Emergent membrane-affecting properties of BSA–gold nanoparticle constructs

Abstract

By adsorbing bovine serum albumin (BSA) on gold nanoparticles (Aunps) with diameters 30 nm and 80 nm, different degrees of protein unfolding were obtained. Adsorption and adlayer conformation were characterized by UV-vis spectroscopy, ζ-potential measurements, steady-state and time-resolved fluorescence. The unfolding was also studied using 1-anilino-8-naphthalene sulfonate (ANS) as an extrinsic probe, showing that BSA unfolds more on 80 nm Aunp than on 30 nm Aunp. Langmuir monolayer studies using two distinct methods of introducing the BSA and BSA-Aunp constructs accompanied with Brewster Angle Microscopy (BAM) and Digital Video Microscope (DVM) imaging demonstrated that BSA-Aunp constructs induce film miscibility with L-α-phosphatidylethanolamine not seen for BSA or Aunp alone. The changes induced by partial unfolding clearly give better film-penetration ability, as well as disruption of liquid crystalline domains in the film, thereby inducing film miscibility. Gold or protein only does not possess the nanoscale film-affecting properties of the protein-gold constructs, and as such the surface-active and miscibility-affecting characteristics of the BSA-Aunp represent emergent qualities.

Integrin-Specific Mechanoresponses to Compression and Extension Probed by Cylindrical Flat-Ended AFM Tips in Lung Cells

“…We can envision other mechanisms based on known properties of BSA. First, the surface charge of BSA could trigger mechanoresponses by inducing alterations in the membrane potential of A549 cells [48], [49], since changes in membrane potential can drive local alterations in actin polymerization large enough to modify cell stiffness according to a recent study [50]. Second, serum albumin is known to act as a carrier of aminoacids and other biomolecules in the blood by facilitating their binding owing to the presence of surface-charged groups and ionic/hydrophobic sites [48].…”

Nanoparticle‐stabilized microbubbles for multimodal imaging and drug delivery

“…In the second step, the protein and protein-NP film was compressed at a constant rate of 5 mm/min in order to probe the film characteristics and strength via the Injected protocol [23,24].…”

Self-assembly and characterization of transferrin–gold nanoconstructs and their interaction with bio-interfaces

“…15,18,19 The change in surface pressure upon injecting Tf and Tf-AuINT under an air/water interface (phosphate buffer, pH 7.4) is shown in Figure 4a. 15,18,19 The change in surface pressure upon injecting Tf and Tf-AuINT under an air/water interface (phosphate buffer, pH 7.4) is shown in Figure 4a.…”

“…[15][16][17][18][19] The average changes in trough area upon injection of Tf and Tf-AuINT under a precompressed phospholipid film are shown in Figure 4b. Consequently, only Tf and Tf-AuINT results are shown here.…”