Shedding Light on the Conformation of Proteins and Other Macromolecules at an Interface

Abstract

An attractive way to probe interfacial phenomena is through the utilization of total internal reflection-based spectroscopic methods, in which the evanescent field is used to photo-excite an absorbing species situated within the penetrating field. In this paper we discuss both absorbance and time-resolved fluorescence evanescent wave techniques that we have developed. We highlight how these techniques can be utilized successfully for interrogating the adsorption behaviour of proteins and polymers as a function of distance from a solid/solution interface into bulk solution. Information provided by these methods regarding how protein and polymer molecular conformation is affected by their adsorption/interaction at a surface is discussed with specific reference to poly(2-vinylpyridine), hen egg white lysozyme, and bovine serum albumin.