2.6.3. Ex Vivo Adhesion Studies

Patch adhesion force was assessed using pig skin samples (from shoulder region), obtained from large white pigs weighing ∼165–175 kg, furnished by Veterinary Service of ASL N.1 Città di Castello (Perugia, Italy), and used within 12 h from pig death [22]. The ex vivo adhesion force was measured by a dynamometer (Didatronic, Treni, Italy). The patch (2 × 2 cm) was attached to support, connected to the dynamometer, using cyanoacrylate glue. A piece of porcine skin tissue (4 × 4 cm) was fixed with cyanoacrylate glue on the surface of glass support placed in a thermostatic bath at 32 ◦C ± 0.5. The free side of the patch was wetted with 100 μL of phosphate buffer pH 5.50 and put in contact with the skin sample by applying a light force for 20 s. The force necessary for patch detachment to skin was measured and expressed as the average of three measurements (n = 3).
