APPLICATION OF CLOUD POINT EXTRACTION USE 1- (2-PYRIDYLAZO) -2- NAPHTHOL AND TRITON X-100 SPECIATION ANALYSIS OF MANGANESE IN TEA SAMPLES

Abstract

A simple, rapid, inexpensive, and nonpolluting cloud point extraction (CPE) technique has been improved for the preconcentration and determination of species manganese in tea infusion. The optimization step was performed involving the following variables: pH, concentration of 1-(2- pyridylazo)-2-naphtol (PAN) and Triton X-100 (TX-100), incubation temperature, incubation time and
ionic strength (with concentration NaCl). Under the optimized conditions, enrichment factor of 8,3 was achieved leading to limit of detection and limit of quantitation of 0.0308 and 0.0935 ppm, respectively.
In tea infusion, flavonoid bound Mn(II) and weakly complexed Mn(II) occupy for 6,05 – 15,3%, 84,7 – 93,95% respectively.