【摘要】 本文用流动注射分析技术为石墨炉原子吸收光谱法测定人血中超微量金属元素建立了一个有效的在线共沉淀分离预浓集系统。基于痕量镉与双硫腙(DTZ)在弱酸性水溶液中共沉淀。沉淀收集在一编结反应器及一微型过滤器上,用60μL甲基异丁基酮(MIBK)溶洗沉淀,然后送入石墨炉进行测定。分析速度24样/h,样品消耗为1.4mL,获得的富集倍率为11。检出限(3σ)为0.003μg/L,浓度为0.06μg,/L镉时,测定精度为2.6%(n=7),测定人体血样标准参考物(GBW09132～GBW09134)中镉,结果与标准值一致。更多还原

【Abstract】 An efficient on-line coprecipitation separation and preconcentration sysytem was developed for graphite furnace atomic absorption spectrometry using a flow injection technique. Cadmium was coprecipitated with dithizone (DTZ) in weakly acidic aqueous solution and the precipitate was collected on a knotted reactor (KR) and micro membrane filter. The precipitake was dissolved in 60 μL MIBK and transferred into the graphite furnace. An enrichment factor of 11 was obtained for 20s sampling time at a sample flow rate of 2mL/min and a sampling frequency of 24/h. Adetection limit (3σ)of 0.003μg/L Cd in the sample digest was obtained with a precision of RSD 2.6% (n=7) at the 0.06μg/L level. Results obtained for the determination of cadmium in standard reference blood samples (GBW 09132-GBW 09134)agreed well with the recommended values.更多还原