Jingcun Wu

This article describes a liquid chromatography–tandem mass spectrometry (LC–MS/MS) method for the analysis of coumarin in various tobacco matrices and electronic cigarette (E-cig) liquids, and highlights the importance of evaluating different MS/MS transitions of an analyte in complex sample matrices to overcome matrix effects. Matrix interfering components were separated from analyte using a C18 ultrahigh-pressure liquid chromatography (UHPLC) column with a larger inner diameter (3.0 mm, or 4.6 mm). Matrix suppressions on analyte responses were corrected by isotope dilution. Four different MS/MS transitions of coumarin were studied in each sample matrix to select a suitable MS/MS transition for analyte quantification based on matrix effects on each MS/MS transition. The method was validated using different tobacco matrices and E-cig liquids.

This method has greater sensitivity and a shorter LC analysis time than the AOAC method. It also requires less instrument maintenance, enhances column lifetime by requiring a smaller sample volume, and reduces cost by replacing acetonitrile with methanol in the mobile phase.

Mycotoxins are toxic metabolites produced by fungal species often found in agricultural products. An accurate method for analyzing 12 regulated mycotoxins is described using UHPLC–MS/MS. The method demonstrated limits of quantitation (LOQs) for all analytes below stringent regulatory limits, making the method suitable for routine mycotoxin analysis.

Tobacco-specific nitrosamines are important carcinogens in tobacco products. This article describes a fast, sensitive, selective, and robust method for analysis of these compounds in various tobacco samples by liquid chromatography–tandem mass spectrometry (LC–MS/MS). The separation of analytes from matrix interfering components was performed using a C18 column with simple LC–MS mobile phases. To minimize sample matrix effects on each analyte, a separate internal standard was used for each analyte. Two MS/MS ion pairs were used for each analyte for analyte confirmation and quantification, further enhancing the method’s selectivity and accuracy. The method was validated using different tobacco matrices.