Chemiluminescence from fluorescent organic compounds induced by cobalt(II) catalyzed decomposition of peroxomonosulfate

Abstract

A new chemiluminescence (CL) system was developed for the detection of fluorescent organic compounds (FOCs). The CL system is composed of an oxidizing agent, peroxomonosulfate (KHSO 5) and a metal ion catalyst, cobalt (as sulfate). In unbuffered conditions, HSO − 5 is decomposed by Co 2+ to yield reactive species (Co 3+, SO − 4, etc.), which are strong oxidizing agents leading to CL from FOCs. The CL signal was strongly dependent on the mixing order of the reagents and observed on adding a FOC to a HSO − 5/Co 2+ mixture. Even in 30 min after the decomposition of HSO − 5, the addition of a FOC caused appreciable CL. The lower detection limits ( S/ N=3) were in the concentration range 10 −9–10 −7 M for FOCs such as polycyclic aromatic hydrocarbons, dyes and dansylated amino acids. The mechanistic study of the CL reaction was undertaken briefly. The present CL system was applied to the post-column detection of vitamin B 2 and amino acids in liquid chromatography.