ABSTRACT
OBJECTIVE:To determine the concentration of dehydroisoandrosterone sulfate (DHEAS) in human plasma by LC-MS.METHODS:With estrogen sulfate (ES) served as an internal standard,the plasma samples were deproteinized with acetonitrile,extracted by solid phase,hydrolyzed and derivatized.Then the concentration of DHEAS was determined by HPLC-MSD on Agilent SB C18 with column temperature kept at 40℃.The mobile phase consisted of acetonitrile-water (in gradient elution).Atmosphere pressure chemical ion source in negative ion detection model was employed.The ions selected for SIM (selected ion monitoring) quantitative analysis included m/z 490.0 (DHEAS ) and m/z 472.1(ES)[M-H]-.RESULTS:The linear range of DHEAS was 250.0～320.0 ng?mL-1(r=0.999 4).The extraction recovery of the simulated human albumin samples ranged from 71.1%～78.9% and its relative recovery ranged from 98.3%～101.4%.Both the intra-day RSD and inter-day RSD were less than 10%.The mean concentration of DHEAS in 15 health aged male volunteers was (981.6?353.4) ng?mL-1.CONCLUSION:The method is simple,practical,accurate and sensitive,and it is applicable for the determination of plasma concentration of DHEAS.