Application of tryptamine as a derivatising agent for airborne isocyanates determination. Part 1. Model of derivatisation of methyl isocyanate characterised by fluorescence and amperometric detection in high-performance liquid chromatography

Abstract

Tryptamine was investigated as a derivatising agent for the determination of airborne isocyanates. A model compound was prepared by derivatising methyl isocyanate with tryptamine. The former is the simplest isocyanate in structure and was easily vaporised, resembling most airborne isocyanates in the workplace while simulated air sampling was conducted. Tryptamine contains an indolyl moiety and undergoes fluorescence and amperometric oxidation.Reversed-phase high-performance liquid chromatographic separation was employed for the isocyanate derivative in conjunction with dual detection characterised by fluorescence and amperometric oxidation. Both detection methods were highly specific with similar sensitivities. Therefore, this method would also provide the desired information for confirmatory purposes in addition to the extremely low level of quantification.