Strontium doped poly-ε-caprolactone composite scaffolds made by reactive foaming

Bone tissue reconstruction requires materials that can stimulate growth and provide structural support. Prior research has demonstrated that strontium can influence bone metabolism by affecting intracellular pathways. It was already known that strontium acts as a dual-action agent, inhibiting resorption while promoting regeneration. However, no prior work had resolved how to integrate strontium into a scaffold with controlled porosity and mechanical stability. This gap motivated the search for a processing method that could combine strontium with a polymer scaffold. The challenge was to ensure both biocompatibility and structural integrity. Existing methods lacked the ability to simultaneously foam and chemically react materials. This paper's contribution is a novel approach to scaffold fabrication. The study builds on established knowledge of strontium’s biological effects and polymer foaming techniques.

The aim of this research was to develop a new method for creating composite scaffolds using poly-ε-caprolactone and strontium. The specific problem addressed was the need for a scaffold that supports bone growth and maintains mechanical stability. The motivation came from the limitations of current scaffolding materials in tissue engineering. Strontium’s dual action made it a candidate for inclusion in the scaffold. The researchers sought to combine strontium with a polymer using a novel foaming process. The study aimed to evaluate the resulting scaffold’s structure and biocompatibility. The goal was to produce a material suitable for in vivo applications. The novelty lay in the simultaneous foaming and chemical reaction steps.

The study used supercritical carbon dioxide to foam poly-ε-caprolactone while reacting calcium and strontium hydroxides into carbonates. The composite scaffolds were optimized for composition and strontium content. Spectroscopic techniques included infrared and Raman spectroscopy to analyze chemical structure. Energy dispersive X-ray spectroscopy confirmed elemental composition. Imaging methods like SEM and μCT were used to assess pore structure. Mechanical testing evaluated scaffold stability. In vitro biocompatibility was tested using fluorescence staining and MTT-assay. The approach combined chemical and physical processing steps to achieve the desired scaffold properties.

The composite scaffolds showed a partly open pore structure, as observed via SEM and μCT imaging. Spectroscopic analysis confirmed the presence of strontium and the expected chemical composition. Infrared and Raman spectroscopy revealed the successful formation of strontium carbonate. Mechanical testing indicated sufficient stability for potential in vivo use. The MTT-assay demonstrated good in vitro biocompatibility with cultured cells. Fluorescence staining showed cell viability and interaction with the scaffold. The strontium content was optimized to balance biological activity and scaffold integrity. The results suggest the scaffold is a promising candidate for bone tissue engineering applications.

The authors propose that the scaffold fabrication method is effective for combining strontium with poly-ε-caprolactone. The study suggests that the scaffold’s pore structure and chemistry are suitable for bone tissue engineering. The researchers observed that the scaffold’s mechanical properties are sufficient for in vivo applications. The biocompatibility results indicate that the scaffold supports cell viability and interaction. The study suggests that the dual-action properties of strontium are preserved in the composite material. The findings propose that the scaffold could be used in future in vivo experiments. The method proposed is a novel approach to scaffold fabrication. The authors suggest that further in vivo testing is needed to confirm the scaffold’s potential.