Short Poster Lecture
Bacterial adhesion to bioactive materials that causes infection and poor tissue integration is one of the main problems that limits the lifetime of implants and medical devices. Besides that, the expanding population of bacteria that are resistant to common antibiotics is a global problem which is increasing sharply. Likewise one of the most serious problems connected to orthopedic surgery is that despite the use of hygienic protocols and preventive antibiotic prophylaxes, exists an increasing incidence of chronic wounds of limbs and feet that often lead to amputation. Therefore, localize control of bacteria and inflammation is needed.
In the present work we report for the first time on the preparation of biocomposites with antibacterial properties. These materials intended for bone regeneration applications are consists of a bioglass and antibacterial agent. We investigated two different bioactive glasses: 1) SiO2-CaO-MgO-P2O5-Na2O-CaF2 bioactive glass produced by conventional melt quench technique which has been successfully used in the treatment of bone defects and 2) novel bioglass compositions based on Ca- and Mg- modified silicon oxycarbide (SiCaMgOC), which exhibit an outstanding resistance against devitrification processes keeping their amorphous nature even after exposure to 1300°C. The investigated bioglass were dispersed as active phase in injectable biopolymers to improved mechanical properties. In this study we investigated two types of antibacterial agents: 1) antibacterial metals namely, Ag and Cu and 2) semiconductor nanocrystals like TiO2 and nitrogen doped TiO2 which allow optical control of antibacterial resistances. The formation of HCA on the surface of the glass was assessed by XRD and SEM while the kinetics of its biodegradation (biomineralization) was studied mainly by optical spectroscopy measurements. In addition to their promising bioactivity, the presented glasses exhibit good biocompatibility, as shown by cytotoxicity tests in the presence of various cells (mouse embryonic fibroblasts (MEF) as well as human embryonic kidney cells (HEK-293)), making them highly attractive materials for bone repair applications.
The effect of antibacterial agent insertion on the textural features and in vitro bioactive response of the resulting systems were assessed. The antibacterial properties of the materials were tested using Escherichia coli under two different irradiation energy: UV light and Vis light.