Tailoring hydrogel microstructure via phase separation and kinetic trapping

Control of the microstructure of a biopolymeric phase-separated system is presented as part of an effort to develop a novel platform for controlled drug release. Under certain conditions, aqueous mixtures of biopolymers exhibit thermodynamic incompatibility and separate into distinct phases, each concentrated in one component and poor in the other. Upon initiation of phase separation (PS), droplets of one phase, the included phase, appear and ripen over time such that shared surface area with the continuous phase is minimized. Gelation is a means of halting droplet growth prior to bulk PS (BPS). The purpose of this research is to establish the means to dictate the microstructure of a PS system by: (i) understanding the effects of biopolymer concentration on PS temperature, TPS; (ii) modeling the growth of droplets within the included-phase; (iii) examining the efficacy of gelation as a means of trapping microstructure and (iv) investigating the characteristic microstructures of biopolymer systems undergoing a two-step temperature quench.