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8
Systematic Development of Electrospun PLA/PCL Fiber
Hybrid Mats: Preparation, Material Characterization, and
Application in Drug Delivery
Hazim J. Haroosh and Yu Dong

8.1
Introduction

Electrospinning is a cutting-edge integrated processing technique, which specifi-
cally combines electrospraying with spinning [1]. It has become the topic of inter-
est with increasing research concerns in the last decade owing to the advent of
nanotechnology and nanomaterials. This approach has shown numerous merits
over conventional polymer processing methods, comprising relatively high fab-
rication rate, cost effectiveness, potential capability to create small fibers with
large surface areas [2–5], and applicability to numerous types of polymers [6].
In particular, electrospinning is regarded as a functional, comfortable, and flex-
ible process to successfully produce continuous ultrafine fibers with diameters
ranging from nanometers to microns [7–9]. Fiber length in thousands of kilo-
meters can be achieved over a short period of time [10]. This technique is rea-
sonably uncomplicated, adaptable, quick, and functional, resulting in amenable
morphologies and greater mechanical properties of fabricated fiber mats [11, 12].
Nanofiber mats especially have potential biomedical uses such as sutures, car-
diac grafts, wound dressings, artificial blood vessels [13], nerve guidance conduits,
bone renewal materials, vascular grafts [14], tissue scaffolds, implants, and control
systems for drug delivery [15–17]. Their advantages in the fields of tissue scaffolds
and drug delivery are of great interest, which include the accomplishment of a high
level of drug capacities, relatively simple drug entrapment, steadiness and protec-
tion of loaded drug, control of drug burst, high surface area leading to enhanced
drug release, and particular morphologies that can be managed through manufac-
ture [18–20]. In addition to these, side effects of drugs can diminish along with
their increased bioavailability. As far as the drug delivery systems are concerned,
nanofibers can allow for site-specific drug delivery in the body, and furthermore,
more than one drug can be directly encapsulated into the nanofibers [21].
The fundamental setup of electrospinning comprises four major components,
namely, a high-voltage power supply, a syringe pump, a spinneret, and a grounded
mesh collector (or a rotating mandrel) [22–24]. The well-known Taylor cone is
usually generated in electrospinning with the assistance of an external electrical

Biodegradable Polyesters, First Edition. Edited by Stoyko Fakirov.
© 2015 Wiley-VCH Verlag GmbH & Co. KGaA. Published 2015 by Wiley-VCH Verlag GmbH & Co. KGaA.