Sistemi a base di chitosano per applicazioni farmacologiche

This PhD work is about the implementation of innovative chitosan-based Drug Delivery Systems (DDSs) for the cure of periodontal disease. Current treatment of this pathology consists of localized administrations of antibiotic and anti-inflammatory drugs, but repeated therapeutic sessions have negative consequences on the patient’s quality of life. In the present work novel potential drug delivery systems have been investigated with the aim of administering drugs and simultaneously promoting the regeneration of damaged tissues. To this purpose chitosan has been chosen because of its unique properties including biocompatibility, biodegradability, mucoadhesivity, antimicrobial and wound-healing capabilities. Three types of chitosan-based systems have been studied: microbeads with internal sponge-like architecture, obtained by drop-to-drop coagulation of an acetic chitosan solution in a EtOH/ NH3/H2O bath, films obtained by drop-casting, and membranes prepared by electrospinning from an aqueous mixture of chitosan and poly(ethylene oxide). The uptake and release properties of these systems have been tested with the antibiotic drug Doxycycline hydrochloride (DC) and the anti-inflammatory drug Triamcinolone acetonide (TC). Freundlich and pseudo second-order kinetic equations have been applied to describe the processes at varying the drug concentrations. The most relevant results obtained from this PhD work show delayed drug release by microbeads and films, compatible with a controlled DDS behaviour, and highly increased DC uptake by electrospun membranes, likely due to their very porous structure.