USEFULNESS OF THE STOPPED-FLOW MIXING TECHNIQUE FOR MICELLE-STABILIZED ROOM-TEMPERATURE LIQUID PHOSPHORIMETRY

The stopped-flow mixing technique was applied for the first time to mi celle-stabilized room-temperature phosphorimetry by measuring the fast appearance of the phosphorescent signal yielded by carbaryl in the pr esence of sodium dodecyl sulfate and thallous ion. The slope and ampli tude of the kinetic curves obtained are directly proportional to the a nalyte concentration, which allows one to develop very simple, fast, a utomatic methods for the phosphorimetric determination of dissolved ca rbaryl without the need for solid substrates. Kinetic and equilibrium data can be obtained within only 2-3 s with a greater precision than t hat provided by solid-surface room-temperature phosphorimetry. The cal ibration graphs obtained for the proposed kinetic and equilibrium stop ped-flow method were linear over the range 0.030-2.0 and 0.050-3.0 mu g mL(-1) carbaryl, respectively, and the detection limits achieved wer e 0.010 and 0.014 mu g mL(-1), respectively, ie., lower than those pro vided by solid substrates.