摘要
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 spectro- fluorimetry (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, quantita- tive 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 selec- tivity thanks to chemofiltration step, converts the proposed methodology in an adequate alternative to con- ventional techniques for Zn (II) traces determination.
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 spectro- fluorimetry (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, quantita- tive 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 selec- tivity thanks to chemofiltration step, converts the proposed methodology in an adequate alternative to con- ventional techniques for Zn (II) traces determination.
