Analysis of conjugated steroid androgens: Deconjugation, derivatisation and associated issues

Abstract

Gas chromatography/mass spectrometry (GC/MS) is the preferred technique for the detection of urinary steroid androgens for drug testing in athletics. Excreted in either the glucuronide or sulfated conjugated form, steroids must first undergo deconjugation followed by derivatisation to render them suitable for GC analysis. Discussed herein are the deconjugation and the derivatisation preparative options. The analytical challenges surrounding these preparatory approaches, in particular the inability to cleave the sulfate moiety have led to a focus on testing protocols that reply on glucuronide conjugates. Other approaches which alleviate the need for deconjugation and derivatisation are also highlighted.

Steroid bioaccumulation profiles in typical freshwater aquaculture environments of South China and their human health risks via fish consumption

“…the free and conjugated forms (glucuronides and sulfates) (Mota et al, 2014). When entering the pond of F3, some residual conjugated steroids are likely deconjugated into free forms (Gomes et al, 2009) or converted from some other steroids with similar molecular structures (Egorova et al, 2009;Jenkins et al, 2004). Ten synthetic steroids were detected in water samples of the aquaculture farms (Table 1).…”

Steroids in a typical swine farm and their release into the environment

“…Some of the steroids are excreted from livestock in the conjugated forms (glucuronides and sulfates) (Gadd et al, 2010;Hanselman et al, 2003). After entering into the receiving stream, some residual conjugated steroids are likely transformed into free steroids along the stream water by b-glucuronidase and sulfatase enzymes, which are released by E. coli w a t e r r e s e a r c h 4 6 ( 2 0 1 2 ) 3 7 5 4 e3 7 6 8 or conversion from some other steroids with similar molecular structures (Das et al, 2004;Gomes et al, 2009;Lee et al, 2003;Ternes et al, 1999b). It is worthy to notice that 17a-ethynyl estradiol was not detected in the receiving stream (1000 m downstream) although it was detected at a concentration of 195 AE 59.8 ng/L in lagoon 2 wastewater.…”

Development of a rapid column-switching LC-MS/MS method for the quantification of THCCOOH and THCCOOH-glucuronide in whole blood for assessing cannabis consumption frequency

“…Numerous analytical methods for the quantification of THC and its metabolites in biological fluids have been developed, which are mostly based on gas chromatography (GC) or liquid chromatography (LC) coupled to mass spectrometry (MS) [23,24]. However, the direct and simultaneous determination of THCCOOH and its glucuronide by GC-MS is not possible as glucuronides are thermally unstable and non-volatile [25,26]. To quantify THCCOOHglucuronide by GC-MS, free THCCOOH is analyzed first and then the glucuronide is hydrolyzed to measure total THCCOOH.…”