Abstract
The ability to determine the purity (% controlled compound) of drug‐of‐abuse samples is necessary for public health and law enforcement. Here, we describe the assessment of atmospheric solids analysis probe (ASAP) for the rapid determination of drug purity for a set of formulated pharmaceuticals, chosen due to their availability, uncontrolled status and consistency. Paracetamol and loratadine were used as models of high and low purity compounds being ~90% and ~10% active ingredient, respectively. Individual tablets were ground up and diluted in an internal standard solution. The resulting samples were analysed by ASAP coupled to a Waters QDa mass spectrometer followed by confirmatory testing by liquid chromatography–tandem mass spectrometry (LC–MS/MS). The inclusion of a non‐matched internal standard (quinine) improved linearity and repeatability of drug analysis by ASAP‐MS. Levels of drug purity using formulated pharmaceutical tablets were found to be highly comparable with results produced by the ‘gold standard’ LC–MS/MS technique. Rapid determination of drug purity is therefore possible with ASAP‐MS for highly concentrated samples with minimal sample preparation. It may be possible to use this deployable system to determine drug purity outside of a laboratory setting.