ABSTRACT
Poly(2-oxazoline)s (POx) have the same repeated C-C heteroatomic chains, which is very similar to polyethylene glycol (PEG), so POx have the similar properties to PEG, such as hydrophilicity and flexibility and low immunogenicity, etc. However, POx also possesses pH-sensitivity, thermo-responsibility, and does not interfere with the cellular uptake of nanocarriers, which highlights the potential of POx as an ideal alternative to PEG for constructing and modifying liposomes, micelles, polymer-drug conjugates and other nanocarriers. Among the POx, the chemical nature of poly(2-ethyl-2-oxazoline) (PEOZ) is the most active, which is the most widely used. In this paper, the synthesis of POx serial derivatives and their application in drug delivery systems were reviewed, mainly focused on PEOZ.