阅读说明：本技术 Pt@Au/C双金属纳米材料及其检测葡萄糖的方法 (Pt @ Au/C bimetallic nano material and method for detecting glucose by using same ) 是由 林玲玲 游东宏 叶陈清 陈�峰 徐雪琴 于 2019-08-26 设计创作，主要内容包括：本发明提供了一种碳负载铂金(Pt@Au/C)双金属纳米材料,所述Pt@Au/C双金属纳米材料用于葡萄糖的催化检测,其中,所述Pt@Au/C双金属纳米材料中Pt和Au的质量比为1:1,Pt和Au含量在所述Pt@Au/C双金属纳米材料中质量占比分别可低至0.4％。本发明还提供一种采用上述Pt@Au/C双金属纳米材料检测葡萄糖的方法,该方法检测灵敏度高、抗干扰能力强。(The invention provides a carbon-loaded platinum (Pt @ Au/C) bimetallic nano material which is used for catalytic detection of glucose, wherein the mass ratio of Pt to Au in the Pt @ Au/C bimetallic nano material is 1:1, and the mass ratio of Pt and Au contents in the Pt @ Au/C bimetallic nano material can be respectively reduced to 0.4%. The invention also provides a method for detecting glucose by adopting the Pt @ Au/C bimetal nano material, which has high detection sensitivity and strong anti-interference capability.)

1. The Pt @ Au/C bimetal nano material is used for catalytic detection of glucose and is characterized in that the mass ratio of Pt to Au in the Pt @ Au/C bimetal nano material is 1:1, and the mass ratio of the Pt to Au contents in the Pt @ Au/C bimetal nano material is respectively as low as 0.4-4%.

2. The Pt @ Au/C bimetallic nanomaterial of claim 1, wherein the Pt and Au contents are 0.4% by mass of the Pt @ Au/C bimetallic nanomaterial, respectively.

3. The Pt @ Au/C bimetallic nanomaterial of claim 1, wherein the Pt @ Au/C bimetallic nanomaterial comprises a carbon-supported particle and a Pt @ Au bimetallic particle, the Pt @ Au bimetallic particle being uniformly dispersed on the carbon-supported particle.

4. The Pt @ Au/C bimetallic nanomaterial of claim 3, wherein the carbon-supported particle has a diameter in the range of 20 nm to 50nm, and the Pt @ Au bimetallic particle has a diameter of less than 10 nm.

5. A method for detecting glucose by adopting a Pt @ Au/C bimetal nano material comprises the following steps:

Preparing a Pt @ Au/C bimetal nano material modified electrode by adopting a Pt @ Au/C bimetal nano material, wherein the Pt @ Au/C bimetal nano material is the Pt @ Au/C bimetal nano material in any one of claims 1 to 4;

And detecting the electrochemical response of the glucose on the Pt @ Au/C bimetal nano material modified electrode by using a cyclic voltammetry method by using a saturated calomel electrode as a reference electrode, a graphite electrode as an auxiliary electrode and the Pt @ Au/C bimetal nano material modified electrode as a working electrode, wherein NaOH is used as an alkaline medium in a glucose solution to be detected, and the detection potential range is-0.6V-0.6V.

6. The method for detecting glucose by using the Pt @ Au/C bimetal nanomaterial as claimed in claim 5, wherein the preparation step of the Pt @ Au/C bimetal nanomaterial modified electrode comprises the following steps: putting the Pt @ Au/C bimetal nano material into a centrifugal tube, adding absolute ethyl alcohol and a Nafion solution, and performing ultrasonic dispersion; and (3) dripping the solution subjected to ultrasonic dispersion on the surface of the glassy carbon electrode by adopting a dripping method, and standing for later use after the solvent is volatilized at room temperature.

7. The method for detecting glucose by using the Pt @ Au/C bimetal nanomaterial as claimed in claim 6, wherein the proportioning conditions of the Pt @ Au/C bimetal nanomaterial, absolute ethyl alcohol and Nafion solution comprise: when the Pt @ Au/C bimetallic nano material is 2mg, the absolute ethyl alcohol is 0.5ml, the Nafion solution is 10 mu l, and the ultrasonic dispersion time is 10-60 min.

8. the method for detecting glucose by using the Pt @ Au/C bimetal nanomaterial as claimed in claim 5, wherein the detection limit of the electrochemical response of the detected glucose on the Pt @ Au/C bimetal nanomaterial modified electrode is 100 μ M, and the scanning speed is 0.05Vs^-1。

Technical Field

The invention relates to a Pt @ Au/C bimetal nano material, in particular to a Pt @ Au/C bimetal nano material for detecting glucose.

