PURPOSE In this study, selective androgen receptor modulators(SARMS)
and their metabolites were investigated by using liquid chromatography
quadrupole mass spectrometry (lc-ms/MS)and liquid chromatography
quadrupole time-of-flight mass spectrometry (lc-qtofms). This research
provided a technical support for detection of SARMS in doping
controlMETHODS Liquid liquid extraction (LLE)method: One milliliter
of urine was placed in a glass tube and buffered to ph 7.0 with 1 ml of
a 0. 8M phosphate buffer. Fifty microliters of b-glucuronidase from
E coli and 100 ng of 17 a-methyltestosterone, an internal standard were
added, and the sample heated at 55C for 1 h. After cooling to ambient
temperature, 0 5ml of an aqueous solution containing potassium carbonate
and potassium bicarbonate plus 4 ml of methyl tert-butyl ether were added,
The organic layer was transferred to a fresh glass tube, flowed to dryness
at 55C, and the dry residue dissolved in 100ul of mobile phase, injected
for lc-ms-ms analysis. Solid phase extraction (SPE)method: Waters
sep-pak C18 column were washed by 3ml water and 3ml methanol. One
milliliter of rat urine were applied on the column. The methanol section
llected and evaporated to dryness at 55C afte washing by 3ml
water and methanol. The dry residue was dissolved in 150ul of mobile phase,
injected for lc-qtofms analysis RESULTS AND DISCUSSION The limits of
detection (LODS)were all below 2 u g/L. The recoveries were all higher
than 60%. The intra-day and inter-day rsds were all less than 20%. Three
new andarine metabolites, eighteen new ostarine metabolites and eleven
new lgd-4033 metabolites were found respectively in rat urine.
CONCLUSIONS New method for simul taneous detection of 7 selective
androgen receptor modulators (SARMS)was developed and validated. It
proved to be effective by testing 200 routine samples.