Electrochemically Deposited Polypyrrole–Glycine Coatings Incorporating Gentamicin on Magnesium Alloys: A Multifunctional Strategy for Enhanced Implant Durability and Biocompatibility

Orthopedic surgeries are often complicated by infections like osteomyelitis, challenging treatment outcomes. Traditional methods, including systemic antibiotics and surgery, are inadequate, leading to prolonged treatment and increased morbidity. Magnesium (Mg) and its composites are promising implant materials due to their biodegradability and compatibility with bone. However, their rapid degradation in physiological conditions require corrosion-resistant surface modifications. Surface coatings, such as polymeric coatings, improve the mechanical and biological properties of Mg-based implants. Additionally, drug delivery systems like gentamicin-loaded coatings offer targeted infection control and bone healing. This study explores the formation of magnesium oxide (MgO) on magnesium alloys through electrodeposition, followed by the electrochemical polymerization of polypyrrole (PPy) and glycine (Gly), with subsequent loading of gentamicin sulfate (GS) to develop multifunctional surface coatings. Characterization by AT-FTIR, XRD, FE-SEM, and EDX confirms the coatings' formation and properties. These coatings show excellent mechanical strength, corrosion resistance, antimicrobial effects, and biocompatibility. In vitro, PPy-Gly-3-coated MgO composites promote excellent osteoblast adhesion and proliferation.