Investigation of the applicability of dried blood spots for the analysis of glucocorticoids

Code: 242C03WCWC

Glucocorticoids (GCs) are widely used in medicine among athletes and are prohibited in competition only when administered orally, rectally, or by injection. However, an in-competition urine sample may show GC levels above the established laboratory reporting levels even if the administration occurred out-of-competition. Urinary washout periods have been established to mitigate this risk. Since blood levels correlate better with substance exposure than urine, dried blood spots (DBSs) collected through microsampling may provide valuable support in determining the timing of GC administration.

This study aims to investigate and compare the concentration changes of GCs in DBSs and urine during the washout period following GC administration. A rapid and sensitive UPLC-MS/MS-based method has been developed for the simultaneous quantitation of six common GCs in DBSs, with the extraction procedure optimised to ensure favourable recoveries. DBSs and urine samples are then collected from subjects receiving oral prednisolone, intramuscular dexamethasone, and locally injected triamcinolone acetonide. The pharmacokinetics and detection windows of each GC in DBSs are established, and reference ranges are suggested. The DBS data are compared with those from urine. The developed analytical method and the resulting elimination datasets are readily deliverable to anti-doping labs and authorities, enhancing the applicability of DBS for GC testing.