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Volumetric absorptive microsampling (VAMS) and dried urine spot (DUS) strategies were applied for the collection of dried microsamples for anti-doping testing of low-stability peptide hormones and growth factors prohibited by the World Anti-Doping Agency (WADA). Drying, storage and transport conditions, as well as pretreatment steps, were optimised before liquid chromatography - tandem mass spectrometry (LC–MS/MS) analysis. The analytical method has been fully validated in terms of sensitivity (limits of quantitation 0.3−10 ng/mL), precision (RSD% < 6.6 %) and extraction yields (78–91 %). Dried microsample stability studies (90 days) have been performed and compared to fluid urine stability. Significantly higher losses have been observed in fluid urine stored at −20 °C (up to 55 %) and −80 °C (up to 29 %) than in dried urine microsamples stored at room temperature (< 19 %). The final microsampling and analysis protocols allow the collection of urine microvolumes, unlikely to be tampered, stably storable and shippable with no particular precautions for possible anti-doping testing of prohibited peptides and hormones.

Synthetic cannabinoids are new psychoactive substances (NPS) with similar effects when compared to natural ones found in Cannabis derivatives. They have rapidly integrated into the illicit market, often sold as alternatives under international control. The need to identify and quantify an unprecedented and growing number of new compounds represents a unique challenge for toxicological, forensic and anti-doping analysis. Dried blood spots have been used within the bioanalytical framework in place of plasma or serum, in order to reduce invasiveness, lower sample size, simplify handling, storage and shipping of samples and to facilitate home-based and on-field applications. However, DBS implementation has been limited mainly by concerns related to haematocrit effect on method accuracy. Volumetric absorptive microsampling (VAMS™), a second generation dried miniaturized sampling technology, has been developed just in order to eliminate haematocrit effect, thus providing accurate sampling but still granting feasible sample processing. An original LC-MS/MS method was herein developed and validated for the analysis of THC and its 2 main metabolites, together with 10 representative synthetic cannabinoids in both DBS and VAMS dried microsamples. The ultimate goal of this work is to provide highly innovative DBS and VAMS analytical protocols, whose performances were extensively optimized and compared, in order to provide effective and alternative tools that can be applied for natural and synthetic cannabinoid determination, in place of classical analytical strategies.

In the last few years, several cathinone analogues have appeared on the illicit drug market and proposed as an alternative to already known stimulants in several recreational settings. The World Anti-Doping Agency classified the synthetic cathinones in the Prohibited List as specified stimulants, banned in sport competitions. We developed and validated an LC-MS/MS method for the analysis of methylone, ethylone, butylone, mephedrone, 4-methylethcathinone and 3,4-methylenedioxypyrovalerone in dried urine, plasma and oral fluid samples. Volumetric absorptive microsampling has been employed as a miniaturised sampling technique for collecting dried biological samples. Chromatographic analysis was carried out on a C18 reversed phase column with a mobile phase composed of formic acid in a water/acetonitrile mixture, by using a triple quadrupole mass analyzer. The main parameters of the volumetric absorptive microsampling procedure were investigated and the method was fully validated with satisfactory results in terms of linearity, precision, absolute recovery, matrix effects, selectivity and stability. The method was successfully applied to real samples collected from cathinones users. The biosampling strategy via volumetric absorptive microsampling for urine, plasma and oral fluid could provide reliable information, with a future perspective of implementation for forensic cases as well as for sport drug testing.