Direct determination of phosphorus in different food samples by means of solid sampling electrothermal atomic absorption spectrometry using Pd plus Ca chemical modifier

In this study, direct determination of phosphorus in different food samples (milk powder, banana, and dried banana) and in various standard reference materials (apple leaves, bovine liver, pine needles) using solid sampling electrothermal atomic absorption spectrometry was investigated. Aqueous standards were used for all determinations. 5 mu g Pd+5 mu g Ca modifier mixture was used in all experiments. Pyrolysis temperature and atomiation temperature were 1100 degrees C and 2500 degrees C, respectively. High background was reduced by applying a cool-down step in the furnace program. The accuracy of solid sampling results was checked by determination of the phosphorus content after dissolving samples. There was no significant error between results found by solid sampling and solution techniques. In addition solid certified materials were investigated. There were no significant differences between the phosphorus content of CRM and results obtained. The limit of detection, based on three times the standard deviation was 0.018 mu g P. (c) 2005 Elsevier B.V. All rights reserved.