Optimum dose of chitin and chitosan for organization of non-woven fabric in the subcutaneous tissue

This study was performed to evaluate tissue reactions induced in rats by polyester non-woven fabric (NWF, 1 X 1 cm(2), 0.6 mm thick) impregnated with chitin or chitosan suspension ranging from 0.1 to 50 mg/ml (chitin-NWF, chitosan-NWF) and NWF impregnated with phosphated buffer solution (control). Evaluations were based on macroscopic and microscopic observations, and image analysis of histological samples stained with Alcian blue, Safranin O, and Masson trichrome for identifying glycosaminoglycan, proteoglycan, and collagen, respectively. Macroscopically, the NWFs impregnated with higher concentrations of chitin (50 mg/ml) and chitosan (10 mg/ml) suspensions evoked more strong reactions than those impregnated with weaker concentrations of chitin (1.0 and 10 mg/ml) and chitosan (0.1 and 1.0 mg/ml) suspensions and were characterized by thickening of the NWF at Day 7 of the implantation. There was swelling and accumulation of exudates in the NWF impregnated with 50 and 10 mg/ml of chitin and chitosan suspensions, respectively. However, in microscopic examination, organization of the NWF implants was found to be superior in the NWF impregnated with weaker suspensions of chitin and chitosan. The chitin groups at higher concentrations showed higher value than the controls in the sections prepared with Alcian blue staining, but lower values in the sections prepared by Safranin O staining. In the Masson's trichrome staining, the chitin groups at lower concentrations showed lower values than the control. The chitosan groups were similar to the control in all special stainings. (C) 2001 Elsevier Science Ltd. All rights reserved.