Information on the permeability of biological barriers is essential for the development of drug delivery systems as well as for toxicological tests. Unfortunately, the currently available in vitro system cannot efficiently mimic the structural and functional features of real physiological barriers, making it necessary to perform in vivo experiments before new products may become acceptable for human or veterinary medicine. In particular, the huge expansion of nanotechnology highlighted the lack of appropriate experimental models for evaluating the capability of nanocomposites to penetrate the different biological barriers. The main aim of our project is to set up an in vitro system to evaluate the penetration capability of drug-delivering nanovectors across various biological barriers. Therefore, a bioreactor developed by an Italian company, IVTech srl, to refine the standard in vitro cultures and increase their correlation with the reality, will be adapted to maintain explanted organs (skin, small intestine, blood vessels) in a dynamic environment mimicking the flow of physiological fluids. The bioreactor will be adapted to the explanted organs and a careful evaluation of organ vitality and integrity and cell stress will be performed by light and transmission electron microscopy as well as by biochemical tests. The setting-up of the new in vitro system will allow to investigate the kinetics of distribution and crossing through the three biological barriers -representative of the transdermal, oral and intravenous route of administration- of biocompatible polymeric, lipid- and silica-based nanoparticles designed for drug delivery.
Once properly validated, this novel in vitro apparatus will mostly be used for drug tests on surgically explanted tissues and organs (healthy and pathological) from operated human or animal patients, thus drastically reducing or even avoiding tests on laboratory animals, with an obvious decrease of the testing costs