“Spherical Gold Nanoparticles Impede the Function of Bovine Serum Albumin In vitro” is now online

Update (December 19, 2013): the article is now Open Access and has a functional DOI.

Update (December 1, 2013): we have submitted payment for Open Access publishing, and hope to have this processed as soon as possible. In the meantime, please find a free courtesy corrected proof available, hosted by chrisdieni.com. The DOI is still not yet functional, but the article is also available at the journal’s website via this link: http://www.scitechnol.com/spherical-gold-nanoparticles-impede-the-function-of-bovine-serum-albumin-in-vitro-a-new-consideration-for-studies-in-nanotoxicology-5suF.php?article_id=1506

Our recently-accepted publication, “Spherical gold nanoparticles impede the function of bovine serum albumin in vitro: a new consideration for studies in nanotoxicology” is now available on the SciTechnol publisher’s website.

Journal of Nanomaterials and Molecular Nanotechnology has now become a subscription journal and as such, articles are behind a paywall, including ours. However, we have received an invitation to make our article “Open Access,” and hope to have this option processed as quickly as possible.

Congratulations once again to all authors of this manuscript: Chris Stone, Luke Armstrong, Neal Callaghan, and Tyson MacCormack.

Spherical Gold Nanoparticles Impede the Function of Bovine Serum Albumin In vitro: A New Consideration for Studies in Nanotoxicology

Abstract

Suspensions of bovine serum albumin (BSA) and spherical gold nanoparticles were analyzed to determine if gold nanoparticles (nAu) affect the ligand binding properties of BSA. A range of diameters of nAu with a carboxylic acid capping agent (nAu-cap) were tested, along with nanoparticles conjugated to amine (nAu-NH₃⁺) and carboxyl (nAu-COO^–) functional groups via a covalent polymer bridge. All nAu tested were found to affect BSA conformation as determined by intrinsic tryptophan fluorescence. Smaller diameters of nAu-cap (30-50 nm), along with nAu-NH₃⁺ and nAu-COO^–, impeded the binding of 8-anilino-1-napthalenesulfonic acid (ANS) to BSA. Similarly, smaller diameters of nAu-cap tended to impede oleic acid binding to BSA, with a linear negative correlation observed between nAu-cap diameter and the dissociation constant (K_D) of oleic acid over the range of 40-80 nm. 80 nm nAu-cap impeded butanoic acid binding, and necessitated a high-resolution fluorescence assay. As with oleic acid, smaller diameters of nAu-cap tended to impede ibuprofen binding, but no significance could be established. nAu- NH₃⁺ and nAu-COO^– reduced the binding of thyroxine and bilirubin to BSA, with nAu-COO^– having a more pronounced effect in both cases. Visible-light spectral scans determined that interactions between BSA and different sizes of nAu did not change significantly over the course of 1 week, as established by relatively stable wavelengths of maximum absorbance. In order to isolate stronglyinteracting BSA oligomers, irreversible BSA aggregates, or strong BSA-nAu complexes induced by recruitment of BSA into the protein corona, BSA-nAu-cap suspensions were subjected to centrifugal filtration and native-PAGE, however, this methodology failed to detect any altered distribution of higher-molecular weight species of BSA compared to control (free of nAu), suggesting that any proteinprotein or protein-nAu interactions that contribute to these altered properties of BSA are not irreversible and do not withstand high g-forces and/or electrophoresis.