塞曼火焰原子吸收与石墨炉原子吸收法测定明胶空心胶囊壳中铬的方法比较

目的:研究塞曼效应背景校正的火焰和石墨炉原子吸收法测定胶囊中铬的影响。方法:采用微波消解仪对胶囊壳样品进行消解,在波长359.3 nm下,灯电流7.5 mA;狭缝宽1.3 nm,塞曼背景校正,分别采用塞曼火焰原子吸收和石墨炉原子吸收法进行测定。结果:火焰原子吸收法:线性范围0.04～1.0 mg.mL-1;相关系数为0.9998,检测限5.26 ng.mL-1,RSD为0.68%～1.0%,加样回收率为100.0%～116.7%;石墨炉原子吸收法:线性范围为1～20 ng.mL-1,相关系数为0.9998,检测限为0.26 ng.mL-1,RSD为1.7%～4.9%,加样回收率为98.2%～105.6%。结论:塞曼火焰原子吸收法简便、快捷,能满足大量样品筛选及企业内部质控筛选与定值;石墨炉原子吸收法检测限较前者低,准确度较高。

Comparison of chromium determination in capsule shells by Zeeman flame and graphite furnace atomic absorption spectrophotometry

Objective:To investigate effects of Zeeman flame atomic absorption spectrophotometry(AAS) and graphite furnace AAS on the determination of chromium in capsule shells.Methods:Microwave digestion was adopted to digest the capsule shells.Zeeman effect was used in the background correction.The slit width was set at 1.3 nm,lamp current 7.5 mA,and the content of chromium was determined at a wavelength of 359.3 nm by Zeeman flame AAS and graphite furnace AAS respectively.Results:For the Zeeman flame AAS method,the calibration curve was linear in the range of 0-1.0 μg·mL-1(r=0.9998),the detection limit was 5.26 ng·mL-1,RSD was 0.68%-1.0% and the average recovery was 100.0%-116.7%.For the graphite furnace AAS method,the calibration curve was linear in the range of 0-20 ng·mL-1(r=0.9999),the detection limit was 0.26 ng·mL-1,RSD was 1.7%-4.9% and the average recovery was 98.2%-105.6%.Conclusion:The Zeeman flame AAS method is simple,fast,and suitable for the preliminary determination of chromium in capsule shells in emergent cases;the graphite furnace AAS method is sensitive,accurate,and suitable for the determination of chromium in capsule shells in any case.