Determination of Trace Copper in Serum by a New Catalytic Kinetic Spectrophotometric Method

✍ Scribed by Huiming Mao

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 58 KB
• Volume: 53
• Category: Article
• ISSN: 0026-265X
• DOI: 10.1006/mchj.1996.0045

✦ Synopsis

A new catalytic kinetic method based on the decolorization reaction of rhodamine B has been established for the determination of copper in serum. In the presence of copper, rhodamine B can be oxidized by hydrogen peroxide in the NH 3 -NH 4 F medium. After each serum sample was digested with strong acid, the catalytic reaction was carried out in NH 3 -NH 4 F buffer (pH9.0) at 100°C for 17 min (1.0 ml buffer, 2.0 ml rhodamine B, 1.2 ml H 2 O 2 for a 25 ml reaction mixture). Copper concentration and log A 0 /A are linearly related over the concentration range of 20-140 ng/25 ml (r ‫ס‬ 0.9999, y ‫ס‬ 0.003387x -0.05969). Repeated assay of a mixture normal serum sample gave CVs of 5.2% (n ‫ס‬ 14). The mean recoveries were 98.3%, 101.2%, and 100.2% for three different serum samples. Ca, Mg, Fe, Zn, Na, K, Cl, P, and other elements in serum did not interfere with the determination. The concentrations of copper were 75-170 g/100ml in serum of 30 normal volunteers; the mean concentration was 115.4 g/100ml.