Fluorescent dyes bound to hydrophilic copolymers: Applications in aqueous halide sensing

A range of halide-sensitive fluorophores were bound to two hydrophilic copo lymers. Thin films of the copolymers swelled in the aqueous media, allowing dye fluorescence to be dynamically quenched by the diffusion of halide ion s. The resultant sensor films were characterized in terms of their hydrophi licity, sensitivity, and selectivity toward halide. The sensor films were r eversibly capable of determining aqueous bromide and iodide at a mildly alk aline pH with typical 90% response times of 30-70 s and a shelf life in exc ess of 2 years. (C) 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 603-6 15, 2000.