Low‐temperature derivatization followed by vortex‐assisted liquid–liquid microextraction for the analysis of polyamines in Nicotiana Tabacum

Polyamines are ubiquitous polycationic molecules that play a key role in many biological processes such as nucleic acid metabolism, protein synthesis, cell growth, and nicotine synthesis precursors. This work describes a rapid, sensitive, convenient, green, and cost‐effective method for the determination of polyamines in Nicotiana tabacum by ultra high performance liquid chromatography with photodiode array detection. The analytes were derivatized with 3,5‐dinitrobenzoyl chloride at low temperature (about 4°C) and then extracted with vortex‐assisted liquid–liquid microextraction. The experimental designs based on quarter‐fractional factorial design and Doehlert design were used to screen and optimize the important factors in microextraction process. Under the optimal conditions, the method was linear over 0.05–8.00 μg/mL with an r² ≥ 0.992 and exhibited good repeatability and reproducibility less than 6.0 and 6.9%, respectively. The limit of detection ranged between 0.013 and 0.029 μg/g. The newly developed method was successfully employed to analyze different leaf samples of Nicotiana tabacum, among which the polyamines contents were found to be very different. Moreover, tyramine, 1,3‐diaminopropane, homospermidine, and canavalmine were tentatively identified with the electrospray ionization quadrupole time‐of‐flight mass spectrometry. To our knowledge, this is the first report of identification of canavalmine in Nicotiana Tabacum.