A new and versatile procedure for the spectrophotometric determination of manganese using micelle-mediated extraction was developed. The method involved the formation of an ion association complex between manganese oxyanion (MnO4-) and brilliant green in acidic solution and the complex was extracted into the surfactant Triton X-100 at optimum conditions. The surfactant-rich phase which contains manganese complex was mediated with solvent and the Mn content measured spectrophotometerically at absorption maximum (λmax = 657 nm). The effects of the several variables which impact the CPE efficiency were optimized by one-factor-at-a-time (OFAT). Under the optimized conditions, enrichment factor of 282 was achieved leading to limit of detection and limit of quantitation of 0.086 and 0.242 μg μL-1 respectively, with linearity of 0.2-3 μg mL-1. The precision (RSD%) of the proposed method was of 1.07% . The interferences effect of such ions was also studied. This method is applicable in the determination of manganese in environmental and vital samples.
Manganese oxyanion, Brilliant green, Cloud-point extraction, Spectrophotometry