ABSTRACT
The employment of electrospun polymeric nanofibers as drug delivery vehicles has been based on their unique functionality and inherent nanoscale morphological characteristics. In addition, due to the flexibility during processing with a variety of structural architectures containing drug molecules, these could be fabricated from monolithic nanofibers to various multiple composition systems. These important benefits allow finely tuned drug-eluting profiles that rely on controlling drug travelling length or modulating the affinity between matrix materials and drugs. In this entry, physical and chemical immobilization methods of bioactive molecules on the surface of various polymeric nanofibers with their applications to drug delivery are described, and various electrospun nanofibers made of poly(ε-caprolactone) (PCL)/hydroxyapatite (HAp), polystyrene (PS), and silk fibroin with improved cell adhesion and proliferation are reviewed. Electrospun nanofibers composed of poly(glycolic acid) (PGA), poly(L-lactic acid) (PLLA), or poly(lactic-co-glycolic acid) (PLGA) were modified with carboxylic acid groups through plasma glow discharge with oxygen and gas-phased acrylic acid. Such hydrophilized nanofibers were shown to enhance fibroblast adhesion and proliferation properties. Drug release mechanism is associated with polymer degradation and complicated diffusion pathway along nano-void spaces within nanofiber mesh. Hollow nanofibrous tubes by coaxial electrospinning also have provided a promising structure for the encapsulation of target drug molecules. This approach succeeded in achieving high drug loading and also facilitation of the solubilization of some insoluble and intractable drugs.
