جستجوی مقالات مرتبط با کلیدواژه "porosity" در نشریات گروه "مهندسی پزشکی"

The scaffolds for bone tissue engineering should consider the functional requirements: porosity, biocompatibility, and biodegradability. In this study, porous Poly (lactic-co-glycolic acid)/Hydroxyapatite composites were prepared with different weight ratios. Porous samples were fabricated by freeze-extraction method, coated with triblock copolymer and sterilized by UV. Then, human mesenchymal stem cells were cultured on scaffolds. Microstructural studies with SEM suggest the formation of about 50 micrometer size porous structure and interconnected porosity so that cells adhesion within the structure is well in depth in coated samples. DAPI fluorescence microscopy showed cells adhesion to the coated scaffolds and cells diffusion into the pores. Also, direct assay of cell proliferation performed with MTT test showed that, cells grew on the scaffold similar to or more than control samples result. Therefore, these findings suggest that the triblock-coated Poly (lactic-coglycolic acid)/ Hydroxyapatite porous composite scaffolds could provide cells adhesion and proliferation and are appropriate matrices for bone tissue engineering.

Gelatin is a protein which is derived from the organic constituent of bone (collagen). Combination of this protein with the inorganic constituent of bone (hydroxyapatite) may provide closer properties to the natural bone. In this study, a biodegradable composite scaffold based on gelatin and hydroxyapatite was prepared as a substitute for bone tissue. To increase the biocompatibility of this, composite, its fabrication was carried out without using any organic solvent. Porosities obtained were spontaneously achieved without any porogen. The pore morphology indicated a high interconnectivity with diameters ranging from 50 to 200 micrometers, which seems appropriate for bone tissue engineering applications. In order to study the biocompatibility of the scaffolds, mouse fibroblastic cells were used. After 24-hour cell culture period in vitro, suitable cell attachment was observed showing high biocompatibility for all the samples. Further examinations demonstrated that the best biocompatibility is obtained for the composite of 50 wt% hydroxyapatite and 50 wt% gelatin.