HPLC-ICP-MS或HPLC-FAAS法分离测定硒化合物（英文）

 提出了一种用高效液相色谱（HPLC）分离和用电感偶合等离子体质谱仪（ICP－MS）或火焰原子吸收光谱仪（FAAS）作元素专一检测器在线测定硒的化学形态的方法。在优化的HPLC条件下，用ESAⅢ阴离子色谱柱（250mm×4．6mm），以柠檬酸铵为流动相（5．5mmol／L，pH5．5，流速1．5mL／min），进样量100μL，分离和测定三甲基硒离子、硒代蛋氨酸、亚硒酸和硒酸盐只需8min。HPLC－FAAS在线分析4种硒化合物的检测限为p（Se）=1mg／L。

Determination of selenium compounds by HPLC with ICP-MS or FAAS as selenium-specific detector.

A speciation method was developed for selenious acid, selenic acid, trimethylselenonium ion (TMSe) and selenomethionine (SeMet). Separation of the four selenium species was achieved by HPLC on an ESA Anion III anion-exchange column using aqueous mobile phase of 5.5 mmol/L ammonium citrate at pH 5.5 with a flow rate of 1.5 mL/min. Under the optimal conditions, the four selenium species were separated within 8 minutes. On-line selenium-specific detection was carried out with an inductively coupled plasma mass spectrometer (ICP-MS) or a flame atomic absorption spectrometer (FAAS). The detection limits of HPLC-FAAS were approximately rho(Se) = 1 mg/L for each compound (100 microL injection). To increase the nebulization efficiency of the ICP-MS, the Meinhard concentric nebulizer was replaced by an ultrasonic nebulizer (USN). The ICP-MS signal intensity was increased by a factor of 7 for selenious acid and 24 to 31 for TMSe, SeMet and selenic acid with the USN compared to that with the Meinhard nebulizer. The detection limits of the HPLC-USN-ICP-MS were rho(Se) = 0.08 microgram/L for TMSe, rho(Se) = 0.34 microgram/L for selenious acid, rho(Se) = 0.18 microgram/L for SeMet and rho(Se) = 0.07 microgram/L for selenic acid.