Nanoparticle conjugation with polymer ligands: influence of surface modification on protein corona formation

The protein corona (an adsorbed protein layer on the surface of nanoparticles) unpredictably alters the pharmacokinetics and biodistribution of nanosomal forms in the body. In this study, the nanoparticle surface was modified with polymer ligands to investigate their influence on the protein corona formation of nanoparticles. Nanoparticles based on a copolymer of lactic and glycolic acids were synthesized using the single emulsion method. A technique for nanoparticle conjugation with poly-N-isopropylacrylamide (PNIPAM) and chitosan (Ch) was developed. The nanoparticle—ligand conjugates (ConjNP) were synthesized by the carbodiimide method; the target product was purified using gel exclusion chromatography. The resulting particles were characterized by Fourier transform IR spectroscopy and dynamic light scattering. It was found that the total protein concentration increased in the order of ConjNP—PNIPAM—NP—ConjNP—Ch. Thus, PNIPAM modification reduces the concentration of the protein layer on nanoparticles in comparison with unmodified ones. The revealed correlation is aimed at optimizing the design of nanosystems and improving their pharmacokinetic profiles.