Drug screening method development for paper spray coupled to a triple quadrupole mass spectrometer

Paper spray mass spectrometry is a direct analysis method in which compounds are extracted and ionized from biofluids dried on paper. It is an attractive option for performing rapid drug screening because it is fast (the entire sample analysis takes < 2 minutes), simple (there is no sample preparation or chromatography), and sensitive (low ng mL(-1) levels of many drugs can be detected from dried blood spots). Here, we discuss method development for paper spray mass spectrometry on a triple quadrupole mass spectrometer. Specifically, detection criteria, selected reaction monitoring (SRM) ratio tolerance, fragment ion selection, selectivity, and signal to blank considerations are all addressed. 134 drugs and drug metabolites commonly encountered in forensic toxicological analyses were spiked into blood at concentrations reasonable for post-mortem drug screening applications. Detection of some 130 drug and drug metabolites using a single paper spray MS/MS is shown for these spike and recover experiments.