A comparison of thermospray and direct liquid introduction high-performance liquid chromatography/mass spectrometry...

The analysis of antimalarials by high-performance liquid chromatography (HPLC)/mass spectrometry demonstrates a new dimension in specificity along with increased sensitivity compared to conventional HPLC detection methods. Both direct liquid introduction and thermospray HPLC/mass spectrometry interfaces provided molecular weight information as well as characteristic fragment ions for antimalarials not normally amenable to direct probe or gas chromatographic/mass spectrometric techniques. The direct liquid introduction interface, which incorporated a 1/100 split, showed a detection limit of 30 ng using selected ion monitoring. The thermospray technique showed less than 1 ng detection limits using selected ion monitoring.