Physico-chemical characterization of functionalized polypropylene hernia-repair biomaterials

Polypropylene (PP) is the most common surgical non-absorbable material used in hernioplasty and recently its use has been improved coupling PP in form of meshes functionalized with absorbable compounds which progressively reduce the prosthesis weight favoring the new cellular tissues growth. Since one of the main problem in the use of meshes is the onset of post-transplant infections, the present study concerns an attempt of preparation and characterization of a novel surgical mesh with antibiotic properties. The purpose can be achieved using chitosan as antibiotic bioresorbable polymer covering lightweight polypropylene mesh. Chitosan is commercially available and is very cheap, with excellent biological properties such as non-toxicity, biocompatibility and biodegradability. Moreover, it possesses antimicrobial activity to many Gram-positive (e.g. Staphylococcus Aureus) and Gram-negative (e.g. Escherichia Coli) bacteria. The crucial point in the final product preparation is the modification of the PP fibers surface in order to enhance the interactions PP-chitosan. A treatment carried out in oxidizing atmosphere by an atmospheric pressure plasma device (APP-DBD) should produce a controlled oxidation of the fibers generating species (hydroperoxides, alcohols, carboxylic acids) capable to form hydrogen bonds with the chitosan polar groups. The chemico-physical properties of the meshes before and after plasma treatment and the effect of different plasma treatments on chitosan loading will be described.