Development of bioactive nanocomposite membranes with MgO nanoparticles for bone regeneration

Abstract

Introduction

Bone fractures pose a challenge to healthcare systems due to both their high incidence and clinical complexity, which varies depending on multiple factors. Open fractures in particular represent a major clinical challenge due to their complexity and the need for devices that allow proper bone tissue fixation. However, these devices are inert and do not promote bone regeneration.
To address this, the development of biofunctional materials capable of generating osteogenic and osteoinductive stimuli has been explored.

Objective

To develop bioactive membranes capable of promoting bone regeneration by generating a physiologically favorable microenvironment for cell differentiation and bone tissue formation.

Methodology

Membranes were fabricated via electrospinning using polycaprolactone and type B gelatin, and functionalized with different concentrations of magnesium oxide nanoparticles, resulting in three-dimensional structures. The samples were characterized by scanning electron microscopy, biodegradation assays, wettability, water contact angle measurements, Fourier-transform infrared spectroscopy, and magnesium ion release analysis.
Mesenchymal stem cells and osteoblasts were seeded and cultured to evaluate the biological response. Cell viability and metabolic activity were assessed using MTT-formazan and Calcein-AM/Ethidium homodimer assays. Additionally, cell differentiation was evaluated over 14 days of culture, analyzing calcium deposit formation through both quantitative and qualitative alizarin red staining.

Results

The results suggest the formation of multifibrillar structures resembling the extracellular matrix, with fiber distribution and pore size adequate to support cell interaction. The samples exhibited a degradation time compatible with bone regeneration and primary callus formation, attributed to the physicochemical properties of the material.
Water contact angle measurements indicated favorable hydrophilicity for interaction with biological environments, attributed to the functional groups provided by type B gelatin.
Fourier-transform infrared spectroscopy confirmed the appropriate integration of components, with no evidence of secondary chemical group formation. Magnesium ion release showed a gradual profile, positively correlated with degradation time and within ranges considered safe and osteoinductive according to the literature.
Cell viability and metabolic assays indicated low cytotoxicity with appropriate metabolic activity levels, especially in membranes with higher nanoparticle concentrations. Finally, osteogenic differentiation assays showed increased calcium deposit formation in cells cultured on membranes with higher MgO concentrations, suggesting a positive effect on osteoblastic differentiation induction.

Conclusion

The developed membranes exhibited favorable structural, physicochemical, and biological properties for bone regeneration applications, highlighting their biocompatibility, magnesium ion release profile, , and osteoinductive capacity. These results support their potential as an adjuvant in bone repair therapies and justify their evaluation in preclinical models.