A novel approach for sensitivity enhancement in atmospheric pressure chemical ionisation liquid chromatography/mass spectrometry of chlorophylls

Differences in the ionisation efficiency of chlorophylls and their phaeophy tin counterparts result in lower sensitivity for atmospheric pressure chemi cal ionisation mass spectrometric detection of the former. Improvement in t he sensitivity of detection of chlorophyll of around an order of magnitude at a concentration of 1 x 10(-6)mol L-1 has been achieved using post-column addition of methanoic acid during analysis by liquid chromatography/mass s pectrometry (LC/MS), The method gives linear response and is a simple strat egy to improve sensitivity both for LC/MS and LC/MS/MS without loss of info rmation relating to the precise nature of the tetrapyrrole distributions. D etection levels achieved exceed those obtained by absorbance detection. Cop yright (C) 2000 John Wiley & Sons, Ltd.