INTEMA   05428
INSTITUTO DE INVESTIGACIONES EN CIENCIA Y TECNOLOGIA DE MATERIALES
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Development and characterization of electrospun scaffolds with enlarged pore size for tissue engineering applications
Autor/es:
J.I. IGARTÚA ROSELLÓ; P.R. CORTEZ TORNELLO; G.A. ABRAHAM; P.C. CARACCIOLO
Lugar:
Rosario
Reunión:
Congreso; 8th Latin American Congress of Artificial Organs, Biomaterials and Tissue Engineering (VIII COLAOB); 2014
Institución organizadora:
Sociedad Latinoamericana de Biomateriales, Ing. de Tejidos y Órganos Artificiales (SLABO)
Resumen:
The porous structure of electrospun scaffolds is an important aspect in the design of tissue engineered constructs, since the densely arranged architecture of electrospun fibers and small pores hinder efficient cellular infiltration or prevent three dimensional cellular integration. The growing need for porous structures has led to the development of many strategies applicable during the electrospinning or post-electrospinning procedures to increase the pore size of the electrospun scaffolds. The strategies to achieve larger macropores in electrospun mats include various methods, such as leaching of salt particles mixed with fibers during formation, growth of ice crystals in the collector during the electrospinning process, addition of sacrificial fibers and concurrent electrospinning and electrospraying, among many others. However, despite the improvements achieved, the cellular infiltration into micro/nanofibrous matrices still remains limited, or in many cases the strength decreases significantly. In this work, the preparation of scaffolds with large pores was carried out by using deposition/leaching of porogen particles in combination with electrospinning of polymer solutions. Electrospinning parameters were optimized to produce uniform bead-free polymeric microfibers. The solutions were prepared from biodegradable polymer poly(ε-caprolactone) (PCL, 80 Kg mol-1) in chloroform:methanol solvent mixtures (5:1 by volume) to 20 % wt. Scaffolds with enlarged pore size were obtained by alternating electrospinning with the incorporation of NaCl with different particle size (53-105 m, 149-250 m, 297-350 m) as porogen. The selective particle removal by dissolution in distilled water allowed the preparation of fibrous structures with higher pore size. The fibers surface was modified by chemical treatment with NaOH solutions to promote the partial hydrolysis of the ester groups in order to increase the hydrophilicity of the scaffolds. The morphology was studied by Scanning Electron Microscopy (SEM). The mean fiber diameter, fiber diameter distribution and overall porosities were determined by using an image analyzer (Image-Pro Plus). Fourier Transform Infrared Spectroscopy using Attenuated Total Reflectance mode (FTIR-ATR) and contact angle measurements were also employed to evaluate the hydrophilicity changes produced by the surface modification. The surface of PCL scaffolds displayed a typical electrospun structure of randomly oriented fibers, exhibiting a highly anisotropic fiber distribution, interconnected open macropores, and pore distribution throughout the structure, which evidenced samples with high porosity (over 90 %). The average fiber diameter was 5.15 ± 0.85 μm and exhibited an unimodal distribution of fiber diameters. Liquid extrusion porosimetry measurements are under progress, and the results will provide relevant information about pore size distribution.