Figure 3. Permeation profiles of acetaminophen, FD-150, and insulin for porcine and human sclera. Profiles for acetaminophen (A), FD-150 (B), and insulin (C) through porcine (○)  and human (●) sclera are shown. Open squares (□) in panel A indicate the permeation profile of acetaminophen through fresh porcine sclera. Transscleral fluxes obtained for all three molecules tested were higher for human sclera. In particular, the fluxes through human sclera were 2 times greater than through pig sclera in the case of acetaminophen and insulin, and 3 times greater in the case of FD-150. Permeability of acetaminophen through fresh porcine sclera confirmed that the freezing procedure did not have any effect on tissue permeability. Mean value ±SEM