An automatic detection method for caffeine in electronic cigarette liquid

Abstract

An automatic detection method of caffeine in an e-cigarette solution is characterized in that automatic operation of electronic cigarette sample pretreatment and online gas chromatography-mass spectrometry detection are combined, that is, an e-cigarette solution sample is directly placed in a chromatographic bottle of a chromatograph, later, the adding amounts of water, dichloromethane and internal standard matter are set, an instrument is set to perform automatic adding operation, vortex operation is performed, and a lower-layer dichloromethane phase is taken and detected online in a gas chromatography-mass spectrometer. Compared with existing detection method, the automatic detection method has the technical advantages as follows: 1, the difference and the accuracy error during manual sample treatment are reduced through whole-course automatic operation of sample pretreatment and sample injection, the repeatability is high and the general survey and analysis results are reliable; fewsolvents and samples are consumed, and the method is more environmentally friendly; the method is rapid, efficient and applicable of general survey and analysis of samples on a large scale, and 15 samples can be treated and analyzed once; 2, the condition of inaccurate detection results of a target object due to solvent volatilization before conventional offline detection is avoided, each sampleis immediately injected after pretreatment, and the detection result is accurate and reliable.

Description

technical field [0001] The invention belongs to the technical field of measuring electronic cigarette liquid, and in particular relates to an automatic detection method for caffeine in electronic cigarette liquid. In this method, the e-cigarette liquid pretreatment is automated and combined with online gas chromatography-mass spectrometry detection, the pretreatment uses less solvent, the whole process is automated, and the accuracy and repeatability are good. Background technique [0002] Electronic cigarette (electrical cigarette, e-cigarette), also known as electronic nicotine delivery systems (ENDS), is an electronic device that delivers nicotine to the respiratory system by means of electronic heating. new way. E-cigarette liquid is mainly composed of nicotine, propylene glycol, glycerin or polyethylene glycol, and a small amount of flavor is added to prepare different flavors to meet the needs and hobbies of consumers. [0003] Caffeine is a xanthine alkaloid compoun...

AI Technical Summary

Problems solved by technology

[0004] At present, the analysis methods of caffeine in the literature focus on the detection of instrument analysis, and there are few studies on pretreatment. Most of the pretreatment of caffeine is manual offline treatment, that is, adding solvent to the sample for extraction, and taking the extract into the instrument for analysis. However, manual pretreatment is not suitable for the general survey analysis of large batches of samples. The deviation introduced by human factors in the pretreatment is large, the system error is large, and the precision is poor; when a large number of samples are analyzed, there will be a long waiting time before sample injection, and the solvent Volatility will lead to changes in the concentration of the target substance and inaccurate measurement results

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