Drug release behavior of electrospun twisted yarns as implantable medical devices

Abstract

In this study, twisted drug-loaded poly(L-lactide) (PLLA) and hybrid poly(L-lactide)/poly(vinyl alcohol) (PLLA/PVA) yarns were produced using an electrospinning technique based on two oppositely charged nozzles. Cefazolin, an antibiotic drug was incorporated in the yarn fibers by addition to the PLLA electrospinning solution. Morphological studies showed that independent of the twist rate, uniform and smooth fibers were formed. The diameter of the electrospun fibers in the yarns decreased at higher twist rates but produced yarns with larger diameters. At increasing twist rates the crystallinity of the fibers in the yarns increased. In the presence of cefazolin the fiber diameter, yarn diameter and crystallinity were always lower than in the non-drug loaded yarns. In addition the yarn mechanical properties revealed a slightly lower strength, modulus and elongation at break upon drug loading. The effect of the twist rate on the cefazolin in vitro release behavior from both PLLA and hybrid yarns revealed similar profiles for both types of drug-loaded yarns. However, the total amount of drug released from the hybrid PLLA/PVA yarns was significantly higher. The release kinetics over a period of 30 d were fitted to different mathematical models. Cefazolin release from electrospun PLLA yarns was governed by a diffusion mechanism and could best be fitted by Peppas and Higuchi models. The models that were found best to describe the drug release mechanism from the hybrid PLLA/PVA yarns were a first-order model and the Higuchi model.

Morphological and mechanical properties of drawn poly(l‐lactide) electrospun twisted yarns

“…In this work, to produce continuous twisted yarns, an electrospinning setup consisting of two oppositely charged nozzles was used. The fibers could be assembled into fibrous yarns using a device consisting of a take‐up roller and twister .…”

“…Because twist can compress the bundle and increase adhesion between fibers and thus lateral interactions and frictional forces between the fibers within the yarn structure. Moreover, twist improves the bundle uniformity [13,16,18].…”

Bio-Based Electrospun Fibers for Wound Healing

“…Electrospun fibers can deliver agents to the target sites, while reducing the toxic side effects of drugs. Electrospun drug carriers improve the effectuality of drug therapy by controlling the rate, and mechanism of release [58,[68][69][70]. Especially, the stimuli-responsive drug delivery systems are promising materials for generating smart wound dressings.…”

“…Electrospun fibers demonstrate many advantages for the delivery of biomolecules for healthcare. Owing to the small diameter and large surface area to volume ratio, electrospun fibers grant good drug encapsulation efficiency and result in controllable drug delivery to the on-demand sites [58,68,79]. Furthermore, electrospinning affords various choices by altering the morphology, diameter, porosity, and alignment of fibers by controlling the operational variables and type of materials.…”

“…Furthermore, electrospinning affords various choices by altering the morphology, diameter, porosity, and alignment of fibers by controlling the operational variables and type of materials. Tuning these features, provides modulation of drug release behavior and its kinetics [58,68,80]. For example, it has been reported that the drug-loaded dressings composed of fibers with a smaller diameter and higher surface area showed faster release.…”