Mechanical and biological properties of bio-based scaffolds for tissue regeneration
Carregando...
Data
Data de publicação
2016
Orientador
Título da Revista
ISSN da Revista
Título do Volume
É parte de
É parte de
É parte de
É parte de
CONGRESSO LATINO-AMERICANO DE ORGAOS ARTIFICIAIS E BIOMATERIAIS, 9; CONGRESSO DA SOCIEDADE LATINO AMERICANA DE BIOMATERIAIS, ORGAOS ARTIFICIAIS E ENGENHARIA DE TECIDOS, 13.
Exportar
Resumo
Green polymers derived from vegetable oils are promising materials for production of scaffolds
for tissue engineering due to their low cost, availability and biodegradability. Unsaturated
vegetable oils could be precisely engineered at a molecular level into renewable polymeric
scaffolds in a way similar to some polymers derived from petroleum-based monomers. The
reactivity of the unsaturated bonds of the triglycerides is what allows vegetable oil to be used in
oil based polymers. Herein we report the first preparation of scaffolds for tissue engineering based
on semi-interpenetrating networks from soybean oil. Materials and Methods: Initially, epoxidized
soybean oil (ESO) was synthesized by the Prileshjew’s reaction. A solution of soybean oil (284
mM) and glacial formic acid (304 mM) was heated at a 50°C. Sulfuric acid (5 mM) was added into
the solution. Then, H2O2 solution (1,032 mM) was added slowly from a dropping funnel and
reacted at 50 °C for 7 h. The molar ratio of soybean oil: formic acid: hydrogen peroxide was 1:3:9.
The crude product was filtered and washed thoroughly with distilled water until a pH of 7.0 was
obtained. The oil phase was dried with anhydrous sodium sulfate and then filtered. Finally, the
residual water was removed using a rotary evaporator at 50°C under vacuum. The epoxidation
degree (ED) of ESO was calculated from the 1H-NMR. An ED of 75 % was obtained. Acrylated
epoxidized soybean oil (AESO) was prepared after reaction between ESO and 2-hydroxyethyl
methacrylate (HEMA). About 60 mM of ESO were placed in a 250 mL round-bottom flask
equipped with a magnetic stirrer and a reflux condenser. Hydroquinone was used as a free radical
inhibitor. The molar ratio of ESO: HEMA was 10:1. The reaction temperature under nitrogen
atmosphere and time was 120 °C and 7 h, respectively. The reactional mixture was cooled to
room temperature (25 oC) and diluted with hexane before purifying by thoroughly washing with
distilled water. The final step was dehydration with anhydrous sodium sulfate and the solvent was
evaporated using an evaporator. The number of HEMA groups/molecule of the resulting product
was determined from the 1H-NMR spectrum. A mixture of AESO and 1 wt% of benzoyl peroxide
was heated at 70°C for 20 min in a closed container before casting into a glass mold. Then, the
mixture was cured at 90°C for 20 min in a thermal oven and at 90°C for 30 min in a vacuum oven
sequentially. After washed thoroughly with distilled water the obtained membranes were
lyophylized. Results and Discussion: Membrane surface and cross-section morphologies of the
bio-based scaffolds were visualized by using SEM. As shown in this series of images, all the
membranes have asymmetric structure consisting of a thin fine porous selective layer and much
thicker porous sub-structure. The glass transition temperature (Tg) of the bio-based scaffolds
were studied by differential scanning calorimetry (DSC). The Tg of PHEMA was 94°C while the
Tg of the scaffold were in the range of –9 to 50°C. This may be due to the flexible and relatively
short chains of the triglyceride in the produced bio-based scaffold contributed to the lower Tg.
The Tg also depended on the number of HEMA groups. It was observed that more HEMA groups
caused more crosslinking and produced a higher Tg. The biocompatibility evaluation of the biobased
scaffolds provides encouraging indications for long-term safety. In fact, in the cytotoxicity
study, the material extracts did not induce toxic effects on the Chinese hamster ovary (CHO) cells,
showing high cell viability of the synthesized bio-based scaffolds. The values of Young modulus
(250 kPa) along with the calculated molecular weight between crosslinks for swollen bio-based
scaffolds were determined. As expected, the E value increased with increasing HEMA
concentration in AESO due to the increased crosslinking density. However, the E values obtained
for the bio-based scaffolds were comparable to human skin. Conclusions: The results obtained in
this work indicate that the bio-based scaffolds could be a good candidate for the biomedical
applications, such as wound dressing and scaffolds for tissue engineering. The authors would like
to acknowledge the financial support from the CNPq, CAPES, FAPEMIG and FINEP.
Como referenciar
HIGA, O.Z.; CARNEIRO, T.M.; QUEIROZ, A.A. de; BARATELA, F.J.; SILVA, F.M. da. Mechanical and biological properties of bio-based scaffolds for tissue regeneration. In: CONGRESSO LATINO-AMERICANO DE ORGAOS ARTIFICIAIS E BIOMATERIAIS, 9; CONGRESSO DA SOCIEDADE LATINO AMERICANA DE BIOMATERIAIS, ORGAOS ARTIFICIAIS E ENGENHARIA DE TECIDOS, 13., 24-27 de agosto, 2016, Foz do Iguaçu, PR. Abstract... p. 732-732. Disponível em: http://repositorio.ipen.br/handle/123456789/27468. Acesso em: 29 Apr 2026.
Esta referência é gerada automaticamente de acordo com as normas do estilo IPEN/SP (ABNT NBR 6023) e recomenda-se uma verificação final e ajustes caso necessário.