| Abstract: | Cluster analysis techniques were used to examine a set of Fourier transform infrared (FT-IR) spectra of bovine serum albumin (BSA) in the adsorbed and nonadsorbed states. The region from 1480 to 1600 cm?1, comprising the amide II band, was used. Spectra were preprocessed to compensate for linear baseline variation, and the single linkage method of cluster analysis was applied. As expected, the spectra of adsorbed and nonadsorbed BSA fell into two distinct clusters. However, no further clustering was observed among the adsorbed BSA spectra on the basis of surface type, suggesting that surface specificity of the spectral changes induced in BSA by adsorption is not detectable above experimental variation. This work illustrates the value of using cluster analysis in the FT-IR study of proteins as a complement to other data analysis methods. |
