Using pyrocatechol to initiate competing ligand-mediated gel disassembly has previously been reported. Photos of the vials were taken first with all vials containing only PBS (time point = 0 hours) and then at pre-determined time intervals (5 minutes, 1 hour and 24 hours) after replacement of PBS in three of the four vials with NaOH, HCl or pyrocatechol aqueous solutions. Results are presented in Figure .