高效液相色谱-在线消解-氢化物发生原子吸收光谱联用技术研究

High Performance Liquid Chromatography Combined with Atomic Absorption Spectrometry Using Ultraviolet Digestion-Hydride Generation Interface

运用自行设计的接口,实现了高效液相色谱与原子吸收光谱的联用。通过对常见砷化合物进行形态分析,考察了自行设计的高效液相色谱-紫外在线消解-氢化物发生原子吸收光谱联用(HPLC-UV-HGAAS)接口的性能。实现了将分离后不能直接用于氢化物发生的大分子,通过紫外“在线”消解成小分子砷化合物的目的。确定了仪器的最优化分析条件。建立了快速、直接、连续、在线的HPLC-UV-HGAAS元素形态分析方法。

The coupling of high performance liquid chromatography （HPLC） with atomic absorption spectrometry （AAS） was achieved by using a simple laboratory-built ultraviolet （UV）-hydride generation （HG） interface. Compared with the former techinque, a 0.4 m quartz tube was used for UV digestion instead of the 5 m teflon coil without decreasing the UV digestion efficiency of the organic arsenic compounds. As a nesult, the volume of the interface was greatly minished, so the miniaturization and integration of the instrument was achieved . The coupling instrument was used to separate four arsenic species （ arsenite , arsenate , methylar - sonic acid, dimethylarsinic acid ） that are of toxic importance. The optimized analysis conditions were obtained. The results showed good repeatability （ RSD 〉 6.56% ）, good linearity （ r 〉 0. 997 ） and low detection （ detection limit 〉 14.4 mg/L）. Then the performance for on-line digestion of organic arsenic species including arsenobetaine （AsB） and arsenocholine （AsC） was investigated. A rapid, direct, continuous, online HPLC-UV-HGAAS hyphenated technique was developed.