A technique for the identification and direct analysis of hexahydro-1,3,5-tris(2-hydroxyethyl)-s-triazine in metalworking fluids using electrospray-mass spectrometry

Abstract

Hexahydro-1,3,5-tris(2-hydroxyethyl)-s-triazine is a widely used biocide in metalworking fluids that resists direct quantification in many analytical methods due to instability. It can be detected in electrospray-mass spectrometry (ES-MS) due to the formation of a charged and relatively stable adduct with the sodium ion. This adduct produces a distinct ion spectrum via collision-induced fragmentation, which should promote specific detection of the analyte in complex matrices. ES-MS detection of the analyte added to, or already present in, metalworking fluid samples at µg mL⁻¹ levels is demonstrated. Parameters affecting the formation and detection of the sodium adduct, including choice of solvent, alkalinity, and sodium ion level are explored. Linearity of response in flow injection mode is demonstrated.