Determination of nicotine in tea (Camellia sinensis) by LC–ESI–MS/MS using a modified QuEChERS method

In this work, a method for qualification and quantification of nicotine in dry tea and tea infusions with LC–ESI–MS/MS has been developed. Sample preparation is based on QuEChERS. Nicotine-d4 served as internal standard. This simple and fast method leads to recoveries of 95–104 % and good repeatability. Coefficients of variation are 3.7 % for intra-day precision and 4.6 % for inter-day precision. Limit of quantification (5.9 µg kg−1) is below the requested value of 10 µg kg−1. For some samples, it was superior to use a HILIC column compared with the originally used RP-18. Application to real samples (n = 87) showed nicotine concentrations in dry tea from <0.01 to 1.95 mg kg−1. In brewing studies of green teas and black teas, it was confirmed that the extraction of nicotine into tea brews was between 49 and 52 % for a steeping time of 5 min.