Fabrication of Reinforced Polycaprolactone and Cellulose Nanocrystal Composite Membranes for Cardiovascular Tissue Engineering Applications

Cardiovascular disease is the leading cause of death worldwide each year. Modern medical treatments for myocardial infarctions primarily consist of stents or blood thinners and are aimed at restoring oxygen flow to the heart. However, these treatments do not address the scar tissue that forms as a result of cardiac events, thus leaving patients at a greater risk for repeat events. Cell scaffolding is a prominent technology in tissue engineering that utilizes biomimetic materials to facilitate native tissue regrowth. Polycaprolactone (PCL) is a synthetic biopolymer that has successfully been used in bone and musculoskeletal tissue engineering in the past. However, PCL is limited for cardiovascular cell scaffolds because of its low mechanical strength and poor cell affinity. Cellulose nanocrystals (CNCs), naturally occurring subunits of cellulose, have a high tensile strength and tunable surface chemistry rich in hydroxyl groups. These unique properties make CNCs ideal candidates as additive materials for PCL-based cell scaffolds. In this research, the preparation of uniformly mixed PCL and CNC composite materials at different ratios was utilized to make membranes. Mechanical properties, including tensile strength, Young’s modulus, and elongation strain, were characterized. It was found that an increasing concentration of CNCs in the composites led to increasing mechanical strength values of the membranes, demonstrating the practicality of PCL/CNC composite materials for tissue engineering applications in stress-intensive environments like the cardiovascular system.