Improvement and Discussion of the Bicinchoninic Acid Method for Copper Determination in Bacterial Leachates and Acid Mine Drainage

−− The spectrophotometric method for the determination of cuprous ions in solution presented by Anwar et al. (2000), has since been analyzed and improved, especially with regard to interference from iron and ion species commonly found in acid mine drainage (AMD). The reduction of cupric ions in the presence of ferrous ions, not considered by Anwar et al., renders this method unfeasible for cuprous ion determination. In the absence ferrous ions, the method is simple, fast, economic, accurate and very reliable for total copper determination, even for copper concentrations as low as 5 mg/L. Iron concentrations > 5 g/L produce less than 3% error in determination of copper concentrations of 50 mg/L. Typical AMD ion concentrations do not interfere, except for aluminum which interferes significantly at ten times (x10) AMD concentration