A hyperspectral and toxicological analysis of protein corona impact on silver nanoparticle properties, intracellular modifications, and macrophage activation

Abstract

Jonathan H Shannahan,1 Ramakrishna Podila,2,3 Jared M Brown1 1Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, The University of Colorado Anschutz Medical Campus, Aurora, CO, 2Department of Physics and Astronomy, Clemson University, Clemson, 3Clemson Nanomaterials Center and COMSET, Clemson University, Anderson, SC, USA Abstract: The inevitable adsorption of biomolecules on nanomaterials results in the formation of a protein corona (PC), which modifies the nanoparticle (NP)–cell interface resulting in modified uptake, activity, clearance, and toxicity. While the physicochemical properties of the NP govern the composition of PC, the formation of PC in turn alters the characteristics of the NP by imparting a new unique “biological” identity. To assess how the PC influences AgNP properties, intracellular modifications, and cellular responses, we utilized a combination of hyperspectral and toxicological analyses. AgNPs were coated with a complex PC (multiple proteins, eg, 10% fetal bovine serum) or a simple PC (single protein, eg, bovine serum albumin [BSA]) and evaluated by hyperspectral and dynamic light scattering for modifications in AgNP properties. Mouse macrophages were exposed to AgNPs with PCs and examined for differences in uptake, cytotoxicity, and cell activation. Hyperspectral imaging revealed intracellular modifications to AgNPs that were found to spectrally match alterations in AgNPs following incubation in lysosomal fluid. Addition of the PC influenced AgNP uptake and cytotoxicity; however, hydrodynamic size and surface charge did not contribute to these responses. Assessments of all endpoints demonstrated differences between complex and BSA PC, suggesting that these responses are not purely driven by the primary protein component of the complex PC (ie, BSA). Alterations in cellular–NP uptake/interactions may be driven through cell surface receptor recognition of protein constituents that make up the PC rather than the physicochemical differences in AgNPs. Keywords: nanomaterials, biocorona, hyperspectral imaging, darkfield microscopy