The Application of Polarization Microscopy in Determining Electrospinning Conditions for Preparing Drug-Loaded Nanofibers

This paper demonstrates that polarization microscopy can be a very useful tool for determining the electrospinning conditions for preparing smooth and uniform drug-loaded nanofibers. Ferulic acid (FA) was used as the model drug and PVP K60 was selected as the filament-forming matrix. Solution parameters for optimal preparation of FA-loaded PVP nanofibers were successfully established using polarization microscopy to monitor the quality of the nanofibers produced. The optimal solution parameters were: (1) 75% (v/v) ethanol as solvent, (2) the range of PVP concentration for smooth electrospinning was 10-15% (w/v), and (3) the drug concentration in the spinning solutions should not be higher than 15% (w/v) in 10% (w/v) PVP spinning solutions, in order to maintain the amophous physical state of FA in the PVP nanofiber matrix. The quality of the final FA-loaded nanofibers was confirmed using field emission scanning electron microscopy. Our research offers a simple, easy but useful optical method for determining electrospinning parameters for preparing functional nanofibers.