OPTIMIZATION OF ELECTROSPINNING PROCESS PARAMETERS FOR TISSUE ENGINEERING SCAFFOLDS

Abstract

The goal of the current study was to optimize important process parameters for electrospinning polycaprolactone (PCL) for growing 3T3 fibroblasts. We hypothesized that the smallest obtainable fiber diameter would provide the best cell growth kinetics and we tested this hypothesis for three different process parameters: solution concentration, voltage and collector screen distance. Beaded structures were formed when using low concentration electrospinning solutions (8 wt% to 13 wt%), in which the viscosity ranged from 16.0 c P to 340.0 c P . In this concentration range, cell growth kinetics was impeded when using a high concentration of cells (8–10 × 105). Higher PCL concentration led to an increase in the average fiber diameter from 400 nm to 1600 nm when PCL solution concentration changed from 15 wt% to 20 wt%. Although, the mean values indicated that cell growth kinetics were higher at the lower end of the concentration (15% as opposed to 20%) and this correlated with lower average fiber diameter, the results in this range were not statistically significant (p > 0.05). The average fiber diameter of scaffolds first decreased and then increased when electrospinning voltage was increased. The cell growth kinetics demonstrated that smaller average diameter PCL fiber scaffolds had higher growth kinetics than larger average diameter scaffolds with the best conditions obtained at 15 KV. By increasing the screen distance, the average fiber diameter decreased but had no significant impact on cell growth kinetics. In summary, the optimal parametric space for 3T3 fibroblast growth for our studies was electrospinning a 15 wt% PCL solution using 15 kV voltage and a 25 cm collector distance.