Preparation of TiTannic gels. Full details of the diverse hydrogels and organogels that can be prepared using the TiTannic gel system, including under which conditions and compositions different gelation times can be achieved, has been previously described. Briefly, a 50 mg mL -1 TA solution was prepared in deionized water and the pH was raised to ~7 using NaOH (1 M, aq.). Separately, DMSO was added to Ti-BALDH until a final concentration of 20 vol.%, this Ti-BALDH/DMSO mixture is the Ti IV solution. TA solution and Ti IV solution was mixed through vortexing at a TA:Ti IV molar ratio of around 1:2.5 for a gelation time around ~15 minutes. See Section S1 in the supporting information for additional details including a step-by-step protocol.