SURFACTANT ENHANCED CHEMOFILTRATION OF ZINC TRACES PREVIOUS TO THEIR DETERMINATION BY SOLID SURPHASE FLUORESCENCE

VEGA, MABEL; AUGUSTO, MIRIAM; TALÍO, MARÍA CAROLINA; FERNANDEZ, LILIANA

American Jornal of Analytical Chemistry

Scientific Research Publishing Inc.

Año: 2011

2156-8251

<!-- @page { margin: 2cm } P { margin-bottom: 0.21cm } --> Surfactant enhanced chemofiltration on Nylon membranes pre-treated with hexadecyltrimethylammonium bromide (HTAB) and eosin dye (eo) is proposed for zinc traces quantification by solid surphase spectrofluorimetry (SSF, λexc = 532 nm; λem = 548 nm). Operational variables which have influence on quantitative retention of metal complex have been studied and optimized. At optimal experimental conditions, quantitative recovery was reached with a detection limit of 0.662 pg L-1 and quantification limit of 2.20 pg L-1. The calibration sensitivity was of 1.22 L pg-1 for the new methodology with a linear range of 2.20 pg L-1 to 779 pg L-1 Zn(II). The tolerance levels of potential interfering ions were studied with good results. Recuperation studies were carried out by standard addition method applied to natural water samples (San Juan, Argentine) without previous treatment. The reproducibility (between-days precision) was also evaluated over 3 days by performing five determinations each day. CV% was 0.37. The performing obtained in sensitivity and selectivity thanks to chemofiltration step, converts the proposed methodology in an adequate alternative to conventional techniques for Zn(II) traces determination.