

As further improved, in step s 2, it is 10-50h that mixed solution, which is protected from light the time,.

As further improved, in step s3, being added after ammonium persulfate-hydrochloric acid solution and standing the reaction time is 15- 35min。

As further improved, in step s 4, the step of solid product is cleaned, includes:

The solid product is successively cleaned filtration product, hydrochloric acid solution with distilled water, hydrochloric acid solution, ethanol washing by S41 Concentration range be 0.1-2mol/L.In step in S41, hydrochloric acid solution clean so that polyaniline keep certain electric conductivity and Dispersibility.The hydrochloric acid cleaning solution of right excessively high solubility will influence the cleaning of product simultaneously so that polyaniline is easily dispersed into homogeneous solution Destroy filtering film layer.Therefore it is furthermore preferred that the concentration range of the hydrochloric acid solution is 0.1-1.2mol/L.

As further improved, in step s 6, the Fe-PANI/Au powder ultrasonic disperse for taking 1~3mg in In 0.5mL dehydrated alcohol, Nafion solution ultrasonic disperse the step of forming it into uniform suspension packet of 5~15 μ L is added It includes:

S61 takes the Fe-PANI/Au powder ultrasonic disperse of 2mg in 0.5mL dehydrated alcohol, and the Nafion that 10 μ L are added is molten Liquid ultrasonic disperse forms it into uniform suspension.

As further improved, in the step s 7, the suspension for taking 10-40 μ L is added drop-wise to step with 10-20 μ L/ times Glassy carbon electrode surface after rapid S5 polishing, standing continue that suspension is added dropwise after solution evaporation, and operation finally obtains Fe- repeatedly The step of PANI/Au modified electrode includes:

S71 takes the suspension of 20 μ L to be directly added drop-wise to the glassy carbon electrode surface after step S5 polishing, stands to solution evaporation After obtain Fe-PANI/Au modified electrode.