Investigation of Cu(II) Binding to Bovine Serum Albumin by Potentiometry with an Ion Selective Electrode: A Biophysical Chemistry Experiment for the Undergraduate Curriculum

Abstract

The binding of ligands to biological macromolecules should be included in the laboratory of the undergraduate biophysical chemistry curriculum. An interesting experiment investigating Cu(II) ion binding to bovine serum albumin (BSA) by using potentiometry with the ion selective electrode is described and offers attractive features over some traditional methodologies. Students analyze experimental data to obtain the average number of Cu(II) binding sites on a BSA molecule and the values of corresponding binding constants, either by a specifically designed computer program for regression to the binding equation, or by a graphic method in terms of Scatchard model.