Modeling the density gradient of 3D nanofiber scaffolds fabricated by divergence electrospinning

Following recent insights on structure-cell-function interactions and the critical role of the extracellular matrix (ECM), the latest biofabrication approaches have increasingly focused on designing materials with biomimetic microarchitecture. Divergence electrospinning is a novel fabrication method for three-dimensional (3D) nanofiber scaffolds. It is introduced to produce 3D nanofiber mats that have numerous applications in regenerative medicine and tissue engineering. One of the most important characteristics of 3D nanofiber mats is the density gradient. This study provides a statistical analysis and response surface modeling framework based on experimental data to evaluate the manner by which the geometric designs of double-bevel collectors influence the fiber density gradient. Specifically, variance of analysis and sensitivity analysis were performed to identify parameters that had significant effects, and a response surface model embedded with seven location indicators was developed to predict the spatial distribution of fiber density for different collector designs. It was concluded that the collector height, bevel angle, and their interactions were significant factors influencing the density gradient. This study revealed the sensitivity of system configuration and provided an optimization tool for process controllability of microstructure gradients.