DIFFUSION OF BOVINE SERUM-ALBUMIN IN AMYLOPECTIN GELS MEASURED USING FOURIER-TRANSFORM INFRARED MICROSPECTROSCOPY

A new method of characterizing diffusion in gels using Fourier transform infrared microspectroscopy is described. The system studied was bovine serum albumin (BSA) diffusing into amylopectin gels. By following the height of the amide peak of the BSA as a function of position along the sample, it is possible to build up the concentration profile. From this, the diffusion coefficient can be determined as a function of BSA concentration, amylopectin concentration, and added salt concentration. It is shown that charge effects are very important in this system. The dependence of the diffusion coefficient on the amylopectin concentration can be well fitted by a stretched exponential.