Background

Glucose is an important compound in organisms and has an important influence on the physical health of human beings. Abnormal glucose concentration in the human body can cause various diseases, such as diabetes, hypertension, neurohypoglycemia, and the like. In recent years, the proportion of diabetes patients in China is gradually increased and reaches 11.4 hundred million at present. Therefore, it is very important to detect the glucose content of human body, including blood sugar and urine glucose content.

Currently, methods for detecting glucose include gas chromatography, spectrophotometry, optical rotation, electrochemical detection, and the like. The electrochemical method is a means for rapidly detecting glucose, and gradually becomes a hot spot for detecting glucose. Among them, glucose electrochemical enzyme sensors and glucose electrochemical non-enzyme sensors are classified according to whether or not an enzyme catalyst is contained. The construction mechanism of the glucose electrochemical enzyme sensor is based on the specific recognition function of enzyme to reaction substrates, and the application of the glucose electrochemical enzyme sensor is limited due to the problems of poor stability, poor environmental adaptability, high price and the like. The working mechanism of the glucose electrochemical non-enzymatic sensor is based on that glucose is catalytically oxidized on a modified electrode with catalytic activity to be converted into an electrochemical signal, and the glucose electrochemical non-enzymatic sensor has the advantages of good stability, low price and wide application range, and gradually becomes a main research direction. However, the current glucose electrochemical non-enzymatic sensor still needs to be improved in terms of detection limit and anti-interference capability, and the research on active materials with glucose catalytic oxidation is a current research hotspot.

Disclosure of Invention

the invention provides a Pt @ Au/C bimetallic nano material and a method for detecting glucose, and the Pt @ Au/C bimetallic nano material has better glucose detection sensitivity and anti-interference performance.

The invention is realized by the following steps:

The Pt @ Au/C bimetal nano material is used for catalytic detection of glucose, wherein the mass ratio of Pt to Au in the Pt @ Au/C bimetal nano material is 1:1, and the mass ratio of Pt and Au contents in the Pt @ Au/C bimetal nano material is respectively as low as 0.4-4%.

As a further improvement, the Pt and Au contents in the Pt @ Au/C bimetal nanomaterial respectively account for 0.4% by mass.

A method for detecting glucose by adopting a Pt @ Au/C bimetal nano material comprises the following steps: preparing a Pt @ Au/C bimetal nano material modified electrode by adopting a Pt @ Au/C bimetal nano material, wherein the Pt @ Au/C bimetal nano material is the Pt @ Au/C bimetal nano material; and detecting the electrochemical response of the glucose on the Pt @ Au/C bimetal nano material modified electrode by using a cyclic voltammetry method by using a saturated calomel electrode as a reference electrode, a graphite electrode as an auxiliary electrode and the Pt @ Au/C bimetal nano material modified electrode as a working electrode, wherein NaOH is used as an alkaline medium in a glucose solution to be detected, and the detection potential range is-0.6V-0.6V.

the invention has the beneficial effects that: when the Pt @ Au/C bimetallic nano material with the Pt/Au ratio of 1:1 and the Pt and Au contents of 0.4% respectively is used as the catalyst for detecting glucose, the signal-to-noise ratio is better, the detection limit is 100 mu M, and the detection process is not interfered by electrochemical response signals of Dopamine (DA), Ascorbic Acid (AA) and Uric Acid (UA). The mass ratio of the Pt and Au contents in the Pt @ Au/C bimetallic nano material can be respectively reduced to 0.4%, so that the sensor has price advantage compared with an electrochemical enzyme sensor and other noble metal electrochemical sensors.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIG. 1 is a flow chart of a method for detecting glucose by using Pt @ Au/C bimetallic nano-materials provided by the invention.

FIG. 2 is a cyclic voltammogram of a Pt @ Au/C bimetal nano material modified electrode provided by the invention under different concentrations of glucose.

FIG. 3 is a linear relationship diagram of the peak current and the glucose concentration of the Pt @ Au/C bimetal nano material modified electrode cyclic voltammetry detection provided by the invention.

FIG. 4 is a cyclic voltammogram of Pt @ Au/C bimetal nanomaterial modified electrodes with different platinum ratios provided by the invention in a glucose solution under the condition of NaOH medium.

FIG. 5 is a cyclic voltammogram of glucose, DA, AA, and UA solutions of the Pt @ Au/C bimetal nanomaterial-modified electrode provided by the invention under NaOH medium conditions, respectively.

FIG. 6 is a cyclic voltammogram of glucose solution of Pt @ Au/C bimetal nanomaterial modified electrodes with different platinum contents provided by the invention under the condition of NaOH medium.

