Spectrophotometric Determination of Cobalt(II) Using the Chromogenic Reagent 4,4′-Diazobenzenediazoaminoazobenzene in a Micellar Surfactant Medium

作者：Gu Jin, Yurui Zhu, Wanquan Jiang, Boping Xie, Bin Cheng · 发表于：The Analyst · 年份：1997 · DOI：10.1039/a606804i · 被引用次数：33 · 研究领域：Molecular Sensors and Ion Detection、Electrochemical sensors and biosensors、Analytical Chemistry and Sensors

A highly sensitive spectrophotometric method for the determination of cobalt(II) using the chromogenic reagent 4,4′-diazobenzenediazoaaminoazobenzene (BBDAB) was developed. The optimum conditions for the chromogenic reaction of cobalt(II) with BBDAB were studied in the presence of Triton X-100 and sodium tetraborate. The calibration graphs were rectilinear in the range 0–7 µg per 25 cm 3 cobalt(II). The apparent molar absorptivity is 1.72 × 10 5 dm 3 mol - 1 cm - 1 with a Sandell’s sensitivity of 0.00035 µg cm - 2 . The method was applied to the determination of cobalt in soil and vitamin B 12 with satisfactory results.