DESENVOLVIMENTO DE ARCABOUÇOS FIBROSOS À BASE DE BLENDAS POLIMÉRICAS DE PULULANA E DE PVA POR ROTOFIAÇÃO PARA ENGENHARIA DE TECIDO DE PELE
The main hindrances for cost effective skin injury treatments are tightly associated to the limited number of donors and the immunogenic reactions triggered by antigens present in the grafts. Beside the intense research and development in tissue engineering and regenerative medicine, Human Skin Equivalents (HSE) have been proposed both as clinical skin substitutes, due to their biocompatibility and non-immunogenicity, and models for permeation and toxicity studies. Since the last decades, the investigations of scaffolds, as framework environments for cell growth, have shown a boom of interest. It seems undoubtedly that a fibrous three-dimensional structure may reliably mimic the extracellular matrix. A large number of techniques has been used to produce fibrous mats, among which Rotary Jet-Spinning (RJS) appears undoubtedly as one of the most efficient. However, an important open challenge remains for the optimization of experimental design to get a fine control of the fibers morphology and size, as well as for the mat homogeneity and reproducibility. In this work, we present an experimental study on the formation process of polymer fibrous scaffolds, based on a biopolymer, Pullulan - PULL, and a synthetic polymer, Poly (vinyl alcohol) - PVA, by means of Rotary Jet-Spinning (RJS) technique. We have analyzed the influence of the polymer composition (X1), solvent volatility (X2) and RJS collector distance (X3) on the fibers diameter (Y). The ranges of independent variables were 0:100–0:100 for the PULL:PVA blend composition, 0–100% for DMSO percentage in DMSO/H2O solvent mixture, 4–9 cm for collector distance. To minimize the number of required experiments for a complete evaluation, Response Surface Methodology (RSM) and Central Composite Rotatable Design (CCRD) have been performed using the Expert Design Software. The nanofiber morphology and thermal properties have been analyzed by scanning electron microscopy (SEM) and thermogravimetric measurements, respectively. It was found that the fibers diameter ranged from 300 nm to 1500 nm, depending on the for collector distance, and tightly on the rheological properties of polymer solution. The RSM analysis showed that a quartic model could best fit the experimental results.
The main hindrances for cost effective skin injury treatments are
tightly associated to the limited number of donors and the immunogenic
reactions triggered by antigens present in the grafts. Beside the
intense research and development in tissue engineering and regenerative
medicine, Human Skin Equivalents (HSE) have been proposed both as
clinical skin substitutes, due to their biocompatibility and
non-immunogenicity, and models for permeation and toxicity studies.
Since the last decades, the investigations of scaffolds, as framework
environments for cell growth, have shown a boom of interest. It seems
undoubtedly that a fibrous three-dimensional structure may reliably
mimic the extracellular matrix. A large number of techniques has been
used to produce fibrous mats, among which Rotary Jet-Spinning (RJS)
appears undoubtedly as one of the most efficient. However, an important
open challenge remains for the optimization of experimental design to
get a fine control of the fibers morphology and size, as well as for the
mat homogeneity and reproducibility. In this work, we present an
experimental study on the formation process of polymer fibrous
scaffolds, based on a biopolymer, Pullulan - PULL, and a synthetic
polymer, Poly (vinyl alcohol) - PVA, by means of Rotary Jet-Spinning
(RJS) technique. We have analyzed the influence of the polymer
composition (X1), solvent volatility (X2) and RJS collector distance
(X3) on the fibers diameter (Y). The ranges of independent variables
were 0:100–0:100 for the PULL:PVA blend composition, 0–100% for DMSO
percentage in DMSO/H2O solvent mixture, 4–9 cm for collector distance.
To minimize the number of required experiments for a complete
evaluation, Response Surface Methodology (RSM) and Central Composite
Rotatable Design (CCRD) have been performed using the Expert Design
Software. The nanofiber morphology and thermal properties have been
analyzed by scanning electron microscopy (SEM) and thermogravimetric
measurements, respectively. It was found that the fibers diameter ranged
from 300 nm to 1500 nm, depending on the for collector distance, and
tightly on the rheological properties of polymer solution. The RSM
analysis showed that a empirical model could best fit the experimental
results.