Direct analysis of honey for the total content of Zn and its fractionation forms by means of flame atomic absorption spectrometry with solid phase extraction and ultrafiltration approaches

A method of direct analysis of honey by air-acetylene flame atomic absorption spectrometry for reliable determining of the total content of Zn was evaluated and compared with measurements completed after open vessel wet oxidative digestion of honeys with a mixture of HNO3 and H2O2 Applying the proposed method the concentration of Zn in 13 raw light to dark colour honeys was found to be within 0 262 61 mu g g(-1) Additionally solutions of selected honeys were subjected to functional speciation analysis using a two-column solid phase extraction with a non ionic apolar adsorbing resin Amberlite XAD-16 and a strongly acidic cation exchanger Dowex 50W-x8-200 Another set of solutions was subjected to physical fractionation using filtration with membranes of 045 mu m pore size and molecular weight cutoff size of 100 50 30 10 and 5 kDa Both approaches used to partitioning of Zn enabled retrieving information on the fraction of total Zn that is predominant class of species (59-89%) and regarding its positive charge and very low molecular size seems to be the most available from honey and absorbable in digestion (C) 2010 Elsevier Ltd All rights reserved