The Effect of Micelles on the Steady-State and Time-Resolved Fluorescence of Indole, 1-Methylindole, and 3-Methylindole in Aqueous Media

摘要

3-Methylindole (skatole) is a component of animal waste and is, consequently, a primary component in odor problems arising in livestock management, notably swine production. The ability to probe and to exploit the interactions of 3-methylindole with micelles has important implications for monitoring and controlling odor problems. The effect of a surfactant (Brij-35) on the fluorescence properties of indole, l-methylindole, and 3-methylindole in aqueous solutions is reported. Steady-state fluorescence spectra reveal a blue shift in the emission as the surfactant concentration is increased, while the absorption spectra are practically unaffected. Time-resolved fluorescence measurements reveal shorter aver. age lifetimes for 3-methylindole (3-MI) as the Brij-35 concentration is increased. The fluorescence decay of 3.MI in water is described well by a single exponential, whereas, at the highest Brij-35 concentration, a triple exponential is necessary to describe the fluorescence decay. The contributions of each component in the fluorescence decay are used to determine the extent of