PHYSICAL MODIFICATION OF PALLADIUM AND SILVER NANOPARTICLES LOADED ON ACTIVATED CARBON WITH 2-(2-NITROBENZYLIDENEAMINO)THIOPHENOL TO PRECONCENTRATE AND SEPARATE METAL IONS FROM FOOD SAMPLES

摘要

Preconcentration; 2-(2-nitrobenzylidene amino) thiophenol, silver nanoparticles loaded on activated carbon (Ag-NP-AC); palladium nanoparticles loaded on activated carbon (PdNP-AC); solid phase extraction%Palladium and silver nanoparticles loaded on activated carbon modified by 2-(2- nitrobenzylidene amino) thiophe-nol were applied for the enrichment of trace amount of some metal ions and their subsequent determination by flame atomic absorption spectrometry (FAAS). The influences of the analytical parameters including pH, amount of ligand and solid phase, sample flow-rate, type and conditions of eluting solution and sample volume on the metal ion recoveries were investigated. The high sorption-preconcen-tration capacity and recoveries of metal ions under study, even in the presence of various interfering ions, indicate reasonable method selectivity. The relative standard deviation and recoveries of target elements were found to be <3.0 and >94%, respectively. The optimum values were set at-pH 5, amount of nanoparticles 0.08 g, eluent flow rate 1.5 ml min~(-1), condition of eluent 5.0 ml of 4.0 M HNO_3, and sample volume 1400 ml. The method was applied to determine analyte ions in real samples.