AMADEus Seminar - Prof. Alexander Bismarck - Thursday 3 July 2014, 11:00 am - Aérocampus, Latresne

Making Polymers, Emulsions and Using Them as Injectable Scaffolds

Abstract: Emulsion templating has emerged as effective method to synthesise macroporous polymers with tailored pore morphology and physical properties. High or Medium Internal Phase Emulsions (HIPEs or MIPEs) with a continuous phase consisting of or containing monomers are used as templates for the preparation of very high porosity macroporous polymers, called poly(merized)M/HIPEs. However, this method typically requires the use of large amounts of surfactants or particulate emulsifiers to stabilize immiscible liquid phases and monomers and a crosslinker in the continuous minority phase to “solidify” the template, which may not be desirable for biomedical applications. We will show that polyHIPEs with porosity greater than 75% can be produced from inverse (oil-in-water) HIPEs solely stabilised using suitably modified biocompatible biopolymers. The biopolymer was modified by further grafting thermoresponsive polymers. The resulting copolymer acts simultaneously as emulsifier and thermoresponsive gelator and forms upon removal of the templating oil phase and water the bulk of the resulting polyHIPE. As can be expected, the resulting polyHIPEs are also thermoresponsive and injectable hydrogels, which remain intact when immersed into water at physiological temperature but do dissolve below their lower critical solution temperature. We will also demonstrate that cells grow into the scaffold and that this scaffold can be extruded through a needle, with no damage to the cells.