Release of DOX from hydrogels loaded at 50 μg/ml, in 0.01M (a), 0.1M (b), and 1M (c) NaCl solutions. Total amount of DOX released from each hydrogel formulation in NaCl of different concentrations over 15 days (d). The amounts of DOX released from hydrogels are normalized to initial amounts of DOX loaded to each hydrogel formulation. (a) p<0.001 as compared to HG-0 in 0.01M NaCl solution, (b) p<0.001 as compared to HG-0 in 0. 1M NaCl solution, (c) p<0.001 as compared to HG-0 in 1M NaCl solution, (d) p<0.05 as compared to HG-5 in 0.01M NaCl solution, (e) p<0.05 as compared to HG-5 in 0.1M NaCl solution, (f) p<0.05 as compared to HG-5 in 1M NaCl solution.