title: Effects of surface compositional and structural heterogeneity on nanoparticle-protein interactions: different protein configurations.
abstract: As nanoparticles (NPs) enter into biological systems, they are immediately exposed to a variety and concentration of proteins. The physicochemical interactions between proteins and NPs are influenced by the surface properties of the NPs. To identify the effects of NP surface heterogeneity, the interactions between bovine serum albumin (BSA) and gold NPs (AuNPs) with similar chemical composition but different surface structures were investigated. Different interaction modes and BSA conformations were studied by dynamic light scattering, circular dichroism spectroscopy, fluorescence quenching and isothermal titration calorimetry (ITC). Depending on the surface structure of AuNPs, BSA seems to adopt either a "side-on" or an "end-on" conformation on AuNPs. ITC demonstrated that the adsorption of BSA onto AuNPs with randomly distributed polar and nonpolar groups was primarily driven by electrostatic interaction, and all BSA were adsorbed in the same process. The adsorption of BSA onto AuNPs covered with alternating domains of polar and nonpolar groups was a combination of different interactions. Overall, the results of this study point to the potential for utilizing nanoscale manipulation of NP surfaces to control the resulting NP-protein interactions.
authors.affiliation: Department of Geology, Baylor University , One Bear Place #97354 Waco, Texas 76798, United States.
authors.forename: Rixiang
authors.initials: R
authors.lastname: Huang
authors.forename: Randy P
authors.initials: RP
authors.lastname: Carney
authors.forename: Kaoru
authors.initials: K
authors.lastname: Ikuma
authors.forename: Francesco
authors.initials: F
authors.lastname: Stellacci
authors.forename: Boris L T
authors.initials: BL
authors.lastname: Lau
mesh_terms: D000327:Adsorption; D000818:Animals; D002151:Calorimetry; D002417:Cattle; D002942:Circular Dichroism; D006046:Gold / Q000737:chemistry; D006801:Humans; D007700:Kinetics; D008027:Light; D053768:Metal Nanoparticles / Q000737:chemistry; D053758:Nanoparticles / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D025941:Protein Interaction Mapping; D017433:Protein Structure, Secondary; D012542:Scattering, Radiation; D012710:Serum Albumin, Bovine / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D055672:Static Electricity; D013499:Surface Properties; D013816:Thermodynamics
chemical_list: D012710:Serum Albumin, Bovine; D006046:Gold