| AVS 58th Annual International Symposium and Exhibition | |
| Biomaterial Interfaces Division | Thursday Sessions |
| Session BI-ThP |
| Session: | Biomaterial Interfaces Poster Session |
| Presenter: | Kenan Fears, Naval Research Laboratory |
| Authors: | K.P. Fears, Naval Research Laboratory D.E. Day, Missouri University of Science and Technology D.Y. Petrovykh, International Iberian Nanotechnology Laboratory T.D. Clark, Naval Research Laboratory |
| Correspondent: | Click to Email |
Bovine serum albumin (BSA) is a widely studied globular protein that contains ca. 68% of alpha-helices and <2% of beta-sheets in its native conformation. The well characterized secondary structure of BSA is commonly used as a benchmark for electronic (ECD) and vibrational (VCD) studies of proteins in solution. Both ECD and VCD indicated a substantial loss of helical structure accompanied by an increase of beta-sheet character in BSA thermally denatured in solution. In surface adsorption experiments, hydroxyapatite microspheres were incubated in solutions with low (1.0 mg/mL) or high (50.0 mg/mL) concentrations of BSA for one hour, then triple rinsed and re-suspended in buffer for analysis. The ECD spectra were similar for BSA adsorbed from low and high concentration solutions, both showing a sizeable increase in beta-sheet character upon adsorption, while being dominated by alpha-helical features. The VCD spectra also exhibited stronger peaks in the beta-sheet region upon adsorption of BSA on hydroxyapatite. VCD signal enhancement, however, was observed upon adsorption from the high concentration BSA solution, indicating the formation of macroscopic chiral structures. The analysis of proteins adsorbed on surfaces thus can be enhanced by taking advantage of the complementary sensitivities of ECD and VCD spectroscopies to the secondary structures of biomolecules.