离子色谱-电感耦合等离子体质谱法测定饮用水中痕量无机锑(III)

Detection of trace inorganic antimony (III) in water by ion chromatography-inductively coupled plasma mass spectrometry

中文关键词:  离子色谱-电感耦合等离子体质谱法  饮用水  三价无机锑

英文关键词:ion chromatography-inductively coupled plasma mass spectrometry  drinking water  inorganic antimony (III)

中文摘要:

      目的 建立使用固相萃取(solid phase extraction, SPE)富集、在线氧化洗脱预处理, 离子色谱-电感耦合等离子体质谱联用(ion chromatography-inductively coupled plasma mass spectrometry, IC-ICP-MS)测定饮用水中痕量三价无机锑(iSb(III))的方法。方法 水样中痕量iSb(III)经过弱阳离子交换SPE柱富集后, 依次使用甲醇、水净化, 后使用1% H2O2+1%氨水混合溶液洗脱, 洗脱液中iSb(III)可全部转化为iSb(V), IC-ICP-MS测定iSb(V)浓度间接测得饮用水样中痕量iSb(III)。水样中iSb(V)不能被弱阳离子SPE富集, 因此不干扰测定。结果 富集倍率为10, 方法在0.010~0.200 μg/L范围内具有良好线性, 相关系数r为0.996~0.998, 检出限0.003~0.004 μg/L, 加标回收率94%~102%, 日内相对标准偏差(RSD)1.7%~5.3%, 日间精密度为0.6%。结论 本方法稳定可靠, 极低的检出限可用于饮用水中痕量甚至超痕量iSb(III)的检测。

英文摘要:

      Objective To establish a method for the determination of trace trivalent inorganic cerium [iSb(III)] in drinking water by solid phase extraction enrichment (SPE), online oxidation elution pretreatment, and ion chromatography-inductively coupled plasma mass spectrometry (IC-ICP-MS). Methods Trace iSb(III) was first enriched by a weak cationic exchange solid phase extraction (SPE) column, then purified by methanol and pure water. Finally, the enriched SPE column was eluted with 1% H2O2+1% NH3. The iSb(III) in the eluent could be converted into iSb(V) completely. Since the iSb(V) could be easily detected by ion chromatography-inductively coupled plasma mass spectrometry (IC-ICP-MS) with shorter retention time and better peak shape, the iSb(III) in water was measured indirectly. The iSb(V) could not retain in a weak cationic exchange SPE column, so it brought no interfere with the method. Results When the enrichment factor was 10, the method had a satisfactory linearity with the curve ranging from 0.010 to 0.200 μg/L, and the linear coefficient r was 0.996?0.998. The LOD was of 0.003?0.004 μg/L, and the recoveries were of 94%?102% with intra-day RSD of 1.7%?5.3% and inter-day RSD of 0.6%. Conclusion This method is stable and reliable, and the detection limit can be used for the detection of trace or even trace amounts of iSb(III) in drinking water.