DETERMINATION OF TRACE AMOUNTS OF COBALT AT SUB-MU-G 1(-1) LEVEL BY SOLID-PHASE SPECTROPHOTOMETRY

A very sensitive method for the determination of trace amounts of cobalt has been developed, based on Solid-Phase Spectrophotometry (SPS). The method is based on the fixation of cobalt(II) as the 4-(2-pyridilazo)resorcinol complex on an anion-exchange resin. Resin phase absorbance is measured directly, and it allows the determination of cobalt (with a RSD of 2.4 %; in the range of 0.4 -3.8 μg 1-1. The method was applied to the determination of cobalt (II) in different samples, namely beers, drugs and waters. © 1992, Taylor & Francis Group, LLC. All rights reserved.