Composite Gels Based on Poly (Vinyl alcohol) for Biomedical Uses

Nowadays, poly (vinyl alcohol) (PVA) hydrogels are being studied for several biomedical applications such as joint replacement, wound dressings and controlled drug-releasing devices, among others. Reinforced PVA hydrogels show good mechanical properties and are a suitable option to replace cartilages. Furthermore, these materials can prevent loss of body fluids, be a barrier against bacteria and also permeable to oxygen, for these all interesting properties, they are used like wound dressings. For drug delivery systems a material that can control the dose and release at the site of action is desirable, this can be accomplished using hydrogels, which are loaded with a drug, and then they can release it when an external stimulus (light, temperature, magnetic field, etc.) takes place. The aim of this work was to obtain composite hydrogels for the previously mentioned biomedical applications. Hydroxyapatite (HA) reinforced PVA gels were prepared for potential uses as cartilage replacement, HA improves the mechanical, tribological and fixing properties of the polymer, reaching values similar to that of the cartilages. For wound dressings, the hydrogel was reinforced with bentonite (clay) in order to increase the dimensional stability and antimicrobial properties. Gels with controlled drug release capability under magnetic stimulation (ferrogels) were also synthesized and characterized here.