A new method for the determination of trace lead in preserved eggs was developed using flow injection （FI） coupled with flame atomic absorption spectrometry （FAAS）. During the elution procedure, the eluent was pumped into knotted reactor （KR） by the suction of the peristaltic pump. By using this new method, the dispersion of the analyte was decreased significantly, and high absorbance peak value was achieved. Emptying procedure was added in order to ensure the precision and repeatability of each determination. An enrichment factor （EF） of 11.6 was achieve in the determination of 500 μg/L lead through sampling at a flow rate of 6.0 mL/min for 60 s, while the EF obtained using the traditional method was 3.7. The limit of detection （3σ） and determination frequency of this method were 3.91 μg/L and the 41 h-1; respectively. The precision RSD for 11 replicate determinations was 1.8%. Using 0.1%0 triethannolamine as the masking reagent, the recovery rates of lead from presel＇ved egg white and yolk were determined to be 97.0% -- 99.5%.%建立流动注射在线预富集与火焰原子吸收光谱联用测定皮蛋中痕量铅的吸力洗脱新方法。实验表明：进样流速6.0mL/min;进样时间60s,测定500μg/L的铅,浓集系数由传统方法的3.7提高到11.6;检出限（3σ）为3.91μg/L;测样频率为41h-1;相对标准偏差（n=11）为1.8%。以0.1‰的三乙醇胺为掩蔽剂,铅在皮蛋中的回收率为97.0%～99.5%。洗脱过程依靠蠕动泵的吸力可明显降低被分析物在洗脱过程中的分散,提高原子吸收信号峰值和浓集系数,增加剩余样品溶液排空步骤,保证每次实验的准确性和重复性。
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