Detailed Description

in order to make the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings of the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention. Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

The invention provides a Pt @ Au/C bimetal nano material which is used for catalytic detection of glucose. The mass ratio of Pt to Au in the Pt @ Au/C bimetal nano material is 1:1, and the content of Pt and Au is respectively as low as 0.4-4%. Specifically, the mass ratio of the Pt and Au contents in the Pt @ Au/C bimetal nanomaterial can be respectively as low as 0.4%. The carbon load particles and the Pt @ Au bimetallic particles in the Pt @ Au/C bimetallic nano material are uniformly dispersed. The carbon-supported particles have a diameter in the range of 20-50 nm. The Pt @ Au bimetallic particles are less than 10nm in diameter.

The Pt @ Au/C bimetallic nano material is prepared by taking carbon powder as a carrier through a hydrothermal synthesis method. The preparation method of the Pt @ Au/C bimetal nano material comprises the following steps:

Providing carbon powder, trisodium citrate and ethylene glycol, and placing the mixture into a beaker for ultrasonic dispersion.

In the embodiment, the mass of the carbon powder is 20mg, the mass of the trisodium citrate is 66mg, the trisodium citrate is dissolved by 1ml of distilled water before use, the volume of the ethylene glycol is 20ml, and the ultrasonic dispersion is ultrasonic dispersion in an ultrasonic cleaner for 15 min.

and step two, adding a potassium chloroplatinate solution and a chloroauric acid solution, adjusting the pH of the reaction solution to 10 by using a 2% NaOH solution, and transferring the reaction solution to a hydrothermal reaction kettle.

In this embodiment, the content and the ratio of the potassium chloroplatinate solution and the chloroauric acid solution can be calculated according to the mass content and the ratio of Pt and Au in the Pt @ Au bimetal to be prepared.

and step three, sealing and placing the mixture in an oven, heating the mixture to 120 ℃, reacting the mixture for 3.5 hours, filtering the product after cooling by using a filter membrane with the aperture of 0.22 mu m, washing the product by using ethanol, and drying the product at a low temperature.

Referring to fig. 1, the present invention provides a method for detecting glucose by using Pt @ Au/C bimetal nano material, which comprises the following steps:

S1, preparing a Pt @ Au/C bimetal nano material modified electrode by adopting the Pt @ Au/C bimetal nano material provided by the embodiment;

And S2, taking a saturated calomel electrode as a reference electrode, a graphite electrode as an auxiliary electrode, a Pt @ Au/C bimetal nano material modified electrode as a working electrode, and detecting the electrochemical response of the glucose on the Pt @ Au/C bimetal nano material modified electrode by using a cyclic voltammetry method, wherein NaOH is taken as an alkaline medium in the glucose solution to be detected, and the detection potential range is-0.6V-0.6V.

In step S1, the preparation method of the Pt @ Au/C bimetal nanomaterial modified electrode includes: putting the Pt @ Au/C bimetal nano material into a centrifugal tube, adding absolute ethyl alcohol and a Nafion solution, and performing ultrasonic dispersion; and (3) dripping the solution subjected to ultrasonic dispersion on the surface of the glassy carbon electrode by adopting a dripping method, and standing for later use after the solvent is volatilized at room temperature.

In the embodiment, the Pt @ Au/C bimetallic nano material has the mass of 2mg, the absolute ethyl alcohol of 0.5ml, the Nafion solution of 10 mu l and the ultrasonic dispersion time of 10-60 min.

In step S2, the electrochemical response of glucose on the Pt @ Au/C bimetal nano material modified electrode under the condition of NaOH medium is tested by adopting a three-electrode system and a potential detection range of-0.6V-0.6V (vs. SCE), the detection limit can reach 100 mu M, and the scanning speed is 0.05Vs^-1. FIG. 2 shows cyclic voltammograms of different concentrations of glucose on Pt @ Au/C bimetallic nanomaterial-modified electrodes in 0.08M NaOH medium. The glucose concentrations shown in the graphs from bottom to top in the figure were 0.01mM, 0.02mM, 0.04mM, 0.07mM, 0.1mM, 0.2mM, 0.4mM, 1mM, 4mM, and 10mM, and it can be seen that the peak current of glucose oxidation increased with increasing glucose concentration. FIG. 3 is a graph showing the relationship between the oxidation current and the concentration of glucose at an oxidation potential of-0.3V in the cyclic voltammetry, with a detection limit of 100. mu.M, a linear relationship of I (mA) -0.01757 +0.01497C (mM), and a correlation coefficient of R²0.99221, presents a good linear relationship and can be used for the quantitative detection of glucose.

In order to illustrate the detection performance of the Pt @ Au/C bimetallic nanomaterial modified electrode on glucose, the influence of Pt @ Au bimetallic materials with different platinum contents and proportions on glucose detection and the electrochemical response of interfering substances are specifically described.

