Detection of selected stimulants as contaminants in solid nutritional supplements by liquid chromatography–mass spectrometry

Nutritional supplements are frequently used by athletes and can contain substances banned by the World Anti Doping Agency (WADA). The aim of this study was to develop a screening method for the detection of selected stimulants in solid nutritional supplements. Analysis of the samples was performed on an LCQ-Deca® instrument after an acidic wash with n-pentane and an alkaline liquid/liquid extraction with diethylether. The mass spectrometer was operated in full scan MS2 using positive ionisation. Detection limits (LODs) were equal or below 50 ng/g for all compounds except strychnine (100 ng/g). The suitability of the method for routine application was illustrated by the analysis of two suspicious samples.