气相色谱和原子荧光联用测定生物和沉积物样品中甲基汞

提出了一种气相色谱和原子荧光在线联用测定甲基汞的方法。对气相色谱和原子荧光的在线联用进行了设计，优化了进样口温度、载气流速、尾吹气流量及氩气流量等实验条件。在最佳仪器条件下，甲基汞(MMC)和乙基汞(EMC)的绝对检出限(3σ)可达0.005 ng。对于10 ng·mL-1 MMC和EMC标准溶液，连续5次进样测得精密度(RSD)分别为2.5％和1.3％。对标准参考物(DORM-2)的分析结果与标准值一致。两个沉积物中甲基汞的加标回收率分别为70％和77％。方法准确、灵敏，可应用于生物和沉积物样品中甲基汞的分析。

Determination of Methylmercury in Biological and Sediment Samples by Capillary Gas Chromatography On-Line Coupled with Atomic Fluorescence Spectrometry

A comprehensive method for the determination of methylmercury by capillary gas chromatography (GC) on-line coupled with atomic fluorescence spectrometry (AFS) was developed. The hyphenation system was carefully designed and the operation conditions such as injector temperature, carrier gas flow rate, make-up gas flow rate and argon flow rate were optimized in detail. The absolute detection limits (3sigma) were 0.005 ng of Hg for both methylmercury (MMC) and ethylmercury (EMC). The relative standard deviations (RSD, n = 5) for MMC and EMC at 10 ng x mL(-1) of Hg levels were 2.5% and 1.3%, respectively. The method was evaluated by analyzing a certified reference material (DORM-2), and the MMC concentration determined was in good agreement with the certified value. In addition, the recoveries of MMC in two sediment samples were 70% and 77%, respectively. The proposed method was accurate, sensitive and suitable for the determination of MMC in biological and sediment samples.