Rapid in-situ analysis of tobacco chemical composition via ultrasonic nebulization extraction coupled with atmospheric pressure photoionization mass spectrometry

Abstract

A rapid in-situ analytical method combining ultrasonic nebulization extraction with atmospheric pressure photoionization mass spectrometry was developed for direct detection of endogenous compounds in complex tobacco matrices. The ultrasonic nebulization enabled efficient extraction and aerosolization of samples, while dopant-assisted photoionization significantly enhanced ionization efficiency (e.g., nicotine signal increased by ~100-fold). A total of 35 endogenous constituents, including alkaloids, organic acids, phenols, and amino acids, were characterized. Under optimized conditions, the relative standard deviations of nicotine and salicylic acid signals were 4.8% and 5.6% (n = 11) in positive and negative ion modes, respectively, indicating good precision. The standard addition method effectively minimized matrix effects and allowed accurate quantification of eight representative compounds such as nicotine, quinic acid, and proline, all showing excellent linearity (R2 > 0.99) with contents ranging from 0.03 to 20.4 μg/mg. The method requires no tedious pretreatment or chromatographic separation, offering in-situ, rapid, and sensitive analysis with minimal sample consumption, and providing an efficient new strategy for qualitative and quantitative profiling of chemical constituents in tobacco and other economic crops.