Biocompatible and Antibacterial PCL-TiO₂@Ag/γ-CD MOF Nanocomposite Coating for Corrosion Resistance of Magnesium Alloy in Simulated Body Fluid

Abstract

Magnesium alloys are promising candidates for bio-implant applications due to their biodegradability and biocompatibility. However, their rapid corrosion remains a critical limitation. This study presents the development of a multifunctional nanocomposite coating designed to enhance the corrosion resistance and antibacterial properties of magnesium alloy implants. The coating comprised γ-cyclodextrin metal-organic frameworks (γ-CD MOFs) decorated with TiO₂@Ag core-shell nanoparticles, embedded in a polycaprolactone (PCL) matrix. Immersion tests in a simulated body fluid (SBF) revealed an initially higher corrosion rate for the PCL-TiO₂@Ag/γ-CD MOF coating compared to the coating without TiO₂@Ag nanoparticles; however, it demonstrated significant improvement over time. After five days, the corrosion inhibition reached 95.44%, with the corrosion rate decreasing to 1.70 mpy. Additionally, the composite coating exhibited strong antibacterial activity against Escherichia coli, Pseudomonas, and Staphylococcus aureus. Furthermore, MTT assays indicated that the coating facilitated the growth and proliferation of osteoblast-like MC3T3-E1 cells, confirming its nontoxicity and biocompatibility. These findings highlight the potential of the PCL-TiO₂@Ag/γ-CD MOF nanocomposite as a biocompatible, antibacterial, and corrosion-resistant coating for biodegradable magnesium implants, offering a promising solution for biomedical applications.

Keywords

Antibacterial coating / Biocompatible / Anti-corrosion coating / γ-CD metal-organic framework / TiO₂@Ag core shell

Conflict of Interests

The authors affirm that they do not have any known competing financial interests or personal relationships that could have influenced the work presented in this paper.

Acknowledgments

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Author Contributions

Sara Dehghan-Chenar: Writing - original draft, Investigation, Data curation, Validation, Conceptualization, Formal analysis, Software.

Hamid R. Zare: Supervision, Writing - review & editing

Zahra Mohammadpour: Assistance in result interpretation, review & editing

Maryam Sadat Mirbagheri-Firoozabad performed the antibacterial tests.

Data Availability

The data supporting the findings of this study can be obtained from the corresponding author upon a reasonable request.

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