In vitro cell cytocompatibility of diacid (3) and PolyMorphine (5). (A) Cell viability of the positive control (fibroblasts with cell culture media only), 3 (at 0.10 mg/mL), and 5 (at 0.10 mg/mL), no statistical differences at 95 % confidence level between the samples containing 3 and 5 and the positive control; Fluorescent microscopy images (green = viable cell and red = dead cells) of: (B) positive control, (C) negative control (fibroblasts with cell culture media and 5 % ethanol), (D) diacid 3, and (E) 5.