RECENT DEVELOPMENTS IN ELECTROSPRAY MASS-SPECTROMETRY INCLUDING IMPLEMENTATION ON AN ION-TRAP

Mass spectrometry (MS) may be the ultimate detection technique when co mbined with modern condensed phase separation sciences. The technique combines sensitivity with excellent specificity, so the pharmaceutical analyst can obtain definitive information regarding components separa ted in a mixture. Thus, mass spectrometric detection not only provides evidence of a chromatographic peak, but it also provides important in formation including molecular weight and structural information enabli ng identification of the components. The coupling of an atmospheric pr essure ionization (API) mass spectrometer to most of the separation sc ience techniques offers a simpler alternative from earlier nonroutine, less sensitive systems where the vacuum systems struggled to handle t he liquid effluent from these systems. Contemporary sensitive and anal ytically rugged API systems can be operated unattended for extended pe riods of time thus reducing the cost per sample to a reasonable value especially given the wealth of information provided. Although the mass spectrometer is more complicated than conventional spectroscopic dete ctors, present day API systems effectively decouple the liquid-phase s eparation inlet from the high-vacuum system where mass analysis occurs . The ability to form gas-phase ions at atmospheric pressure and sampl e primarily the analyte ions into the mass spectrometer promises a bri ght future for combining on-line condensed phase separation science te chniques with mass spectrometry. The increasing ease of performing the se experiments offers new analytical opportunities for pharmaceutical laboratories.