Bovine Serum Albumin Enhances Silver Nanoparticle Dissolution Kinetics in a Size- and Concentration-Dependent Manner

Abstract

The dissolution of silver nanoparticles (AgNPs) to release Ag(I)(aq) is an important mechanism in potentiating AgNP cytotoxicity and imparting their antibacterial properties. However, AgNPs can undergo other simultaneous biophysicochemical transformations, such as protein adsorption, which can mediate AgNP dissolution behaviors. We report the comprehensive analysis of AgNP dissolution and protein adsorption behaviors with monolayer surface coverage of AgNPs by bovine serum albumin (BSA). AgNP dissolution rate constants, k dissolution , were quantified over several particle sizes (10, 20, and 40 nm) and BSA concentrations (0−2 nM) using linear sweep stripping voltammetry. Across all particle sizes, the dissolution rate constant increased with increasing BSA concentrations. However, protein-enhanced dissolution behaviors were most pronounced for 10 nm AgNPs, which exhibited 3.6-fold and 7.7-fold relative enhancement when compared to 20 and 40 nm AgNPs, respectively. Changes to AgNP surface properties upon interaction with BSA were monitored using dynamic light scattering and zeta potential measurements, while BSA−AgNP complex formation was evaluated using UV−vis spectroscopy and circular dichroism spectroscopy. A subtle increase in the BSA−AgNP association constant was observed with an increase in the AgNP size. Together, these results suggest that the AgNP size dependence of BSA-enhanced dissolution of AgNPs is possibly mediated through both displacement of Ag(I)(aq)-loaded BSA by excess protein in the bulk solution and minimized accessibility of the AgNP surface because of BSA adsorption.

Distinguishing Nanoparticle–Nanoparticle Interactions between Gold and Silver Nanoparticles Controlled by Gemini Surfactants: Stability of Nanocolloids

“…However, NP surface-coated species are usually surface-active molecules with dual affinity to interact simultaneously with the liquid and solid phases; , therefore, they are prone to undergo hydrophilic and hydrophobic interactions. Such interactions significantly depend on several solution properties such as concentration, temperature, ionic strength, and so forth. − Concentration is the most important factor in view of the load-carrying ability of NPs for a specific application. Thus, high concentration of NPs makes them easily vulnerable for NP–NP interactions, , which are usually the manifestation of both hydrophilic and hydrophobic interactions.…”

Application of Localized Surface Plasmon Resonance Spectroscopy to Investigate a Nano–Bio Interface

“…Adsorption constants obtained by two complementary approaches yielded similar results, with slightly lower standard deviations for the LSPR method. A previously published work of Boehmler et al 32 on the interactions between BSA and AgNPs using the LSPR method showed that adsorption constants increased with NP diameter. Contrarily, Dennison et al 41 obtained a higher adsorption constant for BSA onto the AuNP surface compared to our results, even though they used smaller AuNPs.…”

“…, aggregation) or changes of the immediate environment (due to ligand adsorption). − Tracking the spectral changes following the exposure of NPs (either immobilized on a chip or free in solution) to the analyte of interest is the basis of the LSPR method in biosensing. The technique can be used to monitor parameters of the nano–bio interaction such as protein binding kinetics on nanosurfaces. − The LSPR technique is a sensitive, label-free, simple, and cheap technique that offers detection, quantification, and/or binding characterization of different analytes without the need for sample purification. ,, Nevertheless, the use of LSPR for determining NPs–protein binding affinity and kinetics has still not been widely applied.…”

Beyond the Nanomaterials Approach: Influence of Culture Conditions on the Stability and Antimicrobial Activity of Silver Nanoparticles

“…43−45 Also, proteins may adsorb Ag(I) and dissolve the AgNPs. 32,46 Additionally, it has been widely reported that the AgNP−protein interaction leads to the "protein corona" formation around the AgNPs. 47 Protein corona induces changes in the AgNPs' traits, such as size, stability, and even in the way they interact with cells.…”