Researchers at Texas A&M University, College Station, report that they have developed a shape memory polymer scaffold that exhibits an open porous structure and has the capacity to conformally self-fit into irregular defects. The material fill gaps in bone, while promoting bone growth. The S scaffold was prepared via photocrosslinking of poly(-caprolactone) (PCL) diacrylate using a SCPL method, which included a fused salt template.
A bioactive polydopamine coating was applied to coat the pore walls. Following exposure to warm saline at T > Ttrans (Ttrans = Tm of PCL), the scaffold became malleable and could be pressed into an irregular model defect. Cooling caused the scaffold to lock in its temporary shape within the defect.
The research by Texas A&M Department of Biomedical Engineering associate professor Melissa Grunlan is detailed in the scientific journal Acta Biomaterialia. Working with colleagues at Texas A&M and Rensselaer Polytechnic Institute, Dr. Grunlan has created a polymer foam that is malleable after treating with warm saline, allowing it to precisely fill a bone defect before hardening into a porous, sponge-like scaffold that promotes new bone formation.
The researchers note that while tissue engineering is a promising alternative for treating critical-sized cranio-maxillofacial bone defects, improvements in scaffold design are needed — in particular, scaffolds that can precisely match the irregular boundaries of bone defects as well as exhibit an interconnected pore morphology and bioactivity would enhance tissue regeneration.
Prof. Grunlan is also head of the Silicon-Containing Polymeric Biomaterials Group ). A principal distinction of this research is the development of inorganic silicon-containing polymeric materials and their combination with organic polymers to obtain inorganic-organic hybrid materials with unique properties. Several specific research areas include: clot-resistant coatings for blood-contacting devices, self-cleaning membranes for implanted biosensors, and the scaffolds for tissue engineering and shape memory polymers (SMPs) for bone healing.
