Abstract:

A fast screening method was established for the simultaneous determination of 24 sedative hypnotics illegally added in improving sleep health foods by high performance liquid chromatography-ion trap mass spectrometry (HPLC-IT MS). The method was based on the sonication assisted extraction of the improving sleep health food samples using methanol. The extract was then filtrated with 0.45 μm filter membrane and the filtrate was separated on a Phenomenex Luna C18 column with isocratic elution at a flow rate of 0.3 mL/min. A binary mobile phase was 0.05% (v/v) formic acid (solvent A)-methanol/acetonitrile (15:25, v/v, solvent B). The electrospray ionization (ESI) source in positive ion mode or negative ion mode was used to scan MS¹-MS³ spectra for the 24 sedative hypnotics. The MS² and MS³ spectra were used for qualitative analysis of samples. The calibration graphs were linear in their concentration ranges with the correlation coefficients (r²) more than 0.999. The limits of detection (LODs) were 4.0-446.6 μg/L. The recoveries for all the drugs in the improving sleep health foods were 88.6%-110.3% with the relative standard deviations no more than 9.8% at three spiked levels. Twenty-seven batches of the improving sleep health foods were tested. Melatonin was found in eighteen batches. The method is fast, specific, sensitive, easy and suitable for fast screening of 24 sedative hypnotics illegally added in improving sleep health foods.

Key words: fast screening, health foods, high performance liquid chromatography-ion trap mass spectrometry (HPLC-IT MS), sedative hypnotics