Validation of an HPLC-HR/MS method for the determination and quantification of six drugs (morphine, codeine, methadone, alprazolam, clonazepam and quetiapine) in nails.

Keratinized matrices, including nails, are among the most resistant matrices that can be analyzed in cases where remains are deeply decomposed and relatively non -invasive for living people. In order to exploit these new matrices in the search for exogenous substances, it is necessary to develop analytical technologies capable of achieving high levels of sensitivity. In this technical note, an easy method is presented for the simultaneous extraction and quantification of three narcotic substances (morphine, codeine, methadone), two benzodiazepines (BDZ) (clonazepam and alprazolam) and an antipsychotic (quetiapine) from nail matrix by analysis in Ultra High-Performance Liquid Chromatography at High Resolution Mass Spectrometry (HPLC/HR-MS). The method has been validated following the Standard Practices for Method Validation in Forensic Toxicology of the Scientific Working Group for Forensic Toxicology. Nail specimens from eight authentic postmortem cases and thirteen living donor samples were extracted and analyzed. Of the eight postmortem samples, five resulted positive for at least one of the three substances searched. Ten of the thirteen living donor specimens were positive for at least one of the targeted benzodiazepines or quetiapine.