PCL-coated hydroxyapatite scaffold derived from cuttlefish bone: morphology, mechanical properties and bioactivity

Bone tissue engineering requires scaffolds that mimic natural bone structure while supporting cell growth and mineralization. Traditional scaffolds often lack sufficient mechanical strength or fail to maintain porosity. Prior research has shown that hydroxyapatite (HAp) scaffolds derived from natural sources like cuttlefish bone can retain complex architectures. However, these scaffolds may exhibit limited mechanical performance. This gap motivated the exploration of composite materials that combine HAp with biodegradable polymers. No prior work had resolved how to effectively coat HAp scaffolds with poly(ε-caprolactone) (PCL) while preserving porosity. The need for a scaffold that supports both mechanical function and bioactivity remains unmet. This study addresses the challenge of enhancing scaffold properties without compromising structural integrity. The findings aim to advance scaffold design for clinical applications.

This study aimed to develop a composite scaffold by coating hydroxyapatite derived from cuttlefish bone with poly(ε-caprolactone). The primary goal was to improve mechanical properties while maintaining the scaffold’s porous structure. The motivation came from the need for materials that support tissue growth and vascularization. The researchers focused on preserving the original architecture of cuttlefish bone during hydrothermal transformation. A secondary objective was to assess the bioactivity of the resulting scaffold. The study also sought to evaluate compressive strength and elastic modulus. The authors aimed to determine if the composite scaffold could meet the mechanical requirements of trabecular bone. The ultimate purpose was to identify a promising material for bone tissue engineering.

The study involved hydrothermal transformation of cuttlefish bone at 200°C to produce hydroxyapatite scaffolds. The scaffolds were then coated with poly(ε-caprolactone) using vacuum impregnation. X-ray diffraction was used to analyze the crystalline structure of the scaffolds. Fourier transform infrared spectroscopy confirmed the presence of PCL and HAp. Thermogravimetric analysis assessed thermal stability. Scanning electron microscopy with energy dispersive X-ray analysis provided morphological data. Bioactivity was tested by immersing scaffolds in Hank’s balanced salt solution. Mechanical properties were measured under compression to evaluate strength and elasticity.

The PCL-coated hydroxyapatite scaffold retained the original interconnected porous structure of cuttlefish bone. The compressive strength measured 0.88 MPa, and the elastic modulus was 15.5 MPa. These values fall within the lower range of human trabecular bone properties. The scaffold exhibited in vitro mineralization of calcium phosphate on its surface. Both pure HAp and HAp/PCL scaffolds showed formation of bone-like apatite. The PCL coating improved mechanical performance without blocking porosity. The composite scaffold demonstrated enhanced stability and bioactivity. The results suggest the material is suitable for bone tissue engineering applications.

The authors propose that the PCL-coated hydroxyapatite scaffold is a viable option for bone tissue engineering. The scaffold maintains the original architecture of cuttlefish bone, which is essential for tissue growth. The mechanical properties of the composite material align with those of trabecular bone. The presence of bone-like apatite on the scaffold surface supports its bioactivity. The PCL coating enhances mechanical performance without compromising porosity. The study confirms that the scaffold supports mineralization in vitro. The findings suggest the material could be used in clinical settings where structural and functional support is needed. The authors conclude that the scaffold meets the criteria for tissue engineering applications.