Pilot Study: The analysis of known physical mixtures mimicking heroin samples using X Ray Powder Diffraction for the purposeof qualitative and quantitative analysis

The illegal use of drugs is a major issue, and it is estimated that globally 210 million people aged 15-64 had used an illicit substance at least once. Heroin is one of the most problematic drugs and there is a high fatality rate as a result. The increasing trend in global seizures suggests that there is an increase in production of heroin. Current drug analysis involves qualitative and quantitative determinations using techniques such as Gas Chromatography (GC) and/ or Liquid Chromatography- Mass Spectrometry (LC-MS). Profiling of suspected drugs requires a further evaluation of the chromatographic and spectroscopic data along with further testing. The use of XRPD for the purpose of drug analysis is rare in the field of Forensic Science. It is a non-destructive technique preserving the sample analysed for further investigation if required. This study aims to demonstrate the capability of X-Ray Powder Diffractometry as a tool for simultaneous qualitative and quantitative analysis of known physical mixtures mimicking heroin samples.

A suitable method was developed to analyse known mixtures containing caffeine, codeine and paracetamol using the Bruker D8 Advance X-ray diffractometer. Following this the method was optimised to improve the qualitative and quantitative capabilities. The data highlighted that a 20 minute runtime using a 0.020° increment size provided accurate and repeatable data using a 50:50 caffeine:paracetamol mixture. Rietveld refinement was used to enable quantitation and provided highly accurate and repeatable results through single (active) component quantitation in the presence of an internal standard over a range of 12.6% w/w to 50.1% w/w.