Surfactant Interactions and Solvent Phase Solubility Modulate Small
Molecule Release from Emulsion Electrospun Fibers
Abstract
Emulsion electrospinning represents a tunable system for the fabrication
of porous scaffolds for controlled, localized drug delivery in tissue
engineering applications. This study aimed to elucidate the role of
model drug interactions with emulsion chemistry on loading and release
rates from fibers with controlled fiber diameter and fiber volume
fraction. Nile Red and Rhodamine B were used as model drugs and
encapsulation efficiency and release rates were determined from
poly(caprolactone) (PCL) electrospun fibers spun either with no
surfactant (Span 80), surfactant, or water-in-oil emulsions. Drug
loading efficiency and release rates were modulated by both surfactant
and aqueous internal phase in the emulsions as a function of drug
molecule hydrophobicity. Overall, these results demonstrate the role of
intermolecular interactions and drug phase solubility on the release
from emulsion electrospun fibers and highlight the need to independently
control these parameters when designing fibers for use as tunable drug
delivery systems.