Dried microsamples: Multi-matrix, long-term stability study of doping-relavant peptides (WADA 2019)

Microsampling provides a wide range of applications that may offer advantages over traditional fluid samples on logistics and bioanalytical workflow. Among microsampling methods, dried matrix spots (DMS) represents a feasible method for the microsampling of biological matrices to obtain dried urine spots (DUS), dried blood spots (DBS), dried oral fluid spots (DOFS) and dried sweat spots (DSS). Moreover, volumetric absorptive microsampling (VAMS) has been recently introduced for the sampling of small, accurate biological fluid volumes. Dried microsamples can usually be stored under ambient conditions, although comprehensive analyte stability assessments are still under research for many compounds. Following the promising results previously obtained from the definition of mid-term stability of some doping-relevant peptides (e.g. GnRH analogues) in urine collected as DUS and VAMS, aim of this research is to carry out a systematic study on the long-term stability of such compounds in urine, blood, oral fluid and sweat sampled as DMS and VAMS and to expand the study to additional GnRH analogues, mitochondrion‐derived peptide MOTS‐c, body protection compound BPC-157, variant of mechano-growth factor MGF R23H and novel haemoglobin-based oxygen carriers (HBOCs). All variables involved in the sampling process will be assessed: humidity, temperature, light exposure will be evaluated to determine the optimal sampling, storage and transport conditions, and to evaluate results obtained from microsamples. In addition, possible scenarios will be simulated, representing the life cycle of an anti-doping sample: from collection to shipment, storage and handling before being subjected to pretreatment procedures and LC-MS/MS and LC-HRMS analysis. The project goal is to establish feasible and reliable workflows for microsample collection, stably storable and shippable with minimum precautions. These procedures could then be proposed as effective anti-doping strategies to be compared to conventional fluids.