Quantifying Mechanical Properties of PCL-Based Nanofiber Mats Using Atomic Force Microscopy

Abstract Polymeric scaffolds aid in creating an environment for cell proliferation and differentiation in tissue engineering applications by acting as temporary artificial extracellular matrices (ECMs) for cells to form functional tissue. Many studies have reported that cell behavior can be significantly affected by the physical and chemical properties of a given scaffold. Therefore, the mechanical and structural properties of these scaffolds must be characterized. Polymeric solutions, such as polycaprolactone (PCL), have been electrospun into nanofiber mats to be used as cell scaffolds. Polycaprolactone (PCL) is a biocompatible polymer and is commonly used in tissue engineering applications; however, PCL is hydrophobic, which makes it difficult for cells to adhere to the mat. Coating the PCL-based mats with collagen, a naturally occurring protein with hydrophilic properties, may improve cell adhesion to the scaffold. The collagen coating may also alter the mechanical properties of the nanofiber mats. In this study, the effect of collagen coating on cell adhesion and proliferation are investigated using alamarBlue tests. Additionally, the mechanical and surface properties of PCL-based nanofiber mats are investigated using a Nanosurf C3000 atomic force microscope (AFM). One batch of PCL mats were coated with collagen, while the uncoated mats were used as controls. The cell behavior and material property values obtained from the uncoated PCL and collagen-coated PCL mats were analyzed and compared. The results of this study suggest that collagen does significantly influence the cell proliferation and material properties of PCL-based mats and that further studies should be conducted to better understand the effects of the nanoscale properties of the PCL-based mats on cell adhesion.