Electrochemical method for determining nicotine content in tobacco and tobacco related product

Abstract

The invention provides an electrochemical method for determining nicotine content in tobacco and tobacco-related products. The method comprises the following steps: 1) performing acidolysis on tobaccoand tobacco-related products, filtering, and adding an electrolyte into the filtrate to obtain a sample solution; 2) adding the nicotine standard sample into an electrolyte to dilute and fix the volume to obtain a standard solution; 3) dropwise adding acid into the selected electrode, and performing electrochemical treatment by adopting cyclic voltammetry to obtain a pretreated working electrode;and 4) dropwise adding the sample solution and the standard solution to a working electrode for square wave voltammetry determination, and calculating the content of nicotine in the sample solution through a standard curve method. The electrochemical method for determining nicotine content in tobacco and tobacco related products provided by the invention is simple in preparation process, stable in electrode performance, good in reproducibility, low in detection cost, high in detection speed and high in detection accuracy.

Description

technical field

[0001] The invention belongs to the technical field of electrochemical analysis and detection, relates to an electrochemical method for measuring the nicotine content in tobacco and tobacco-related products, and in particular relates to a direct, simple, fast and accurate determination of tobacco and tobacco-related products (tobacco leaves, cut stems) , sheet, finished cigarettes, electronic cigarettes, snus and heat-not-burn cigarettes, etc.) electrochemical method for nicotine content. Background technique

[0002] Tobacco is a special economic crop with a long history, which is widely planted in countries such as the United States, China, India, Brazil and Cuba. The total output, total area and cigarette production of tobacco planting in my country rank first in the world at present, and it has become an important source of consumption and taxation in my country. Smoking is harmful to health is a major issue of common concern around the world, reducing t...

Examples

Embodiment 1

[0057] Take 40 mg of tobacco leaves and pulverize into powder, and dissolve with 5 mL of 1.0 v / v% acetic acid aqueous solution for 1 min. Then, filter with a 0.45 μm filter membrane, take 2 mL of the filtrate into a centrifuge tube, add 0.01 mol / L PBS buffer solution and mix well to obtain sample solution 1#. Wherein, the volume ratio of filtrate and electrolyte is 1:1.

[0058] Take a nicotine standard stock solution with a concentration of 1000 μg / g as a nicotine standard sample, add 0.01 mol / L PBS buffer solution to dilute to volume, and obtain a series of standard solutions with different concentrations. Wherein, the concentration of nicotine in the standard solution is 10 μg / g, 20 μg / g, 40 μg / g, 60 μg / g, 80 μg / g, 100 μg / g, 120 μg / g, 150 μg / g, 180 μg / g, 200 μg / g respectively.

[0059] The above-mentioned PBS buffer solution is weighed 0.135g KH 2 PO 4 , 0.71g Na 2 HPO 4 12H 2 O, 4g NaCl, 0.1g KCl, add 400mL deionized water and stir to dissolve, add concentrated hydro...

Embodiment 2

[0064] Prepare a series of standard solutions with different concentrations as in Example 1, and measure by the square wave voltammetry in the above-mentioned Example 1, calculate and obtain the regression equation, correlation coefficient and linear range of the standard working curve, and the specific data are shown in Table 1. It can be seen from Table 1 that the regression equation of the standard working curve takes the concentration of each standard solution as the abscissa x, and the corresponding characteristic response current value as the ordinate y, all showing a good linear relationship within a certain linear range, and the standard regression equation Correlation coefficient R 2 Not less than 0.998.

[0065] Table 1

[0066] compound standard curve line R 2

[0067] ln is the log function with base e

Embodiment 3

[0071] Comparing the nicotine content in the tobacco leaf samples of Example 1 and Comparative Example 1, it can be found that the two contents are relatively close, indicating that the accuracy of the determination method in the present invention is good. At the same time, compared with Comparative Example 1, the detection time of Example 1 is shorter, only 30s; there is no need to use expensive GC-MS, and the detection cost is low.

technical field

[0001] The invention belongs to the technical field of electrochemical analysis and detection, relates to an electrochemical method for measuring the nicotine content in tobacco and tobacco-related products, and in particular relates to a direct, simple, fast and accurate determination of tobacco and tobacco-related products (tobacco leaves, cut stems) , sheet, finished cigarettes, electronic cigarettes, snus and heat-not-burn cigarettes, etc.) electrochemical method for nicotine content. Background technique

[0002] Tobacco is a special economic crop with a long history, which is widely planted in countries such as the United States, China, India, Brazil and Cuba. The total output, total area and cigarette production of tobacco planting in my country rank first in the world at present, and it has become an important source of consumption and taxation in my country. Smoking is harmful to health is a major issue of common concern around the world, reducing t...

Examples

Embodiment 1

[0057] Take 40 mg of tobacco leaves and pulverize into powder, and dissolve with 5 mL of 1.0 v / v% acetic acid aqueous solution for 1 min. Then, filter with a 0.45 μm filter membrane, take 2 mL of the filtrate into a centrifuge tube, add 0.01 mol / L PBS buffer solution and mix well to obtain sample solution 1#. Wherein, the volume ratio of filtrate and electrolyte is 1:1.

[0058] Take a nicotine standard stock solution with a concentration of 1000 μg / g as a nicotine standard sample, add 0.01 mol / L PBS buffer solution to dilute to volume, and obtain a series of standard solutions with different concentrations. Wherein, the concentration of nicotine in the standard solution is 10 μg / g, 20 μg / g, 40 μg / g, 60 μg / g, 80 μg / g, 100 μg / g, 120 μg / g, 150 μg / g, 180 μg / g, 200 μg / g respectively.

[0059] The above-mentioned PBS buffer solution is weighed 0.135g KH 2 PO 4 , 0.71g Na 2 HPO 4 12H 2 O, 4g NaCl, 0.1g KCl, add 400mL deionized water and stir to dissolve, add concentrated hydro...

Embodiment 2

[0064] Prepare a series of standard solutions with different concentrations as in Example 1, and measure by the square wave voltammetry in the above-mentioned Example 1, calculate and obtain the regression equation, correlation coefficient and linear range of the standard working curve, and the specific data are shown in Table 1. It can be seen from Table 1 that the regression equation of the standard working curve takes the concentration of each standard solution as the abscissa x, and the corresponding characteristic response current value as the ordinate y, all showing a good linear relationship within a certain linear range, and the standard regression equation Correlation coefficient R 2 Not less than 0.998.

[0065] Table 1

[0066] compound standard curve line R 2

[0067] ln is the log function with base e

Embodiment 3

[0071] Comparing the nicotine content in the tobacco leaf samples of Example 1 and Comparative Example 1, it can be found that the two contents are relatively close, indicating that the accuracy of the determination method in the present invention is good. At the same time, compared with Comparative Example 1, the detection time of Example 1 is shorter, only 30s; there is no need to use expensive GC-MS, and the detection cost is low.

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