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276 11 Electrospun Biopolymer Nanofibers and Their Composites for Drug Delivery Applications

from electrospun nanofibers can be finely tuned by controlling the crystallinity,
glass transition temperature (T ) of the polymer, and hydrophilicity or hydropho-
g
bicity of the drug, as well as the binding affinity between the drug and polymer
matrix [11–13].
Electrospinning affords great flexibility in selecting materials for drug delivery
applications; either biodegradable or nondegradable materials can be used to
control drug release via diffusion alone or diffusion and scaffold degradation.
In addition, a number of drugs can be delivered owing to the flexibility in
material selection, including antibiotics, anticancer drugs, proteins, and DNA.
Combined with various electrospinning techniques, a variety of different drug
loading methods can be utilized to give finer control over drug release kinetics,
such as embedded drugs, coatings, and encapsulated drugs (e.g., coaxial and
emulsion electrospinning). Therefore, this chapter concerns the recent progress
in drug delivery systems of electrospun drug/biopolymer composites with simply
blended or uniquely encapsulated structures, which can be achieved by conven-
tional electrospinning of drug/biopolymers or nanoparticle/biopolymer blends,
core–shell (coaxial and emulsion) electrospinning, or electrospraying method.
Moreover, selected biomedical applications of the aforementioned electrospun
drug/biopolymer composites will be broadly presented with controlled release
properties, such as wound dressings, devices, and scaffolds for localized delivery
of chemotherapeutics.

11.2
Simply Blended Drug/Biopolymer Nanofibers by Conventional Electrospinning for
Drug Delivery

Electrospinning was first applied for patents by Formhals [14] in 1934, where an
experimental setup for generating polymer filaments was introduced. Figure 11.1
shows a schematic illustration of the basic setup for electrospinning, which con-
sists of three major modules: a high-voltage power generator, a syringe pump
(syringe included), and a collector [15]. Polymer solution hosted in the syringe

Electrospinning High voltage power supply

Nanofibers
15 kV
Syringe pump

Collector
Polymer solution
Figure 11.1 Schematic illustration of the basic electrospinning setup. (Reproduced with
permission from Ref. [15]; Copyright 2012 American Chemical Society.)