Rapid characterization of drugs in a single hair using thermal desorption ionization mass spectrometry

Abstract

Hair remains the most common type of physical evidence found in most crime scenes. However, the amount of hair found at a crime scene is limited and analysis of drugs in hair by gas chromatography mass spectrometry (GC-MS) or liquid chromatography tandem mass spectrometry (LC-MS/MS) is laborious and time-consuming. In this study, a rapid and simple method is developed using thermal desorption ionization mass spectrometry (TDI-MS) to analyze drugs directly in a single hair. A single hair is put onto a heated metal ceramic heater (MCH) and then a high voltage direct current and solvent are applied to the single hair. The drugs in the hair are thermally desorbed and ionized, and subsequently transferred to the MS inlet and detected. A typical hair analysis can be completed in a few minutes. This novel technique provides a new orientation for forensic scientists to study drugs in a single hair that is found at a crime scene, on a suspect, or on a victim.