Journal of Bioequivalence & Bioavailability

Abstract

Development and Validation of LC-MS/MS Method for Determination of Testosterone Level in Human Saliva Using Lovastatin as Internal Standard

Syed N Alvi, Saleh Al Dgither and Muhammad M Hammami

A rapid Liquid Chromatographic Tandem Mass Spectrometric (LC-MS/MS) assay for the measurement of testosterone level in human saliva was developed and validated using lovastatin as internal standard (IS). Retention times of testosterone and IS were around 3.2 and 3.8 min, respectively. Relationship between testosterone concentration and peak height ratio of testosterone to IS was linear (R 2 ≥ 0.98) in the range of 20-400 pg/ml, and the intra- and inter-day coefficient of variations (CV) were 4.7% to 9.5% and 6.5% to 11.3%, respectively. Quantification and detection limits were 20 and 10 pg/ml, respectively. Mean extraction recoveries were 80-93% for testosterone (four levels) and 81% for the IS. Stability of testosterone was determined under various conditions generally encountered in the clinical laboratory. The method was also successfully applied to determine testosterone level in saliva obtained from healthy subjects.