Research of ascorbic acid prereduced palladium as the matrix modifier used for determination of lead in shellfish

Under the condition of using the ascorbic acid prereduced palladium as the matrix modifier, ashing temperature and atomization temperature were found and a graphite furnace atomic absorption spectrometry was developed for determination of lead in shellfish.The experimental results demonstrated that the standard curves of lead concentrations and absorbance were liner in the range of 0～50.0μg/L lead,the correlation coefficient was 0.9 997 under conditions of using the ascorbic acid prereduced palladium as matrix modifier at the ashing temperature of 800℃and atomization temperature of 1900℃.When the sample weight was 0.250g,and constant volume was 25mL,the limit of detection were 0.04mg/kg,the recoveries were between 93.5～103.0%,RSD was between 1.41%～4.35%.The results of analyzing standard material of sinonovacula constricta were in the range of permissible error of measured value. The method was better than the other methods of high sensitivity, accuracy and reliablility,was suitable for the detection of lead in shellfish,and was used to the determination of lead in shellfish of the North and Central Fujian.The results showed that the shellfish of the North and Central Fujian were qualified.