An Extracellular Matrix-like Surface for Zn Alloy to Enhance Bone Regeneration

Abstract

Zn-based alloys are promising biodegradable implants for bone defect repair due to their good mechanical performance and degradability. However, local Zn2+ released from Zn-based implants can seriously affect adhering cell behaviors as well as new bone formation on implant surfaces. To address this issue, we have fabricated a bone-mimetic extracellular matrix (ECM)-like surface on Zn-1Ca implants using a hybrid process of anodization, hydrothermal treatment (HT), and fluorous-curing. The ECM-like surface consisted of Zn2SiO4 nanorods layered with collagen I (Col-I). The Zn2SiO4 nanorods were hemicrystallized and transformed by the reaction of Zn­(OH)2 and SiO4 4– during the HT. The Zn2SiO4 nanorods effectively protected the substrate from corrosion; the Col-I layer decreased the degradation of Zn2SiO4 nanorods and further reduced Zn2+ release into the medium. This ECM-like surface generated a microenvironment with appropriate Zn2+ levels, nanorod-like topography, and Col-I. It significantly improved adhesion, proliferation, and differentiation of osteoblasts on implant surfaces and vascularization of endothelial cells in the extract medium. The in vivo results are in good agreement with in vitro tests, with the ECM-like surface significantly enhancing new bone formation and bone-implant contact compared to the bare implant surface. Overall, this bone-mimetic ECM-like material of Col-I layered Zn2SiO4 nanorods is a promising scaffold that promotes the bone regeneration of Zn-based implants.

Fabrication of a Nanoscale Magnesium/Copper Metal–Organic Framework on Zn-Based Guided Bone Generation Membranes for Enhancing Osteogenesis, Angiogenesis, and Bacteriostasis Properties

“…The formation of ZnO may be mainly due to the corrosion of the Zn matrix during the hydrothermal procedure. 34 Figure 2f displays the FTIR patterns of various Mg/Cu-MOF coatings on the pure Zn surface. The presence of a broad peak at ∼3446 cm −1 can be attributed to the O−H stretching of hydroxyl groups in the organic ligand DHTA, the methanol solvent, and the absorbed water molecules on the sample surface or in the channels of MOF-74.…”

“…36-1451) can also be discovered, the intensities of which are higher for bimetallic coatings than for Mg-MOF coating. The formation of ZnO may be mainly due to the corrosion of the Zn matrix during the hydrothermal procedure Figure f displays the FTIR patterns of various Mg/Cu-MOF coatings on the pure Zn surface.…”

Metallic Materials for Bone Repair

“…Although Zn alloys have a moderate degradation rate compared to Fe and Mg alloys, their low strength and low elastic modulus restrict their application as bone implants for bone repair. [15,83] Zn alloys with various properties have been explored through the addition of various alloying elements. [35] Therefore, Zn alloys are considered promising biodegradable metals for bone repair.…”

Biodegradable Implants for Internal Fixation of Fractures and Accelerated Bone Regeneration

“…In addition, Zn-based implants are also a promising biodegradable material with great biocompatibility and functionality. − Zn-based implants can release zinc ions for affecting cell adhesion and promoting new bone formation . Unfortunately, the yield strength and elongation of pure Zn alloy is extremely low, and thereby Zn-based alloys were integrated with other elements for better mechanical performance .…”