Probe Studies of the Gelation of Gelatin using the Forced Rayleigh Scattering Technique

Publisher Summary This chapter focuses on the probe studies of the gelation of gelatin using the Forced Rayleigh Scattering Technique (FRS). It presents a historical background as well as the principle of the FRS technique. The technique measures the diffusion of the chromophoric groups and can be used, therefore, to measure the diffusion of one species in a complicated mixture. In the study described in the chapter, the diffusion of a dye-labeled protein molecule, Bovine Serum Albumin (BSA), has been measured in an aqueous buffer solution and in an aqueous solution of gelatin. The study has been able to probe the development of structure in the gelling mixture through changes in the diffusional characteristics of the BSA revealed by FRS. Aqueous solutions of BSA are completely miscible with gelatin solutions at 40-50 °C without any apparent aggregation of the BSA. It is, therefore, possible to mix dye-labeled BSA with gelatin solutions and carry out FRS measurements on the BSA in the gelatin + BSA mixture. The chapter reports a FRS study of the self-diffusion of dye-labeled BSA in gelatin during the process of gelation.