Rapid screening of banknotes for the presence of controlled substances by thermal desorption atmospheric pressure chemical ionisation tandem mass spectrometry

The ability to thermally desorb directly particulate matter, trapped on fil ter meshes, into the atmospheric pressure chemical ionisation source of a t andem mass spectrometer allowed the simultaneous detection of a range of co ntrolled substances within complex matrices with a high degree of confidenc e. Dust samples were collected from bundles of banknotes using simple appar atus attached to a portable vacuum cleaner. This technique was employed wit hout additional clean-up procedures, rendering the overall method extremely rapid. The intensities recorded for characteristic gas phase ion transitio ns allow the determination of the amounts of contaminants present. It has b een reported that a significant proportion of bundles of banknotes are cont aminated with cocaine. This study found that cocaine and heroin (and two re lated opiates) were present above the detection threshold on UK banknotes f rom general circulation. Differences in both the frequency and degree of co ntamination were apparent between bundles of banknotes from general circula tion and those suspected of being associated with the trafficking of drugs. In addition, a significant number of bundles of banknotes, confiscated by H.M. Customs and Excise, were found to be contaminated with detectable leve ls of tetrahydrocannabinol and 3,4-methylenedioxymethylamphetamine.