Optimization of Experimental Conditions for Determination of Lead in Vegetables by Graphite Furnace Atomic Absorption Spectrometry
Objective:To establish and optimize a graphite furnace atomic absorption spectrometry method for the determination of lead in vegetables.Method:Optimize the amount of matrix modifier added,instrument ashing temperature,and atomization temperature,and conduct methodological validation experiments.Result:The optimal detection conditions were as follows:5%palladium nitrate solution was selected as the matrix modifier,with a dosage of 5 μL,ashing temperature of 800℃,and atomization temperature of 1 800℃.When the lead content is between 0 μg·L-1 to 40.0 μg·L-1,the standard curve equation is y=0.004 79x+0.004 87,and the correlation coefficient R2 is 0.999 7,indicating a good linear relationship.The detection limit of the method is 0.5 μg·L-1,and the lower limit of determination is 0.01 mg·kg-1.The spiked recovery rates of the three levels in celery samples ranged from 95.00%to 98.33%,with a relative standard deviation of 1.73%to 8.67%.Conclusion:The method established in this study has high precision and accuracy,and is suitable for rapid and accurate detection of lead content in vegetables.