title: Size-dependent denaturing kinetics of bovine serum albumin adsorbed onto gold nanospheres.
abstract: We have used localized surface plasmon resonance (LSPR) to monitor the kinetics of thermal denaturing of bovine serum albumin (BSA) adsorbed onto gold nanospheres of size 5 nm-100 nm. The effect of the protein on the LSPR was monitored by visible extinction spectroscopy. The wavelength of the peak extinction (resonance) is affected by the conformation of the adsorbed protein layer, and as such can be used as a very sensitive probe of thermal denaturing that is specific to the adsorbed (as opposed to free) protein. The time dependence of the denaturing is measured in the temperature range 60 degrees C-70 degrees C, and the lifetimes are used to calculate an activation barrier for thermal denaturing. The results show that thermally activated denaturing of proteins adsorbed onto nanoparticles has a nanoparticle-size-dependent activation barrier, and this barrier increases for decreasing particle size. This may have important implications for other protein-nanoparticle interactions.
authors.affiliation: Department of Physics and Astronomy, Guelph-Waterloo Physics Institute, University of Waterloo, 200 University Ave. W., Waterloo, Ontario N2L 3G1, Canada.
authors.forename: J H
authors.initials: JH
authors.lastname: Teichroeb
authors.forename: J A
authors.initials: JA
authors.lastname: Forrest
authors.forename: L W
authors.initials: LW
authors.lastname: Jones
mesh_terms: D000327:Adsorption; D000818:Animals; D001703:Biophysics / Q000379:methods; D002417:Cattle; D006046:Gold / Q000737:chemistry*; D007700:Kinetics; D053768:Metal Nanoparticles / Q000737:chemistry*; D008968:Molecular Conformation; D053758:Nanoparticles / Q000737:chemistry; D054118:Nanospheres / Q000737:chemistry*; D010825:Physics; D011487:Protein Conformation; D011489:Protein Denaturation; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D013053:Spectrophotometry / Q000379:methods
chemical_list: D012710:Serum Albumin, Bovine; D006046:Gold