Separation of Nonivamide and Capsaicin by Ultrahigh-Performance Liquid Chromatography for Routine Analysis of Capsaicinoids in Capsicum Products

Abstract Background Baseline separation of nonivamide (NON) and capsaicin (CAP) has not been achieved by using the existing liquid chromatography (LC) methods for the capsaicinoid analysis. This could lead to large errors in the determination of capsaicinoids for capsicum products. Objective The development of an ultrahigh-performance liquid chromatography (UHPLC) method that simultaneously separates NON and CAP as well as other capsaicinoids for the routine analysis of capsaicinoids in capsicum products. Method Capsaicinoids were separated on a Waters CORTECSTM T3 Column (2.1 mm i.d. × 150 mm, 1.6 μm particle size) that was maintained at 45°C on a UHPLC system with a 3-step gradient elution using a binary mobile phase system consisting of water and acetonitrile. Florescence detection was set at 280 nm excitation wavelength and 325 nm emission wavelength. Results The UHPLC method was able to simultaneously separate NON and CAP, with a minimum resolution of 1.5, as well as other seven capsaicinoids with a total run time of 27 min. Method selectivity, robustness, accuracy, and precision were evaluated, and excellent performance was achieved. Conclusions The UHPLC method for NON and CAP and other seven capsaicinoids has been successfully developed and found suitable for the routine analysis of capsaicinoids. Highlights For the first time, NON and CAP are well separated (Rs >1.5) in a 27 min LC separation. This UHPLC method offers a suitable solution for the determination of nine capsaicinoids in QC labs.