The influence of electrospinning parameters on polydioxanone scaffold properties

Abstract

Conduits currently used to reconstruct the right ventricular outflow tract (RVOT) have no growth potential and require reoperations, resulting in an increased level of morbidity and mortality. This work investigates the effect of electrospinning parameters on the mechanical properties and biocompatibility of bioresorbable tubular scaffolds, as part of a program to develop a tissueengineered valved tube for RVOT replacement. Electrospinning was used to develop tubular scaffolds of polydioxanone, with the experimental parameters systematically varied. Three electrospinning parameters (volume of liquid, flow rate, and speed of mandrel rotation) were investigated, and their effects on the mechanical properties and cellular response of the scaffolds were analysed using scanning electron microscopy, X-ray diffraction, differential scanning calorimetry, gas chromatography, uniaxial tensile tests, cell viability and cytotoxicity assays. Mechanical properties were compared to those of the native RVOT reported in the literature. Increasing the mandrel rotation speed tended to increase fibre alignment slightly, and led to more profound rises in the stress at failure and Young's modulus. An increase in flow rate also increased the rigidity of the tubes. Cell viability and cytotoxicity assays showed all the tubes produced to have excellent biocompatibility. Through variation of the processing parameters, it is possible to tune mechanical properties of medical-grade polymer tubes over a wide range. By using a mandrel rotation speed of 50 rpm and a flow rate of 20 mL/h or higher we can prepare materials with Young's modulus, strain at failure, and tensile stress close to the native tissue. Electrospinning therefore offers great promise in the development of scaffolds to match the properties of the native RVOT, paving the way to a future bioresorbable device to replace the RVOT in children.

Biomaterial aided differentiation and maturation of induced pluripotent stem cells

“…Among the synthetic polymers, polyesters are the common material used for biomaterial scaffold fabrication because as they are readily degraded by hydrolysis of ester bonds, which further facilitates the degradation through metabolic pathways causing minimal toxicity to the hosts. Poly(acrylonitrile-co-methylacrylate) (Hosseini, Pan, & Ko, 2017) and polydioxanone (Ahmad et al, 2018) are the other synthetic polymer materials fabricated as electrospun fibers to induce cell growth. Although synthetic materials offers flexibility to get modified by addition of peptides or moieties for cell binding, release of unfavorable byproducts during degradation which impedes and bioincompatibility and, which hampers tissue regeneration in vivo poses critical concerns (Francois, Dorcemus, & Nukavarapu, 2015).…”