Matrix-assisted laser desorption/ionization mass spectrometry for the rapid and high throughput analysis of betaine and trigonelline in Lycium chinense Mill. and trigonelline in coffee

A rapid, simple, effective, and green method for the determination of betaine and trigonelline from Mill. (LCM) and the quantification of the trigonelline in coffee was proposed and validated by matrix-assisted laser desorption ionization time-of-flight mass spectrometric (MALDI-TOF MS) detection. Due to without chromatographic separation, the method greatly shortened the detection time. The detection of betaine and trigonelline concentration showed good linearity in the range of 1–100 μg/mL and 0.01–100 μg/mL, with correlation coefficients r = 0.9962 and 0.9946, respectively. The good reproducibility and reliability of the method were demonstrated by excellent intraday and interday precisions with RSD <8.3%, and the recovery of betaine and trigonelline ranged from 92.2% to 116.0%. Analysis of LCM and coffee extracts (raw, light-roasted, and dark-roasted coffee beans) gave results in agreement with the literature. The method appeared as a fast and reliable alternative method for routine and coffee analysis.