Sorption and Preconcentration of Zineb and Maneb using 1-(2-pyridylazo)- 2-naphthol Anchored on Silica Nanoscavengers

A new analytical method in which 1-(2-pyridylazo)-2-naphthol anchored SiO2 nanoparticles have been used as solid-phase extractant for the preconcentration of trace amounts of zineb and maneb in water and food samples. Conditions of the analysis such as preconcentration time, effect of pH, sample volumes, shaking time, elution conditions and effect of interfering ions for the recovery of analyte have been optimized. The extractant showed rapid kinetic sorption. The adsorption equilibrium of zineb and maneb on nanometer SiO2-PAN was achieved in 15 min. Adsorption capacity and detection limit (3σ) of nanometer SiO2-PAN has been found to be 42.52 and 50.80 μmol g^-1and 0.93 and 0.60μgL^-1 for zineb and maneb respectively under optimized conditions. Adsorbed zineb and maneb were easily eluted with 6 mL of 6 mol L^-1 hydrochloric acid. The method was applied for the determination of trace amounts of zineb and maneb in various food samples and spiked water samples.