Tandem mass spectrometry linked fraction collection for the isolation of drug metabolites from biological matrices.

An automated mass spectrometric linked fraction collection system is described which enables on-line examination of isolated components based on molecular-ion and product-ion information. This system has been used successfully to specifically isolate drug-related material from complex biological fluids to aid structural identification. Metabolites have been isolated with sufficient purity to allow unequivocal characterisation by 1H nuclear magnetic resonance spectroscopy. This system has the advantage that isolation of the components of interest is not triggered by a simple contact closure. Therefore fraction collection is not biased by limitations in either the detector (e.g. insufficient sensitivity) or the analyst (e.g. programmed collection of predicted metabolites only). Furthermore, all isolated components are readily available post fractionation for additional screening.