title: Effect of gold nanosphere surface chemistry on protein adsorption and cell uptake in vitro.
abstract: Gold nanoparticles exhibit unique spectral properties that make them ideal for biosensing, imaging, drug delivery, and other therapeutic applications. Interaction of gold nanoparticles within biological environments is dependent on surface characteristics, which may rely on particular capping agents. In this study, gold nanospheres (GNS) synthesized with different capping agents--specifically citric acid (CA) and tannic acid (TA)--were compared for serum protein adsorption and cellular uptake into a lung epithelial cell line (A549). Both GNS samples exhibited noticeable protein adsorption based on surface charge data after exposure to serum proteins. Light scattering measurements revealed that GNS-CA-protein composites were smaller and less dense compared to GNS-TA-protein composites. The cell uptake characteristics of these nanoparticles were also different. GNS-CA formed large clusters and elicited high uptake, while GNS-TA were taken up as discrete particles, possibly through nonendosomal mechanisms. These results indicate that the capping agents used for GNS synthesis result in unique biological interactions.
authors.affiliation: Air Force Research Laboratory, Wright Patterson AFB, OH, USA.
authors.forename: Amrita
authors.initials: A
authors.lastname: Mukhopadhyay
authors.forename: Christin
authors.initials: C
authors.lastname: Grabinski
authors.forename: A R M Nabiul
authors.initials: AR
authors.lastname: Afrooz
authors.forename: Navid B
authors.initials: NB
authors.lastname: Saleh
authors.forename: Saber
authors.initials: S
authors.lastname: Hussain
mesh_terms: D000327:Adsorption; D002460:Cell Line; D006046:Gold / Q000737:chemistry*; D006801:Humans; D053768:Metal Nanoparticles / Q000737:chemistry*; D054118:Nanospheres / Q000737:chemistry*; D010316:Particle Size; D012709:Serum Albumin / Q000737:chemistry*
chemical_list: D012709:Serum Albumin; D006046:Gold