KINETIC DATA FROM INDIVIDUAL PEAK PROFILES CORRECTED FOR DISPERSION IN FLOW-INJECTION ANALYSIS APPLIED TO THE DETERMINATION OF ALUMINUM

A new procedure for obtaining analytical kinetic Information in single-line flow infection analysis (FIA) system is described. A microcomputer-controlled FIA system Is first used to acquire and store the peak profiles of a nonreactlng reference solution and a reacting sample solution. Next the sample FIA response is normalized in the time domain by multiplying the signal response by the relative sample dispersion coefficients calculated from the reference profile. in the absence of a chemical reaction, the normalized sample profile is flat. When the slow chemical reaction is in progress during the time between injection and detection, the signal varies across the normalized profile and analytical kinetic information can be extracted under certain conditions. Chemical and instrumental variables were optimized for a fluorometric kinetic determination of Al3+ with the fixed-time method. A 13 ng/mL detection limit was achieved. The proposed method Is shown to discriminate against the Interference from riboflavin, a nonreactlng fluorescent species. © 1990, American Chemical Society. All rights reserved.