“…In modern clinical laboratories, LC-MS/MS has become the preferred platform for analyzing endogenous sex hormones ( 4 ). Numerous methodologies have been developed recently ( 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 ). As excellently summarized in the latest reviews, to achieve profiling of sex hormones, most, if not all, of the published methods introduced liquid-liquid extraction (LLE) or solid phase extraction (SPE) for sample preparation ( 17 , 18 ).…”