Fabrication of biomedical composite coatings by electrophoretic deposition and dip coating methods

Abstract

It is essential to develop a new type of nanocomposite biomedical implant coatings that consist of bioactive ceramics and polymers, as well as customized surface characteristics. These coatings play a vital role in enhancing cell adhesion, proliferation, and interlocking at the interface between bone tissue and the implant. This development is crucial for prolonging the durability of orthopaedic implants. The utilization of combined colloidal and electrochemical processing techniques, specifically EPD and dip coating, enables the fabrication of these novel multi-component materials with relative simplicity. Additionally, they can be utilized to create nanostructures and surface topography that imitate the composition of human skeletal tissue on a nanoscale level. In addition, colloidal-electrochemical processing techniques can be easily scaled up for clinical product development and mass manufacture, unlike many regularly utilized nanotechnology processing techniques. The absence of efficient and biocompatible dispersants and extractors is a significant obstacle to the widespread use of colloidal-electrochemical methods for fabricating novel biomaterials in EPD, as the success of this process relies on the utilization of a stable colloidal precursor. Biomimetics, sometimes known as gaining inspiration from the natural world, is one way to generating effective dispersion and extracting agents. Using this methodology, we identified novel extracting agents. These agents proved to be highly effective in extracting particles and forming composite films that combined organic and inorganic components, containing different sized of silica particles and polyvinylidene fluoride (PVDF). By extending the method, biomimetic inspiration was derived from the human digestive system, to use bile acid salts (BAS) as solubilizing, charging, dispersing and film-forming agents for the preparation of composite coatings, containing water insoluble drugs and proteins. These coatings have the potential to be utilized for targeted administration of antibiotics, thereby preventing surgical infections after implantation. Furthermore, the inclusion of BAS surfactants enables the solubilization and dispersion of hydrophobic drugs and molecules, as well as the creation of composite films with functional properties using EPD. Moreover, a novel technique is devised for the anodic EPD of alginic acid polymer (AlgH) and composite films that contain drug molecules within the AlgH matrix. This approach entailed utilizing L-arginine as an alkalizing agent to enhance the solubility of medicines that have low solubility in water. AlgH and medication molecules are dissolved in water and then deposited via anodic EPD. Dip coating remains a challenging task when it comes to depositing high concentrations of non-toxic solvents containing high molecular weight (MW) polymers, such as poly(ethyl methacrylate) (PEMA) and poly(methyl methacrylate) (PMMA). In this study, we initially suggested the utilization of water-isopropanol as a co-solvent for dissolving high molecular weight PMMA at high concentrations. Additionally, we utilized an advanced dispersion agent to facilitate the solubilization of PEMA. It was discovered that water molecules can surround and solvate the carbonyl groups of the polymers. This technology avoided the use of noxious solvents and a protracted heating process for their elimination. In addition, these coatings have the potential to be integrated with advanced inorganic particles, such as drugs, diamond and HA, for use in biomedical applications.