Method for Determination of Non-volatile Organic Acids and Fatty Acids in Tobacco by Micro Extraction Separation-Gas Chromatography

Abstract

The invention relates to a method for determining non-volatile organic acids and fatty acids in tobacco by micro-extraction separation-gas chromatography, and belongs to the technical field of analytical chemistry. The method comprises the steps of: pulverizing the tobacco sample to be tested and placing it in a microwave reaction tank, adding an internal standard solution and a methanol solution of sulfuric acid therein, performing microwave reaction, and filtering to obtain a filtrate; the internal standard is adipic acid; Take the filtrate and mix it with saturated sodium chloride solution and transfer it to a micro-extraction device, use dichloromethane as the extraction agent to carry out vibration extraction, after standing for stratification, take the lower clear liquid; the obtained lower clear liquid is analyzed by gas chromatography , quantified by external standard method. Compared with the conventional method, the extraction and derivatization reaction speed of the inventive method is greatly accelerated, and can be completed in only 10 minutes; the consumption of derivatization reagents and extraction organic solvents is greatly reduced, and the operation is simple, high in accuracy and good in repeatability, and is suitable for It is suitable for the analysis of large batches of samples and is easy to popularize and apply.

Description

technical field [0001] The invention belongs to the technical field of analytical chemistry, and in particular relates to a micro-extraction separation-gas chromatography method for measuring non-volatile organic acids and fatty acids in tobacco. Background technique [0002] There are a variety of organic acids in tobacco. It is generally believed that organic acids in tobacco leaves can be divided into volatile and non-volatile (except amino acids) and some higher fatty acids. Most of the relatively high content are dibasic acids in non-volatile organic acids. and tribasic acids, the content of malic acid, citric acid, oxalic acid and malonic acid is relatively high (accounting for about 5% to 18% in flue-cured tobacco), and the non-volatile organic acids and fatty acids in tobacco have an important impact on the quality of tobacco . Therefore, the determination of non-volatile organic acids, higher fatty acids and their derivatives in tobacco has gradually become the con...

AI Technical Summary

Problems solved by technology

The method of methyl esterification with sulfuric acid-methanol is the most commonly used method. This method is to dissolve the organic acid in the sample by using sulfuric acid-methanol solution. The operation needs to add the tobacco sample into the sulfuric acid-methanol solution and reflux for several hours. The operation is very time-consuming and consumes a lot of organic solvents.

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