Fig. 4

LDH activity measured from culture media collected 24 h after exposure of MC3T3-E1 cells to alginate or hyaluronic acid hydrogels at different polymer concentrations (1 %, 2 % and 3 %). High control (100 % cytotoxicity) was cell culture media from cells seeded on polyethylene terephthalate (PET) membrane inserts and incubated with PBS containing 1 % Triton X-100. Low control (0 % cytotoxicity) was cell culture media from cells seeded on PET membrane insert and incubated with PBS. Values represent the mean ± SEM. Significant differences were assessed by Student t test: p < 0.05balginate versus HA