Biomedical Engineering Reference
In-Depth Information
minutes to hours, more important for the in vivo behavior of intravenously injected
particles, the protein adsorption patterns were qualitatively similar to each other.
Furthermore, the relative amount of major proteins, such as apolipoproteins, fibrino-
gen, and albumin, kept constant over time. The amount of adsorbed immunoglobulins
increased with incubation time. The knowledge of the protein adsorption patterns and
kinetics on USPIO nanoparticle surfaces can be an important step on the way to tailor-
made targeted iron oxide nanoparticles. Thus, when processes of protein adsorption
and the corresponding body distribution are known, one can design USPIO with
optimized physicochemical surface properties, which are expected to automatically
adsorb the proteins required for localization in a certain tissue, i.e., these iron oxide NP
are “self-targeted” to the desired site of action.
2.4 Parameters Affecting Protein Corona
Although there is a growing agreement that the protein corona is what is seen by
cells, yet, more research is required to better understand why any nanomaterial
chooses those particular proteins. Various parameters such as nanoparticle size,
shape, curvature, surface charge (zeta potential), solubility, surface modification,
and route of administration of nanoparticles to the body affect the composition,
thickness, and conformation of protein corona. These parameters have been
reviewed recently by various groups [
6
,
7
,
11
,
19
]. Among the nanoparticle (NP)
parameters which affect the protein corona, the surface properties such as
hydrophobicity and surface charge have more significant role than other parameters
[
5
]. In the following section, the role of each parameter is explained with more
details. Better understanding of role of each physicochemical parameter on the
protein corona is promising for design of targeting nanomaterial, long-circulating
drug carriers, or for decreasing the toxicity.
Casals et al. [
20
] studied the time evolution of the protein corona in Au NPs.
These NPs of different sizes (4-40 nm) stabilized electrostatically with (1) citrate
ions and with a self-assembled monolayer (SAM), (2) mercaptoundecanoic acid
(negative surface charge), and (3) aminoundecanethiol (positive surface charge).
They explored the formation of the protein corona after exposure of Au NP to cell
culture media containing 10 % of fetal bovine serum (FBS). Under in vitro cell
culture conditions, zeta potential measurements, UV-vis spectroscopy, DLS, and
TEM analysis were used to monitor the time evolution of the protein corona. As
expected, the redshift of the surface plasmon resonance peak, as well as the drop of
surface charge and the increase of the hydrodynamic diameter indicated the conju-
gation of proteins to NP. An evolution from a loosely attached toward an irrevers-
ible attached protein corona over time was observed. Mass spectrometry of the
digested protein corona revealed albumin as the most abundant component which
suggests an improved biocompatibility.
