Determination and analysis of opiates in complex mixtures by surface-ionization mass spectrometry

Abstract

The results of studies of the analytical opportunities of surface-ionization mass spectrometry (SIMS) for high-sensitivity and selective detection and analysis of opiate mixtures—natural opium, crude heroin, and narcotic analgesic omnopon—are presented. The experiments were carried out using an MX-1320 chemical mass spectrometer modernized for studying surface ionization (SI). It was ascertained that the opiate mixtures are ionized by highly efficient surface ionization. The bands of M+ (for papaverine), (M-H)+, (M-H-2nH)+, (M-R)+, and (M-R-2nH)+ ions, where M is a molecule, H is a hydrogen atom, R is a radical, are observed in the mass spectra; they are the sum of the SI mass spectra of components of the mixtures. The series of bands of ions with m/z of 144 and 146 that is characteristic of SI-morphinelike molecules is the main one in the mass spectrum of crude heroin, while for omnopon and natural opium this series is the main at low temperatures of a thermionic emitter (up to ∼900 K). At high temperatures of the thermionic emitter, the band series with m/z of 218 and 220 is the main series. Studies of natural opium, crude heroin, and omnopon have shown that the SIMS method allows analyzing mixtures without preliminary chromatographic separation thereof. The study also contains the results of comparative analyses of opiate mixtures by SIMS and chromate- and mass spectrometry (HP-6890) with electronic ionization.