Heat's Role in Solution Electrospinning: A Novel Approach to Nanofiber Structure Optimization.

In this study, we explored an innovative application of heat-assisted solution electrospinning, a technique that significantly advances the control of phase separation in polystyrene (PS) fibers. Our experimental approach involved the use of direct heating and a convection air sheath applied through a coaxial needle, focusing on solvents with varying vapor pressures. This method enabled a detailed investigation into how solvent evaporation rates affect the morphology of the electrospun fibers. SEM and AFM measurements revealed that the application of direct heating and a heated air sheath offered precise control over the fiber morphology, significantly influencing both the surface and internal structure of the fibers. Additionally, we observed notable changes in fiber diameter, indicating that heat-assisted electrospinning can be effectively utilized to tailor fiber dimensions according to specific application requirements. Moreover, our research demonstrated the critical role of solvent properties, particularly vapor pressure, in determining the final characteristics of the electrospun fibers. By comparing fibers produced with different solvents, we gained insights into the complex interplay between solvent dynamics and heat application in fiber formation. The implications of these findings are far-reaching, offering new possibilities for the fabrication of nanofibers with customized properties. Furthermore, this could have profound impacts on various applications, from biomedical to environmental, where specific fiber characteristics are crucial. This study not only contributes to the understanding of phase separation in electrospinning but also opens avenues for further research on the optimization of fiber properties for diverse industrial and scientific applications.

Exploring temperature-responsive drug delivery with biocompatible fatty acids as phase change materials in ethyl cellulose nanofibers.

This study introduces a novel temperature-responsive drug delivery system using ethyl cellulose (EC) nanofibers encapsulating a eutectic mixture of lauric acid/stearic acid (LA/SA) as phase change materials (PCMs) and Rhodamine B (RhB) as a model drug. Employing blend electrospinning, the nanofibers achieved controlled drug release responsive to temperature changes. The peak shift of the carbonyl group in FTIR analysis confirmed drug-polymer compatibility, while the absence of RhB peaks in the XRD and DSC assessments revealed RhB's amorphous distribution within the fibers. Our findings demonstrate that RhB release is dependent on its loading, with a slow initial release (<2 %) for 1 % and 5 % RhB loadings and a burst release (~12 %) for 10 % loading. Notably, the release rate was tunable at 37 °C by adjusting LA/SA concentration. The optimal LA/SA loading for temperature-responsive release is identified as 10 %. Over 240 h, there is a 32 % increase in RhB release at 37 °C, and an additional 8 % increase at 40 °C, compared to 25 °C. This research illustrates the potential of PCM-integrated nanofibers in smart drug delivery, particularly for chemotherapy, antibiotics, and anti-inflammatory drugs, showcasing an innovative approach to improving therapeutic efficiency while reducing side effects.