Robert M. Rosenberg

DYE-BINDING METHODS

Publisher Summary This chapter discusses dye-binding methods. The earliest evidence for the interaction of dyes with proteins was the observation of indicator errors in protein solutions. It has also long been known that acidic and basic dyes are effective protein precipitants. The chapter mainly focuses on the information about proteins which can be obtained from dye-binding methods and the analytical procedures which have been based on them. The highly specific interactions of dye happens with antibodies and the extensive studies of dye binding by insoluble proteins such as wool will be mentioned only incidentally. The experimental methods which will be discussed in detail are those which have been most widely used and have the most general application. Any treatment of dye binding by proteins must take into account the fact that it is possible for more than one dye molecule to be bound by a protein molecule. If the dye molecules are charged, successive dye molecules are less strongly bound because of the electrostatic repulsion of ions already on the protein. The situation can be treated in terms of an electrostatic term in the free energy of binding or by multiplying the intrinsic constant by an exponential factor.