RESUMEN
Magnesium shows promise as a material for temporary fixation, yet its rapid corrosion poses health risks due to metal ion release. To mitigate these concerns, a biofunctionalization approach involving dicalcium phosphate dihydrate (DCPD) compounds and Chlorella sp. biomass was employed via electrodeposition, silanization, and dip-coating. Surface characterization using XRD, FTIR, and SEM confirmed successful deposition and immobilization. Corrosion behavior was assessed through electrochemical, immersion, and atomic absorption tests, revealing improved resistance and reduced Mg2+ ion release. The coatings demonstrated significant enhancement in corrosion resistance, guarding against pitting and cracks. The findings suggest the potential of Mg/DCPD and Mg/DCPD/microalgae coatings in addressing corrosion-related risks in temporary fixation applications, promising improved biocompatibility and longevity for medical implants.
RESUMEN
Magnesium alloys have been extensively studied as degradable biomaterials for clinical applications due to their biocompatibility and mechanical properties. However, their poor corrosion resistance can lead to issues such as osteolysis and the release of gaseous hydrogen. This study investigated the influence of the activation time of magnesium surfaces in a sodium hydroxide (NaOH) solution on the concentration of active hydroxyl groups and corrosion resistance. The results indicated that immersion time significantly influences the formation of a corrosion-resistant film and the distribution of surface hydroxyl groups. Specifically, specimens treated for 7.5 h exhibited the highest concentration of hydroxyl groups and the most uniform oxide film distribution. Electrochemical tests demonstrated capacitive behavior and passive surface formation for all evaluated times, with the 7.5-h immersion in NaOH yielding superior corrosion resistance, lower current density, and a more efficient and thicker protective film. SEM and EDS analyses confirmed increased formation of Mg(OH)2 for samples treated for 5 and 7.5 h, while a 10-h treatment resulted in a brittle, porous layer prone to degradation. Statistical analysis using ANOVA and Fisher's LSD test corroborated these findings. The optimal 7.5-h alkali treatment enhanced magnesium's corrosion resistance and surface properties, making it a promising candidate for orthopedic implants. However, further studies are necessary to assess biocompatibility and physiological responses before clinical implementation.