2D NMR detection and quantification of heroin in a street sample

Two-dimensional nuclear magnetic resonance (2D NMR) spectroscopy was evaluated for the identification and quantification of compounds in an unknown street drug sample. Using 2D COSY and HSQC techniques, heroin was successfully quantified, and the presence of 6-monoacetylmorphine (6-MAM), xylazine, and caffeine was confirmed through partial structural elucidation. These methods demonstrated the ability to differentiate structurally similar opioid analogues without reliance on reference library databases. While gas chromatography–mass spectrometry (GC–MS) remains the standard in forensic laboratories, it has limitations in de novo structural analysis and in detecting emerging analogues absent from spectral libraries. In this study, heroin and fentanyl were quantified in both simulated and actual street samples at concentrations ranging from 0.97 to 1.80 mg/mL, with errors between 0 % and 34 % using a 400 MHz NMR instrument. A benchtop 60 MHz NMR system also detected and quantified 56 mg/mL of heroin with a 24 % error in a simulated sample. These findings support the complementary role of 2D NMR spectroscopy in forensic drug analysis in light of the opioid epidemic and the evolving drug market.