MICROWAVE-OVEN DIGESTION PROCEDURE FOR ATOMIC-ABSORPTION SPECTROMETRY ANALYSIS OF BONE AND TEETH

The purpose of this study was to develop a new method for determination of the mineral element in teeth and bone using a microwave digestion procedure coupled to atomic absorption spectrometry. Samples were ashed at 450 degrees C for 4.5 h and subsequently digested in a microwave oven at maximum power (600 W) for 10 s using a Teflon closed Parr bomb. This method permits the rapid dissolution of the biological samples, avoiding operations such as slicing and cutting which often introduce alterations in sample homogeneity and may contribute to their contamination. The analysis of Na, K, Ca, Mg, Fe, Zn, Ba, Cd and Pb showed good reproducibility, precision and accuracy as compared with the certified values fdr the IAEA H-5 animal bone. Average concentration for those elements in permanent teeth obtained from children aged 11-18 years by orthodontics are given.