Determination of Cobalt in Some Plants by Reversed-Phase High Performance Liquid Chromatography

摘要

The separation and determination of cobalt chelate with 4-(2-pyridylazo)resorcinol (PAR) by reversed-phase HPLC was investigated.The Co(III)-PAR chelate was separated on a C_(18) siloxane bonded phase and eluted within 5.4 min with methanol-water-acetonitrile (1 x 10~(-2) mol L~(-1)) and sodium acetate (55:40:2.5:2.5 v/v) containing 5 x 10~(-3) mol L~(-1) ethylenedi-aminetatraacetic acid (EDTA) (pH 7.5).The detection limits of Co(III) at 520 nm are 1.2 mu g L~(-1).The method was applied to the determination of cobalt in some samples of plants.The contents of cobalt in the plants samples were found in the ranges,0.941-0.141 mg/kg (dry matter).Rosa canina is rather rich in cobalt and is recommended as a source.