Elevated urinary cobalt concentrations identified in routine doping controls can originate from vitamin B12 / Andre Knoop, Christian Görgens, Hans Geyer, Mario Thevis. - (Rapid Communications in Mass Spectrometry 34 (2019) 7 (15 April); p. 1-3)
- DOI: 10.1002/rcm.8649
Cyanocobalamin was unequivocally identified in the doping control urine sample by HRMS. The intact molecular ion was observed in full‐MS measurements, and diagnostic product ions obtained by collision‐induced dissociation were detected and matched previous publications.21 It is noteworthy that a concentration of 565 ng/mL was calculated using the prepared calibration curve, computed by signal area ratios of the target analyte and the employed internal standard (fivefold deuterated isoxsuprine, ISTD).
The presented data indicate the importance of the careful assessment of total urinary cobalt concentrations in the context of routine sports drug testing programs and, potentially, also in other clinical applications. The determination of inorganic cobalt and the differentiation from cyanocobalamin can be accommodated by simple SPE‐based depletion of the cobalt‐containing organic molecule and subsequent analysis of the extract's flow‐through by ICP‐MS. Alternatively, routine tests by means of LC‐ICP‐MS and/or concomitant analyses of urine samples for vitamin B12 are recommended for adequate result interpretation and management.