1 Department of Pharmacognosy and Phytotherapy, Faculty of Pharmacy, George Emil Palade University of Medicine, Pharmacy, Science and Technology of Târgu Mureș, Romania
2 Chromatography and mass spectrometry laboratory, Center for Advanced Medical and Pharmaceutical Research, George Emil Palade University of Medicine, Pharmacy, Science and Technology of Târgu Mureș, Romania
Tribulus terrestris L. (TT) became a very popular plant due to its effects in sexual disorders. The pharmacological actions seem to be related with its content in sterolic saponins. Protodioscin has been reported to be the main compound from TT products with anabolic effects. Because of the popularity of the plant, numerous herbal supplements are consumed around the world. Quantification of steroidal saponins through HPLC methods is sometimes difficult. Several methods have been proposed but not all are reproducible. The aim of this study was to validate a LC MS/MS method for quantification of protodioscin in herbal supplements. Two herbal supplements found on the Romanian market have been chosen for this study. The compounds were separated on a C18 column with ammonium acetate buffer and acetonitrile as mobile phase. The ionization was performed in electrospray negative mode and detection of protodioscin was made by monitoring the sum of ions m/z 737.41, m/z 739.42 and m/z 755.42. In one of the herbal supplements, protodioscin was under the limit of quantification. In conclusion a simple and rapid method is proposed for the quantification of protodioscin in herbal supplements.