Design of vascular prostheses by melt electrospinning—structural characterizations

Abstract

The general objective of this research is to use melt electrospinning to design and fabricate semibiodegradable and multilayered fibrous structures that have potential applications for cardiovascular implants, including small-diameter (<6 mm) blood vessels replacements. In the first stage of the study, as described in this article, flat fibrous structures from polypropylene and polylactide polymers were fabricated. The fabrication stage was necessary to determine the effect of the polymers' melt mass flow rate, melt electrospinning processing parameters (as a working distance and spinning voltage) on the resulting fiber diameter and on other physical and structural properties of the fibrous structures. An analysis of the effects of the processing parameters on the fabrication of the fibrous structures and the selection of the appropriate polymers for the final multilayered tubular structure were also performed.

Melt Electrospinning and Its Technologization in Tissue Engineering

“…The most frequent choices are metallic collectors: copper 32,48 aluminium, 21 or brass, 18 with flat 17 or tubular shapes with different diameters. 18,49 Zhou et al 48 were able to deposit polylactic acid (PLA) fibers of about 800 nm onto a cellulose filter media to test the efficiency of nanofibers on dust collection. Dalton et al 23 also used collectors modified with a reactive macromer to adhere and perform in vitro studies on the fibers.…”

Polymers for biomedical applications

“…This can include polymeric particles specifically targeted for release in specific conditions, such as the pH-sensitive carriers shown by Kong and coworkers, 1 or thermal-sensitive carriers as shown by Teixeira et al 2 Tissue engineering scaffolds are another area in which polymeric materials are widely employed, as in the work by Vozzi et al 3 Electrospun polymeric nanofibers also come in handy when designing vascular prostheses, as shown by Mazalevska et al 4 At the same time, topical applications such as wound dressings are feasible and they have generated an enormous body of literature, especially with respect to textiles and nonwoven fibrous materials. This is shown in the work of McCord and coworker 5 about nanofiber wound dressings, as well as in the article by Cusola et al 6 exemplifying long-term release of antibacterials.…”

Mathematical model for predicting topographical properties of poly (ε-caprolactone) melt electrospun scaffolds including the effects of temperature and linear transitional speed

“…Using melt electrospining, a variety of electrospun scaffolds with varied topographies can be produced with a high degree of controllability and reproducibility [3,4,9,10,18,19]. Electrospun microfibers present an excellent ability of controlling the topography of scaffolds for several tissue engineering applications in which the effect of physical cues would play a key role in studying cell-scaffold interactions [7,9].…”

“…Melt electrospinning is also preferred for biomaterials as there is no use of toxic solvents, unlike solution electrospinning [3,5,7,8,10]. Melt electrospinning can control the fiber diameter, which can be altered by adjusting parameters such as computer numerical control (CNC) feed speed, extrusion die nozzle diameter, melt temperature, flow rate, and electric field strength [9,12,17,18,[20][21][22][24][25][26].…”

“…The fabrication of such scaffolds requires an excellent degree of topographical controllability. Melt electrospining has been used as a powerful technique to achieve the controllability and also the reproducibility of topographical properties including fiber diameter, scaffold architecture, porosity and eventually mechanical properties such as elastic modulus [10,11,15,[20][21][22][23][24].…”