【摘要】 建立衍生化-溶剂提取-气质联用(GC-MS)测定水中痕量烷基汞的分析方法。用巯基固相萃取柱富集水中的烷基汞,4 mol/L盐酸洗脱,在HAc-NaAc缓冲体系(pH 4～5)下与50μL四丙基硼化钠(1%THF)衍生反应,0.5 mL正己烷提取烷基汞的衍生物,采用气相色谱-质谱联用选择离子方式(SIM)进行检测,以4-溴氟苯为内标定量,在2～200 ng/L范围内线性良好,1 L水样中甲基汞和乙基汞的检出限可达1 ng/L以下。实际样品添加回收率在69.7%～80.9%之间,准确度好;平行5次进行精密度试验,相对标准差在8.5%～10.3%之间。结果表明:方法稳定性好、操作方法实用,可用于水中痕量烷基汞的测定。更多还原

【Abstract】 A sensitive and repeatable method was developed and applied to determine alkyl mercury in water by derivatization-solvent extraction-gas chromatography-mass spectrometry(GC-MS). The water samples were extracted by SH solid-phase extraction column. The SPE column was eluted by 4 mol/L HCl and the acidic solution was adjusted to neutral. Then HAC-NaAC buffer(pH 4-5) and 50 μL sodium tetrapropylborate(NaBPr4) solution(1% THF)were added to the solution. The derivatives can be completely extracted by 0.5 mL n-hexane. The analytes were determined by GC-MS in SIM mode and quantified by internal standard method.The results showed that the alkyl mercury derivatives had a good linear relationship in the rang 2 ng/L to 200 ng/L. The limits of detection were less than 1 ng/L in about 1 L water samples. The recoveries of the analytes in real water samples spiked with standards were all in the range of 69.7% to 80.9%. Th erelative standard deviations(RSD) were between 8.5% to 10.3 %(n=5). The results show that the method is sensitive and accurate for the determination of the alkyl mercury in water samples.更多还原