Trace determination of glycols by HPLC with UV and electrospray ionization mass spectrometric detections.

A high-performance liquid chromatography/mass spectrometry (HPLC/MS) method is developed for trace determination of glycols (ethylene glycol, 1,2- and 1,3-propylene glycols, and 2,3-butylene glycol) in water after derivatization with benzoyl chloride. Benzoyl esters of glycols are separated by microcolumn reversed-phase HPLC. Sensitivity and linearity of UV detection at 237 nm is compared with electrospray ionization mass spectrometric (ESI-MS) detection using selected ion monitoring. Limits of detection (LOD) and quantitation (LOQ) for UV detection are 1 and 2 mg/L, respectively. For ESI-MS detection, LOD and LOQ are in the ranges 10-25 and 20-50 μg/L, respectively. LOD obtained by ESI-MS for the determination of glycols is improved by 2-3 orders of magnitude in comparison to previously published methods. The effect of the structure of isomeric glycols on their electrospray mass spectra is discussed. The method has been applied for the determination of glycols in aqueous matrixes containing high concentrations of salts occurring in nuclear waste disposal treatment.