石墨炉与火焰原子吸收光谱法测定洗发液中铅的比较

Comparative study on methods of GF- AAS and flame AAS determination of lead in shampoo

目的建立石墨炉原子吸收光谱法测定洗发液中铅的方法。方法分别按火焰原子吸收光谱法、石墨炉原子吸收标准曲线法、石墨炉原子吸收标准加入法对CNAS T0652洗发液样品进行比较测定,并与CNAS T0652能力验证的结果进行对比。结果石墨炉原子吸收标准曲线法测定结果偏低。石墨炉原子吸收标准加入法测定铅含量的结果与本实验室火焰法测定结果、CNAS T0652能力验证结果中位值差异无统计学意义。平均加标回收率为101.5%,RSD为1.51%,最低检出限为0.012 mg/kg,比火焰原子吸收法低200倍。结论石墨炉原子吸收标准加入法消除了基体干扰,方法简便、准确、灵敏,尤其适用于含低浓度铅样品的测定。

Objective To establish a method for determination of lead in shampoo by graphite furnace atomic absorption spectrometry. Methods The lead in CNAS T0652 shampoo sample was determined by flame AAS, GF - AAS and GF - AAS stand- ard addition method respectively, then the determination results were compared with CNAS T0652 performance validation resuits. Results GFAAS showed relatively low lead level. While GF - AAS standard addition method performed no obvious difference with flame AAS and the median of the CNAS T0652 in lead level test results. The recovery of GF - AAS standard addition method was 101.5% , the RSD was 1.51%, the lowest detection limit was O. 012 mg/kg, 200 times lower than that of flame AAS. Conclusion The GF - AAS standard addition method can eliminate matrix interference, and it is simple, accurate and sensitive, especially suitable for determination of samples with low lead content.