Zusammenfassung
To counter the undesired colloidal destabilization of nanoparticles in
biologically-compatible media of high ionic strength (i.e. NaCl,
phosphate buffer), polymers can be added to nanoparticle suspensions
that will be used in biomedical applications. In these suspensions,
polymers can promote high colloidal stability by manifestation of steric
and/or depletion forces. However, little is known about the influence of
these polymers on the interactions between nanoparticles and the
biological components of the organism, such as proteins and cells. In
this work, it was shown that the addition of the polymers (i)
Pluronic-F127 (PF127), (ii) polyethylene glycol (PEG) of different
molecular weights 1.5, 12 and 35 kDa and (iii) the protein bovine serum
albumin (BSA) on colloidal silica nanoparticles (CSNPs; 135 nm)
dispersed in phosphate-buffered saline (PBS) largely alter their
colloidal stability through different mechanisms. Although all polymers
were adsorbed on the CSNP surface, BSA maintained the CSNP dispersion in
the medium by electrosteric stabilization mechanisms, while PEG and
PF127 led to the occurrence of depletion forces between the particles.
In addition, it was found that the interactions between polymers and
CSNPs did not prevent proteins to access the nanoparticles' surface and
have minimal effect on the formation of the protein corona when they
were incubated in human blood plasma. On the other hand, BSA had a
greater effect on the CSNP protein corona profile compared to other
polymers (PEG and PF127). Together, these results confirm that
biocompatible polymers PEG and PF127 can be used as colloidal
stabilizing agents for nanoparticles since they preserve the
accessibility of biomolecules to the nanoparticle surface, and they have
little effect on the protein corona composition.
Nutzer