Wet‐Chemical Deposition of Functional Coatings for Bone Implantology

Abstract

Since the early 1980s, research on the modification of bone implant surfaces by applying coatings has mainly focused on the application of inorganic calcium phosphate (CaP) coatings using physical deposition techniques. Organic components of the extracellular bone matrix, on the other hand, play an essential role in the process of bone healing, but cannot be applied using these physical techniques. Therefore, a recent trend in biomaterials research involves development of novel wet-chemical deposition techniques for both inorganic and organic coatings. This study reviews the major wet-chemical coating techniques that are used for the deposition of inorganic CaP coatings and organic biomolecules coatings.

Functionalizing Ti-Surfaces through the EPD of Hydroxyapatite/NanoY2O3

“…The zeta potentials for both of the pure starting powders were studied as a function of pH and dispersant content by microelectrophoresis (Zeta Meter 3.0+, Zeta Meter, Inc., U.S.A.) and laser doppler velocimetry (Zetasizer Nano ZS, Malvern Instruments Ltd., U.K.) for HA particles (micrometre) and Y 2 O 3 (nanometre), respectively. For these measurements, colloidal suspensions were prepared in 10 −2 M solutions of KCl, with powder concentrations ranging from 1 to 0.1 g/cm 3 . The concentration was optimized depending on the powder and the equipment employed.…”

“…Among these, there are metallic materials currently used for surgical implants that possess good mechanical properties suitable for structural applications but have poor wear resistance; additionally, a mismatch often occurs between the nonphysiologic surface and the living tissue when these materials are used. 3 Surface modification and functionalization are proposed to address these problems and improve the performance of metal orthopedic devices. For this reason, several processing methods have been developed to provide the surface with microstructural design features that improve the durability and reliability of the metallic implants while promoting bone tissue integration.…”

“…Some of the micro structural designs include the development of porous surfaces, coating with special alloy particles, ceramics or hydroxyapatite (HA) or thermal treatment of the surfaces to reduce the grain size. 2 The appropriate use of organic or inorganic coatings on metallic surfaces makes bone formation possible at the interface between the implant surface and the surrounding tissue, 3 promoting osseo integration and improving implant integra tion. 4 Particularly, inorganic bioactive coatings prevent some problems associated with the release of potentially harmful metal ions from the metallic substrate and increase the corrosion resistance of the implant.…”

Surface Engineering for Bone Implants: A Trend from Passive to Active Surfaces

“…Organic surface modifications that are currently investigated involve immobilization of among others structural proteins, signaling molecules, enzymes or peptides onto biomaterial surfaces to target cell response at the tissue-implant interface [74,75].…”

“…Such implants cannot be coated using physical coating techniques due to their line-of-sight characteristics. In a recent review by Nijhuis et al [75], an overview is given of current trends in wet chemical deposition of biomedical coatings for bone substitution.…”