Recent advances in stealth coating of nanoparticle drug delivery systems

Abstract

Modifying surfaces of nanoparticles (NPs) with polyethylene glycol (PEG), the so-called PEGylation, is the most commonly used method for reducing premature clearance of NPs from the circulation. However, several reports point out that PEGylation may negatively influence the performance of NPs as a drug carrier. Alternative surface modification strategies, including substitute polymers, conditional removal of PEG, and biomimetic surface modification, may provide solutions for the limitations of PEG.

Fig. 1

(A) PEG structure; (B) model of PEGylated NPs.

Fig. 2

Schematic description of NP-based drug delivery to tumors. Arrows indicate steps negatively influenced by PEG layer on NP surface.

Fig. 3

Structures of poly(2-ethyl-2-oxazoline), PHEA, and HPMA.

Fig. 4

Structures of poly(sulfobetaine) and poly(carboxybetaine)

Fig. 5

Structure of hyperbranched polyglycerol.

Fig. 6

Structures of chitosan, heparin, and dextran.

Fig. 7

Poly(hydroxymethylethylene hydroxymethylformal)

Fig. 8

DePEGylation of NPs by cellular cues