Application of rapid cloud point extraction method for trace cobalt analysis coupled with spectrophotometric determination

In this work, the analytical performance of conventional spectrophotometer was improved through the coupling of effective preconcentration method with spectrophotometric determination. Rapidly synergistic cloud point extraction (RS-CPE) was used to pre-concentrate ultra trace cobalt and firstly coupled with spectrophotometric determination. The developed coupling was simple, rapid and efficient. The factors influencing RS-CPE and spectrophotometer were optimized. Under the optimal conditions, the limit of detection (LOD) was 0.6 mu g L-1, with sensitivity enhancement factor of 23. The relative standard deviation (RSD) for seven replicate measurements of 50 mu g L-1 of cobalt was 43%. The recoveries for the spiked samples were in the acceptable range of 93.8-105%. (C) 2013 Elsevier B.V. All rights reserved.