Pharmaceutical nanotechnology: polymeric vesicles for drug and gene delivery

Improving the therapeutic index of medicines is a goal of drug delivery. Employing nanosystems that control drug biodistribution is one way of achieving therapeutic improvements, and polymeric bilayer vesicles are one such nanosystem. Polymeric vesicles, with the ability to transport drugs or genes, are prepared in one of two ways: i) the self-assembly of amphiphilic polymers and ii) the polymerisation of monomers, following self-assembly (polymerised vesicles). There are two types of self-assembling amphiphilic polymers: water-soluble polymers derivatised with hydrophobic pendant groups and amphiphilic block copolymers. Amphiphilic alkenes and alkynes are the main compounds that are used to make polymerised vesicles. This review discusses polymer architecture fundamentals that govern the self-assembly of polymers into vesicles, the fine control on vesicle size that is achievable with polymeric vesicles and the application of the vesicles to drug delivery.