Combination of solid phase extraction based on nano alumina and liquid-liquid extraction for selective determination of palladium in food samples

A new simple and reliable method for rapid and selective extraction and determination of trace Pd(II) was developed. Combination of solid phase extraction (SPE) and liquid-liquid extraction (LLE) of trace amounts of palladium in food and water samples has been done successfully. By coupling of SPE with LLE, advantages of both can be combined including high extraction recovery and preconcentration factor (PF), environmental friendliness, low cost and appropriate time of analysis. All conditions for SPE and LLE were optimized in order to reach high PF and extraction recovery. The metal ion was eluted completely with 1.5 mL 2 M HClO4 in acetylacetone and measured by flame atomic absorption spectrometry (FAAS). The optimum experimental conditions such as pH, sample volume, amount of sorbent and concentration of eluent on the sorption of Pd(II) were evaluated. Under the optimized conditions, the sorption capacity of the modified nano-gamma-alumina for Pd(II) was 13.5 mg/g. Preconcentration from 200 mL sample solution permitted a preconcentration factor of 266. The limit of detection of this method for Pd(II) was 0.2 mu g/L and the relative standard deviation (RSD) of 100 ng/mL of Pd(II) was 2.3% (n = 10).