Characterization and Multi-Response Morphological Optimization for Preparation of Defect-Free Electrospun Nanofibers Using the Taguchi Method

The study presents a method on producing defect-free polyvinyl alcohol-gelatin (PVAG) nanofibers by considering multiple morphological characteristics of the produced nanofibers using the Taguchi method. Aside from minimizing the average fiber diameter, the method was also used to produce consistent, monodispersed PVAG nanofibers without the usual defects of beading and splattering. The experiments are performed considering the effect of polymer composition (PVAG ratio and solvent ratio of water, formic acid, and acetic acid H₂O:FA:HAc) and process factors (tip-to-collector distance TCD and solution flow rate) on fiber morphology. Fiber morphology is measured in terms of 4 responses: average fiber diameter, standard deviation of fiber diameter, occurrence of beading, and occurrence of splattering. Results show that maximum overall desirability for electrospinning PVAG nanofibers at smallest average diameter and deviation (26.10 ± 9.88 nm) with chance of moderate beading and zero splattering is predicted at PVAG mass ratio of 6.5:3.5, H₂O:FA:HAc solvent volume ratio of 4:4:2, TCD of 12.5 cm, and flow rate of 1 ml h^-1. Results of confirmatory run agree with the predicted factor levels at maximum desirability, with average fiber diameter and standard deviation measured to be 26.95 ± 6.39 nm. PVAG nanofibers of the confirmatory run are also both bead-and splatter-free. Results suggest the application of Taguchi method can offer a robust and rapid approach in deriving the conditions for production of new and high-quality PVAG nanofibers for tissue engineering scaffolds.