dc.description.abstract | After parenteral administration, nanoparticles interact with different proteins,
forming a shell called corona, which further influence nanoparticles’ biodistribution. Protein
adsorption is affected by particle size and shape, but also by molecular interactions of
chemical groups from the particle surface and amino-acid residues of the proteins. In human
plasma, albumin is the most abundant protein so it is frequently used for the investigation of
protein-nanoparticle interactions (1). In this study we investigated the attachment of bovine
serum albumin (BSA) to recently developed nanocrystals (2) of DK-I-56-1 (7-methoxy-2-
(4-methoxy-d3-phenyl)-2,5-dihydro-3H-pyrazolo[4,3-c]quinolin-3-one), stabilized by
polysorbate 80 (NS2) or the combination of polysorbate 80 and poloxamer 407 (NS4).
Nanocrystal dispersion was incubated in medium containing 0.1% or 1% BSA in phosphate
buffer saline (pH 7,4) at 37 °C for 1 h. Particle size analysis was conducted by dynamic light
scattering in 10 min interval, at 37 °C on Zetasizer ZS90 (Malvern Instruments Ltd.,
Worcestershire, UK). It was shown that albumin adsorption was influenced by the
nanocrystal formulation and albumin concentration, but not incubation time. In a medium
with 0.1% BSA, no particle size difference was noticed in either formulation. However, in
case of NS2, after the addition of 1% albumin, particle size and particle size distribution
increased, which indicated albumin binding. On the other hand, in formulation NS4, with
higher albumin concentration two peaks were visible, one from the free albumin, and one
from nanocrystal particles. Therefore, it could be concluded that the affinity of albumin was
influenced mainly by the interaction with the nanocrystal stabilizers. | sr |