Deposition and characterization of hybrid nanocomposite films for orthopaedic applications

We are currently synthesizing hybrid bioactive inorganic/organic nanocomposites and studying the heteromixing of these materials.  These systems are being investigated as artificial interfaces for metallic surgical implants.  Coating these surfaces with bioactive composite films can promote bone growth, deliver targeted antibiotics to the defect site, and prevent corrosion of the metallic implant.  The nanocomposites were composed of the following materials: chitosan (a fibrous polymer with antibiotic properties), hydroxyapatite (the naturally occurring inorganic component of bone), and Laponite (a bioactive clay that encourages bone growth and bone cell proliferation about its interface). Various binary composites were synthesized through solution-based methods such as sol-gel casting and electrophoretic deposition.  The morphology, composition and crystallinity of the films self-assembled on varied substrates (stainless steel, aluminum, and titanium) were characterized using atomic force microscopy (AFM), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and powder X-ray diffraction (XRD).  This research has provided insight on tuning the heterointerfaces and interstitial architectures of these hybrid nanocomposites to aid in the synthesis and engineering of these systems to enhance orthopaedic performance.