Preconcentration of Zinc and Manganese using 1-(2-pyridylazo)-2-naphthol Anchored SiO2 Nanoparticles

Abstract

A new analytical method using 1-(2-pyridylazo)-2-naphthol modified SiO2 nanoparticles as solidphase extractant has been developed for the preconcentration of trace amounts of Zn(II) and Mn(II) in
water and food samples. Conditions of the analysis such as preconcentration factor, effect of pH,
sample volumes, shaking time, elution conditions and effects of interfering ions for the recovery of
analyte were investigated. At optimum pH the adsorption capacity of nanometer SiO2-PAN was found
to be 71.50 and 24.22 µmol g-1 and the detection limit (3σ) was found to be 0.90 and 0.42 µg L-1 for
Zn(II) and Mn(II) respectively. The extractant showed rapid kinetic sorption. The adsorption
equilibrium of Zn(II) and Mn(II) on nanometer SiO2-PAN was achieved just within 15min. Adsorbed
Zn(II) and Mn(II) were easily eluted with 6 mL of 6 mol L-1 hydrochloric acid. A preconcentration
factor was 50 in both the metal ions. The method was applied for the determination of trace amounts of
Zn(II) and Mn(II) in various water and food samples.