Dual-functionalized Pickering HIPE templated poly(ɛ-caprolactone) scaffold for maxillofacial implants

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Nanotechnology

Background:

• Poly (ɛ-caprolactone) (PCL) scaffolds templated by high internal phase emulsion (HIPE) are promising for bone defects but require high stabilizer concentrations and lack microenvironment considerations.
• Existing methods face challenges in industrial scalability due to high stabilizer requirements and limited focus on specific regeneration sites like alveolar bone.

Purpose of the Study:

• To develop novel nanocomposite crosslinked PCL (cPCL) scaffolds using Pickering HIPE templating with significantly reduced stabilizer concentrations.
• To functionalize these scaffolds with clove oil (CO) to impart antimicrobial properties and enhance their suitability for bone regeneration applications.
• To investigate the effect of modified silica nanoparticles (mSiNP) concentration and dispersed phase volume fraction (ϕd) on scaffold properties.

Main Methods:

• Fabrication of cPCL scaffolds via Pickering HIPE templating using modified silica nanoparticles (mSiNP) as stabilizers, with mSiNP added to the dispersed phase.
• Tuning scaffold properties by controlling mSiNP concentration (0.1–1.0 wt%) and ϕd.
• Functionalization of cPCL scaffolds with clove oil (CO) to introduce antimicrobial activity against S. aureus and E. coli.
• Evaluation of scaffold cytocompatibility using MG-63 cells to assess adhesion and proliferation.

Main Results:

• Successfully fabricated nanocomposite cPCL scaffolds using low mSiNP concentrations (0.1–1.0 wt%) via an unconventional Pickering HIPE approach.
• Achieved colloidal stability by dispersing mSiNP in silicone oil, enabling faster migration to the interface, contradicting Bancroft's rule.
• Demonstrated tuneable scaffold properties by adjusting mSiNP concentration and ϕd.
• CO-functionalized scaffolds exhibited potent eradication of S. aureus and E. coli by disrupting cellular integrity and inhibiting biofilm formation.
• CO-functionalized scaffolds showed excellent cytocompatibility, supporting MG-63 cell adhesion and proliferation.

Conclusions:

• Developed a scalable method for producing cPCL scaffolds with tuneable properties using low concentrations of Pickering stabilizers.
• Demonstrated the antimicrobial efficacy and biofilm inhibition of CO-functionalized scaffolds, addressing challenges in preventing post-operative infections.
• Confirmed the cytocompatibility of the functionalized scaffolds, highlighting their potential for promoting bone regeneration in challenging defect sites.