The quantitative detection of HO˙ generated in a high temperature H2O2 bleaching system with a novel fluorescent probe benzenepentacarboxylic acid

Abstract

A novel fluorescent probe, benzenepentacarboxylic acid (BA), was developed for the quantitative detection of hydroxyl radicals (HO˙) in a simulated hydrogen peroxide (H₂O₂) bleaching system. Compared to terephthalic acid (TA), a commonly-used fluorescent probe of HO˙ with four possible reaction sites, the present probe has only one reaction site for HO˙ addition that results in the formation of a single fluorescent product, hydroxybenzenepentacarboxylic acid (HBA). The generation of the single pure fluorescent product by BA, rather than mixtures by TA, made the present probe more sensitive, accurate and reproducible in the quantitative detection of HO˙. Based on the working curve obtained from the fluorescence intensity and HBA concentration, a fluorimetric method for the quantitative detection of HO˙ was developed. The present probe BA was successfully used for the quantitative detection of HO˙ under alkaline and high temperature (80 °C) conditions, in a simulated H₂O₂ bleaching system. The method was highly sensitive, reproducible, and applicable in a wide temperature range of 20–98 °C. The present novel fluorescent probe will be potential tool for evaluating the generation and function kinetics of HO˙ generated in biological and environmental fields.