Preparation of interconnected highly porous polymeric structures by a replication and freeze-drying process

Area of Science:

• Materials Science
• Biomaterials Engineering
• Polymer Chemistry

Background:

• Developing 3D porous polymeric scaffolds with high porosity and interconnected pores is crucial for tissue engineering and regenerative medicine.
• Existing methods often struggle to achieve both high porosity and robust pore interconnectivity simultaneously.

Purpose of the Study:

• To develop a novel fabrication technique for creating highly porous (93-98%) and well-interconnected 3D degradable polymeric scaffolds.
• To investigate the influence of fabrication parameters on scaffold architecture and mechanical properties.

Main Methods:

• Utilized a freeze-drying technique combined with a leachable template (sugar or salt) to create pore networks.
• Polymer solutions (5-15% w/v) in 1,4-dioxane of poly(D,L-lactide) (PDLLA), 1000PEOT70PBT30, and poly(epsilon-caprolactone) (PCL) were employed.
• Leaching the template created interconnected pores, while freeze-drying contributed to overall porosity.

Main Results:

• Achieved high porosities ranging from 93-98% with excellent pore interconnectivity, surpassing traditional methods.
• Scaffold architecture featured large, template-defined pores and smaller freeze-dried pores.
• Compression moduli varied from 13.0 to 301.5 kPa, depending on polymer type, porosity, and freezing temperature.

Conclusions:

• The combined freeze-drying and leachable template method effectively produces highly porous, interconnected 3D polymeric scaffolds.
• This technique offers tunable mechanical properties and is suitable for various biomedical polymers.
• The resulting scaffolds hold significant promise for applications in tissue engineering and drug delivery.