Temperature-responsive polymer vesicles

The era of biomimetic peptide- and sugar-based polymer vesicles has just begun and seems very promising. Bioinspired vesicles are mainly applied for drug deliv-ery/release and the fabrication of composite materials, but could readily be used for biomimetic materials science, biomineralization, and so on. Especially interesting are smart vesicles changing properties in response to an external stimulus (temperature, pH, ions). 

A recent report characterized a randomly alkylated copolymer of NIPAAm, methacrylic acid, and Ar-vinyl-2-pyrroli-done in terms of its pH- and temperature-triggered conformational change (118). The polymer was complexed to liposomes so that pH-responsive vesicles would be produced. The polymer underwent a coil-to-globule phase transition... 

Temperature and pH responsiveness has been also recorded for a non covalently bonded DHBC inclusion complex, namely P4VP-PNIPAM [33]. The non-covalently connected copolymer tends to create micelles with PNIPAM cores at low pH values and at elevated temperatures. However, at room temperature and high pH values, the polymer formed vesicles instead of core-shell micelles. The formation of vesicles was confirmed by a number... 

Bilayer lipid structures are known to transform between a variety of morphologies. These transformations are controlled by the geometry or the chemistry of the molecular structures and by the presence of external stimuli. Giant vesicles, in the form of spherical lipid bilayers, are used as simplified models of biological cells. Their in vitro study using optical microscopy allows their responses to be observed when exposed to stresses such as temperature changes, UV irradiation, electric or osmotic shocks, or the addition of an external agent, such as amphiphilic polymers. 

---