Flow-Injection Chemiluminescence Determination of Cobalt Using a Cobalt(II) (1,10-Phenanthroline)3 Complex-Catalyzed Lucigenin-Periodate Reaction

A flow injection chemiluminescence method is proposed for the determination of cobalt, based on the strong catalytic effect of Cobalt(II) (1,10-phenanthroline)3 complex on the lucigenin-periodate reaction in alkaline medium. Under the optimum experimental conditions, the chemiluminescence signal responded linearly to the concentration of cobalt(II) in the 1.0 × 10−9–3.0 × 10−7 g mL−1 range with a detection limit of 4.4 × 10−10 g mL−1 cobalt(II). The relative standard deviation for the determination of 5.0 × 10−8 g mL−1 of cobalt was 2.3% in eleven replicated measurements. The method was successfully applied to the determination of cobalt(II) in pharmaceutical preparations.