Binding of lead ion to bovine serum albumin studied by ion selective electrode.

The binding of Pb2+ to bovine serum albumin (BSA) at neutral pH was studied using lead ion selective electrode. The binding data was treated according to Scatchard Equation. The number of binding classes and the number of binding sites, intrinsic dissociation constants and stepwise binding constants for each class were determined. Two binding classes were found. Four binding sites in the first class and five binding sites in the second class were determined. Binding in the first class was stronger than in the second. Similar binding studies were carried out with heat treated BSA. It was found that not only the number of binding sites but also the strength of binding increases upon heat treatment.