Quantitative analysis of desomorphine in blood and urine using solid phase extraction and gas chromatography-mass spectrometry.

Desomorphine, a semi-synthetic opioid, is a component of the street drug Krokodil. Despite continued reports of Krokodil use, confirmation via toxicological testing remains scarce. The lack of confirmed desomorphine reports may be in part due to the limited published analytical methodology capable of detecting desomorphine at forensically relevant concentrations. In an effort to assist with identification efforts, a robust analytical method was developed and validated. Solid phase extraction (SPE) and gas chromatography-mass spectrometry (GC-MS) were used to determine desomorphine in blood and urine using a deuterated analog as the internal standard. Data was acquired using selected ion monitoring (SIM) mode. Extraction efficiencies in blood and urine were 69% and 90%, respectively. The limits of quantitation in blood and urine were 5 ng/mL and 8 ng/mL, ten-fold lower than previously published methods. Intra- and inter-assay CVs were 2-4% (n = 3) and 3-7% (n = 15), respectively. The method was fully validated in accordance with published guidelines for forensic use. Furthermore, it provides a means by which desomorphine can be identified in toxicology specimens at forensically relevant concentrations, without the need for derivatization.