Analytical Sciences


Abstract − Analytical Sciences, 16(4), 397 (2000).

The Use of Triton X-100 in Thermal Lensing of AqueousSolutions
Mikhail A. PROSKURNIN, ۷era B. IVLEVA, Nataliya Yu. RAGOZINA, and Elena K. IVANOVA
Analytical Chemistry Division, Chemistry Department, M. V. Lomonosov Moscow State University,Vorob'evy Hills, Moscow, GSP-3 V-234, 119899, Russia
The ability of Triton X-100 to affect thermooptical parameters of water is used for determining the surfactant by thermal lensing. The limit of detection of Triton X-100 in the presence of pre-synthesized cobalt(III) tris-(2-nitroso-1-naphtholate) as an inert colorant is 8x10-4 mol dm-3, which is close to the critical micelle concentration of the surfactant. A method for estimating the limits of detection of thermal lensing in a given solvent system based on the reproducibility of measurements for a single sample is developed. In this approach, Triton X-100 is applied for enhancing the sensitivityof thermal lensing in aqueous solutions. For the concentrations of Triton X-100 of 0.04 - 0.1 mol dm-3, a twofold enhancement in detection limits of iron(II) with 1,10-phenanthroline and cobalt(III) with 2-nitroso-1-naphthol as model systems without any change in the sample preparation is observed.