Determination of hydrolysis products of sulfur mustards by reversed-phase microcolumn liquid chromatography coupled on-line with sulfur flame photometric detection and electrospray ionization mass spectrometry using large-volume injections and peak compression

On-line coupling of reversed-phase microcolumn liquid chromatography (micro -RPLC) and sulfur-selective name photometric detection (S-FPD) was studied for the selective and direct determination of thiodiglycol, bis(2-hydroxyet hylthio)methane, 1,2-bis(2-hydroxyethylthio)ethane, 1,3-bis(2-hydroxyethylt hio)propane, and 1,4-bis(2-hydroxyethylthio)butane, which are breakdown pro ducts of the chemical warfare agents called sulfur mustards, Both isocratic and gradient elution were used. To improve sensitivity, large-volume injec tions were applied together with peak compression by displacement for late- eluting analytes, With S-FPD, detection limits of 1 mu g/mL were obtained f or all compounds. Using the same approach, the target analytes as well as v arious oxidation products could be identified by micro-RPLC with electrospr ay ionization mass spectrometry (ESI-MS) and ESI-MS/MS. The optimized micro -RPLC-S-FPD system was successfully used for the analysis of a spiked soil sample.