Stealth Polymeric Vesicles via Metal-Free Click Coupling

Biomacromolecules (Impact Factor: 5.75). 08/2013; 14(9). DOI: 10.1021/bm400940h
Source: PubMed


The strain-promoted azide-alkyne cycloaddition represents an optimal metal-free method for the modular coupling of amphiphilic polymer blocks. Hydrophilic poly(oxazoline) (PMOXA) or poly(ethyleneglycol) (PEG) A-blocks were coupled with a hydrophobic poly(siloxane) B-block to provide triblock copolymers capable of self-assembling into vesicular nanostructures. Stealth properties investigated via a complement activation assay revealed the superior in vitro stealth attributes of polymeric vesicles synthesized via a metal-free approach to those coupled via the widely used copper-catalyzed click method. Furthermore, the ability to change a single parameter, such as the hydrophilic block, allowed the direct comparison of the biocompatibility properties of triblock copolymers containing PMOXA or PEG. Our studies convincingly demonstrate the need for a metal-free approach, both in preventing cytotoxicity while imparting optimal stealth properties for potential biomedical applications.

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