Physical−Chemical Aspects of Protein Corona: Relevance to in Vitro and in Vivo Biological Impacts of Nanoparticles

Abstract

It is now clearly emerging that besides size and shape, the other primary defining element of nanoscale objects in biological media is their long-lived protein ("hard") corona. This corona may be expressed as a durable, stabilizing coating of the bare surface of nanoparticle (NP) monomers, or it may be reflected in different subpopulations of particle assemblies, each presenting a durable protein coating. Using the approach and concepts of physical chemistry, we relate studies on the composition of the protein corona at different plasma concentrations with structural data on the complexes both in situ and free from excess plasma. This enables a high degree of confidence in the meaning of the hard protein corona in a biological context. Here, we present the protein adsorption for two compositionally different NPs, namely sulfonated polystyrene and silica NPs. NP-protein complexes are characterized by differential centrifugal sedimentation, dynamic light scattering, and zeta-potential both in situ and once isolated from plasma as a function of the protein/NP surface area ratio. We then introduce a semiquantitative determination of their hard corona composition using one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis and electrospray liquid chromatography mass spectrometry, which allows us to follow the total binding isotherms for the particles, identifying simultaneously the nature and amount of the most relevant proteins as a function of the plasma concentration. We find that the hard corona can evolve quite significantly as one passes from protein concentrations appropriate to in vitro cell studies to those present in in vivo studies, which has deep implications for in vitro-in vivo extrapolations and will require some consideration in the future.

Investigating the Interaction of Cellulose Nanofibers Derived from Cotton with a Sophisticated 3D Human Lung Cell Coculture

“…In addition, the role of protein interaction and exchange on the surface of CCNs should be examined, because this is known to significantly affect the interaction of different nano-objects with mammalian cells. 35 The manner in which nano-objects interact with cells in vitro has been shown to significantly affect the subsequent cellular response. 34 Our investigation of the cellulose nanowhiskers' ability to cause cellular damage (cytotoxicity) by the release of the cytosolic enzyme lactate dehydrogenase (LDH) showed that at a low CCN concentration (0.005 mg 3 mL À1 ) no significant (p > 0.05) cytotoxicity occurred after 24 h of exposure on the apical layer of the triple cell coculture model ( Figure 3A).…”

Nanoparticle Adhesion to the Cell Membrane and Its Effect on Nanoparticle Uptake Efficiency

“…[17][18][19][20][21][22] When cells are exposed to NPs it is therefore, in realistic circumstances, typically not the bare NP surface that interacts with the cell but the NP-biomolecular corona complex. [23][24][25] Consequently, it becomes interesting to correlate NP uptake not to properties of the bare NP, but to properties of the NP-biomolecular corona complex. 26,27 NP uptake begins with an initial adhesion of the NP to the cell and interactions with the lipids, proteins and other components of the cell membrane.…”

Effects of the Presence or Absence of a Protein Corona on Silica Nanoparticle Uptake and Impact on Cells

“…[13][14][15] The corona is a very selective layer of proteins and other biomolecules, which strongly adsorbs on the nanoparticle surface for time scales longer than nanoparticle uptake in cells, thus constitutes the new complex unit interacting with the cellular machinery. [16][17][18][19][20][21][22] The formation of a corona affects the material properties also by simply lowering the surface free energy of the bare material.…”