Jazmín I. González; Diana M. Escobar; Claudia P. Ossa
Abstract
Hydroxyapatite is one of the appropriate materials for hard tissue engineering because it is the inorganic structural constituent of bones and teeth, and hydroxyapatite has been evaluated to compare the mechanical properties, processing as scaffolds to evaluate the influence of porosity, since the elastic ...
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Hydroxyapatite is one of the appropriate materials for hard tissue engineering because it is the inorganic structural constituent of bones and teeth, and hydroxyapatite has been evaluated to compare the mechanical properties, processing as scaffolds to evaluate the influence of porosity, since the elastic modulus of material is influenced by the porosity, it is essential to establish a relationship between the two characteristics to obtain a material with optimum conditions for its implantation. The main objective of this research was to study the mechanical properties of hydroxyapatite scaffolds using compression and nanoindentation tests. The scaffolds were manufactured by gel-casting and gel-casting combined with foam polymer infiltration, in both cases 40 and 50% solids and three different monomers were used. The samples obtained by gel-casting exhibited a compressive strength between 0.93 and 6.15 MPa, an elastic modulus between 11.46 and 27.27 GPa; some of these scaffolds showed very similar values to human trabecular bone reported. In addition, samples produced by gel-casting combined with foam polymer infiltration, it was found that compressive strength was between 0.05 and 0.12 MPa, the elastic modulus between 1.61 and 6.24 GPa, concluding that the gel-casting produces scaffolds with closest to trabecular bone.

Igor Shishkovsky; Stanislav Volchkov; Vladimir Scherbakov; Larisa Volova
Abstract
Superparamagnetic oxide nanoparticles attract increasing attention in biomedical applications for tagging, imaging, separation and/or purification of cancer cells in living tissue. At the present study the selective laser sintering/melting (SLS/M) process using the Nd +3 YAG laser was carried out to ...
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Superparamagnetic oxide nanoparticles attract increasing attention in biomedical applications for tagging, imaging, separation and/or purification of cancer cells in living tissue. At the present study the selective laser sintering/melting (SLS/M) process using the Nd +3 YAG laser was carried out to fabricate and characterize polymer composites based on nano-oxides of FexOy type or of high-temperature superconductivity (HTS) of SrFe12O19 with bioresorbable polycaprolactone (PCL) powders and manufacture porous tissue engineering scaffolds. Practicability of the method for synthesis of functional-gradient three dimensional (3D) parts with magnetic nano-oxide particles and structural ordering were shown and appropriated laser regimes were assigned. The stem cellular morphometry, proliferative and adhesive activity to the 3D magnetic nanocomposites were compared. The medical tests show that all the 3D printed composites have biocompatible features. Medical potential of the SLS/M-fabricated superparamagnetic nano oxides for application as cell targeting systems and tissue engineering scaffolds is being discussed.

Javier Macossay; Faheem A Sheikh; Hassan Ahmad; Hern Kim; Gary L Bowlin
Abstract
Tissue engineering is a multidisciplinary field that has evolved in various dimensions in recent years. One of the main aspects in this field is the proper adjustment and final compatibility of implants at the target site of surgery. For this purpose, it is desired to have the materials fabricated at ...
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Tissue engineering is a multidisciplinary field that has evolved in various dimensions in recent years. One of the main aspects in this field is the proper adjustment and final compatibility of implants at the target site of surgery. For this purpose, it is desired to have the materials fabricated at the nanometer scale, since these dimensions will ultimately accelerate the fixation of implants at the cellular level. In this study, electrospun polyurethane nanofibers and their analogous nanofibers containing MWCNTs are introduced for tissue engineering applications. Since MWCNTs agglomerate to form bundles, a high intensity sonication procedure was used to disperse them, followed by electrospinning the polymer solutions that contained these previously dispersed MWCNTs. Characterization of the produced nanofibers has confirmed production of different non-woven mats, which include random, semi-aligned and mostly aligned patterns. A simultaneous and comparative study was conducted on the nanofibers with respect to their thermal stability, mechanical properties and biocompatibility. Results indicate that the mostly aligned nanofibers pattern presents higher thermal stability, mechanical properties, and biocompatibility. Furthermore, incorporation of MWCNTs among the different arrangements significantly improved the mechanical properties and cell alignment along the nanofibers.