高效液相色谱-喷壁/薄层安培检测器用于同时测定5种环境优先污染酚

Simultaneous HPLC Analysis of Five Environment Priority Pollutants of Phenols with a Wall-jet / thin-layer Amperometric Detector

结合传统的喷壁式和薄层式安培检测器,制备了一种新型的喷壁/薄层安培检测器。联合高效液相色谱(HPLC)同时对5种环境优先污染酚进行了检测。实验发现,安培检测工作电极面积的增大会导致响应电流的增大,但同时也会增大噪声,因此,基于信噪比优化电极面积是重要的。选用色谱柱SHIM-PACK VP-ODS(150 mm×4.6 mm),流动相V(甲醇)∶V(0.1 mol/L PBS,pH=7.5)=40∶60,柱温40℃,流速1 mL/min,进样量20μL,安培检测电位为1.0 V,紫外检测波长为220 nm,喷壁-薄层安培检测器不经富集对对硝基酚、苯酚、间甲酚、2,4-二氯苯酚和2,4,6-三氯苯酚共5种酚类物质的检测下限均低于1μg/L(S/N=3),优于相同条件下的紫外检测器和商品电化学检测器。用于实际水样分析亦获满意结果。

A self-fabricated wall-jet/thin-layer electrochemical detector（ECD） was developed by combining the classical wall-jet and thin-layer ECD, which is coupled to high-performance liquid chromatography for simultaneous determination of five priority pollutants of phenols. The results show that both the response current and the noise increase with the increase of electrode area, thus an appropriate electrode area is important for obtaining a good analytical performance at enhanced signal-to-noise ratio （S/N）. By using SHIM-PACK VP-ODS（ 150 mm x4. 6 mm） column, mobile phase of a mixture of methanol and 0. 1 mol/L PBS（pH =7. 5）（volume ratio is 40：60）, oven temperature： 40 ~C, flow rate：l mL/min, injection volume： 20 txL, detection potential： 1.0 V, detection wavelength： 220 nm, the limits of detection without preconcentration are all lower than 1.0 ~xg/L （ S/N = 3 ） for p-nitrophenol, phenol, m-cresol, 2, 4- dichlorophenol and 2,4,6-triehlorophenol, which are lower than those obtained with a UV detector and a commercial electrochemical detector. The method has results. been tested using river water samples with satisfactory