Biomedical Engineering Reference
In-Depth Information
Chapter 2
Nanoparticle and Protein Corona
Abstract
Nanoparticles and other nanomaterials are increasingly considered for
use in biomedical applications such as imaging, drug delivery, and hyperthermic
therapies. Thus, understanding the interaction of nanomaterials with biological
systems becomes key for their safe and efficient application. It is increasingly
being accepted that the surface of nanomaterials would be covered by protein
corona upon their entrance to the biological medium. The biological medium will
then see the achieved modified surface of nanomaterials, and therefore further
cellular/tissue responses depend on the composition of corona. In this chapter, we
describe the corona variations according to the physicochemical properties of
nanomaterials (e.g., size, shape, surface charge, surface functional groups, and
hydrophilicity/hydrophobicity). Besides the nanomaterials' effects, the role of
environment factors, such as protein source and slight temperature variations, is
discussed in details.
After intravenous administration, blood is the first physiological environment that a
nanomaterial “sees.” Blood plasma contains several 1,000 different proteins with
12 order of magnitude difference in the concentration of these proteins [
1
]. In
addition to the proteins, lipids are also available in blood plasma. Therefore, upon
injection of nanoparticles inside the blood, there is a competition between different
biological molecules to adsorb on the surface of the nanoparticles. In the initial
stage, most abundant proteins are adsorbed on the surface; however, over the time
they will be replaced by higher affinity proteins (Vroman's effect [
4
]).
The structure and composition of the protein corona depends on the physico-
chemical properties of the nanomaterial (size, shape, composition, surface func-
tional groups, and surface charges), the nature of the physiological environment
(blood, interstitial fluid, cell cytoplasm, etc.), and the duration of exposure. The
protein corona alters the size and interfacial composition of a nanomaterial, giving
it a new biological identity which is what is seen by cells. The biological identity
determines the physiological response including agglomeration, cellular uptake,
circulation lifetime, signaling, kinetics, transport, accumulation, and toxicity.
