Author(s):
Martins, M. 
; Silva, S. S. ; Duarte, Ana Rita C. ; Reis, R. L.
Date: 2013
Persistent ID: http://hdl.handle.net/1822/27103
Origin: RepositóriUM - Universidade do Minho
Subject(s): Biomaterial; Starch cellulose acetate
Description
Publicado em "Journal of Tissue Engineering and Regenerative Medicine", vol. 7, supp. 1 (2013) Starch-based blends present an enormous potential to be widely used
in the biomedical area, because they are totally biodegradable, inexpensive,
available in large quantities. However, natural-based polymers
have great limitations in processability particularly due to their usually
high crystallinity which limits their solubility. This can be overcome by
the use of ionic liquids which are recognized as ‘green’ replacements for
conventional organic solvents. Earlier reports emphasized the use of
certain ionic liquids to solubilize some natural macromolecules such as
cellulose, starch, chitin, chitosan and silk fibroin. Furthermore, they
present unique physicochemical properties, namely lower vapour pressure,
excellent chemical and thermal stabilities, high ionic conductivity
and easy recyclability. Starch based materials have been proceed in a
variety of different morphologies and shapes by a number of different
processes. In this work, starch/cellulose acetate (SCA) was dissolved in
1-butyl-3-imidazolium acetate, followed by regeneration of the polymer
in different non-solvents (water, ethanol and isopropanol) in order to
obtain membranes. Different concentrations of SCA (5 and 10%) in
ionic liquid and drying techniques (vacuum oven and freeze drying)
were studied. The starch/cellulose acetate structures were evaluated by
their swelling capability, degradation behaviour and morphological features.
Moreover, the influence of thickness on physical chemical properties
of the membranes was assessed. The results revealed that
membranes with lower thickness showed high water absorption, which
by its turn accelerated their degradation rate. Furthermore, the membranes
dried by vacuum oven present a more compact structure as compared
those prepared by freeze drying. Some previous works reported
SCA as a suitable material for tissue engineering purposes, supporting
the cell adhesion. Then, in vitro cell culturing assays will be performed
using osteoblast like cells (SaOs-2) and mouse fibroblast-like cell line
(L929).The cell viability and proliferation on membranes will be evaluated
through the MTS test and the DNA quantification. The development
of innovative technology such as novel natural polymers
materials is of grater interest in medical field. All findings suggested
that the obtained structures (membranes) present adequate properties
for several biomedical applications for instance drug delivery, skin substitutes,
guided bone regeneration or as coatings for medical devices.
