Spectrophotometric Determination of Cobalt(II) and Cyanocobalamin with Vanillilfluprpme and Its Applications

Spectrophotometric determination of cobalt(II) was accomplished with vanillilfluorone (VF) in the presence of dimethylbenzyltetradecylammonium chloride (Zephiramine, Zep). In the determination of cobalt(II), Beer's law was obeyed in the range of 24-470 ng/ml, with an effective molar absorption coefficient (at 575 nm) and relative standard deviation of 1.35×10 5lmol -1 cm -1 and 0.66% (n=5), respectively. The composition ratio of the colored complex was determined by the mole ratio and continuous variation methods, and it was found to be Co(II) : VF : Zep =1 : 2 : 4. Analysis of cyanocobalamin by the same procedure showed that cyanocobalamin could be determined in the concentration range of 0.5-0.11μg/ml using the proposed method. Cobalt, having a Clarke number of 4×10 -3, is produced along with nickel, and a small amount of cobalt is also contained in copper zinc ore. Cobalt is present in steel as an impurity and is used as an additive in alloy steel in the refinery process. Additionally, cobalt is one of the essential trace elements.