1. Effect of platinum ratio on electrochemical response signals of glucose

FIG. 4 shows the cyclic voltammograms of 10mM glucose solution on Pt @ Au/C bimetal nanomaterial modified electrodes with different platinum ratios under 0.08M NaOH medium, where the platinum ratios are 1:1, 1:2, 2:1, and 4:1, respectively, and it can be seen that two glucose oxidation peaks appear at-0.5V-0V and 0V-0.4V. With the increase of the proportion of Au in the Pt @ Au bimetal, the stronger the redox signal (redox signal I) caused by glucose adsorbed on the surface of the Pt @ Au/C bimetal nano material modified electrode, the stronger the redox signal (redox signal II) caused by glucose diffused to the surface of the electrode in the solution phase, wherein the redox signal II of glucose on the Pt @ Au/C bimetal nano material modified electrode is strongest when the proportion of platinum to gold is 1: 1.

Electrochemical response of DA, AA and UA on Pt @ Au/C bimetal nano material modified electrode

In the detection of glucose liquid, substances such as DA, AA, UA and the like exist, and certain interference exists in the detection of glucose. FIG. 5 shows the cyclic voltammograms of Pt @ Au/C bimetal nanomaterial-modified electrode in 10mM glucose, 5mM DA, 5mM AA, and 5mM UA solutions respectively under 0.08M NaOH medium. As can be seen from the figure, DA and AA begin to show redox signals at-0.24V, and UA begins to show redox signals at-0.06V, i.e., in the potential range of-0.24V-0.6V, interference exists between DA, AA, UA and glucose detection. In the potential range of-0.5V to-0.24V, the electrochemical response signal of the glucose is not interfered by DA, AA and UA electrochemical response signals, and the potential range can be used as the preferred potential range for detecting the glucose.

3. Effect of platinum content on glucose electrochemical response signals

FIG. 6 shows the cyclic voltammograms of a 10mM glucose solution on Pt @ Au/C bimetallic nanomaterial modified electrodes with different platinum contents under the condition of 0.08M NaOH medium, where the platinum contents are 0.1%, 0.4%, 0.7%, 1%, 2%, and 4%, respectively. It can be seen from the figure that two glucose oxidation peaks appear at-0.5V-0V and 0V-0.4V; with the increase of platinum content (0.1% → 0.4%), the redox signal II of glucose increases, which can be attributed to the increase of the platinum load per unit area of the Pt @ Au/C bimetallic nanomaterial, and the active sites where electrochemical reaction can occur increase, so that the redox signal II of glucose increases; when the platinum content is 0.4% → 1%, the glucose redox signal II is not very different because the glucose electrochemical response behavior under the condition is influenced by the glucose diffusion rate in the solution phase and becomes a determination step of the glucose electrochemical reaction rate, so that glucose does not show a significant signal difference on the modified electrodes with different platinum contents under the condition; influenced by the adsorption effect of glucose on the surface of the Pt @ Au/C bimetal nano material modified electrode, the glucose adsorbable sites on the surface of platinum in unit volume are increased along with the increase of the platinum content, and the glucose oxidation reduction signal I is increased. Although the oxidation peak of glucose appearing at 0V-0.4V has signal enhancement along with the increase of platinum content, under the potential condition, the electrochemical response signal of glucose is easily interfered by the electrochemical response signals of DA, AA, UA and other substances; the electrochemical response signal of a glucose oxidation peak appearing at-0.5V-0V on the Pt @ Au/C bimetal nano material modified electrode with the platinum content of 0.4% or more than 0.4% respectively shows excellent sensitivity. In view of saving expenses, the embodiment preferably uses Pt @ Au/C bimetal nano materials with 0.4% of platinum content to detect glucose.

The Pt @ Au/C bimetallic nano material and the method for detecting glucose by adopting the Pt @ Au/C bimetallic nano material have the following advantages: when the Pt @ Au/C bimetallic nano-material with the platinum ratio of 1:1 and the platinum content of 0.4% respectively is adopted to detect glucose, the signal-to-noise ratio is good, the detection limit is 100 mu M, and the sensitivity is high; detecting glucose by adopting electrochemical response current in a potential range of-0.5V to-0.24V, wherein the detection process is not interfered by electrochemical response signals of Dopamine (DA), Ascorbic Acid (AA) and Uric Acid (UA); the mass ratio of the platinum content in the Pt @ Au/C bimetallic nano material can be respectively reduced to 0.4%, so that the sensor has price advantage compared with an electrochemical enzyme sensor and other noble metal electrochemical sensors.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.