Study on Polycaprolactone Coated Hierarchical Meso/ Macroporous Titania Scaffolds for Bone Tissue Engineering

Document Type : Original Article


1 Department of Biomedical Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran

2 Department of Materials Engineering, Shahreza Branch, Islamic Azad University, Shahreza, Isfahan, Iran


In this study, the effect of polycaprolactone (PCL) coating on the mechanical strength, cell behavior and cell attachment of the hierarchical meso/macroporous Titania scaffold were investigated. Titania scaffold as the substrate was fabricated through the evaporation-induced self-assembly coupled with the foamy method. Then prepared scaffolds were coated by polycaprolactone solution with three different weight percentages by the dip-coating method. SAXS, WAXRD, SEM, compressive strength, MTT and cell attachment test were applied to characterized the samples. Based on XRD results, as polycaprolactone concentration increased, the intensity of the crystalline polycaprolactone phase increased while the TiO2 peak intensity decreased due to the covering of mesoporous titania by polycaprolactone. Compressive strength showed that by increasing polycaprolactone percent, the porosity decrease from 89.5 to 73.8 % which caused increasing strength from 0.2 to 0.79 MPa. The SEM results illustrated that by increasing polycaprolactone concentration from 1.2 to 1.5 wt%, the macrospores were filled by polycaprolactone. In this regard, The sample containing 1wt% polycaprolactone was choosen as the selective sample. Also, the MTT test reported a small trace of cytotoxicity in contact with the L929 mouse fibroblast cells. The cell attachment test that was performed by using MG63 cells, showed that the coated samples provided the suitable substrate for cells to attach and also showed cell viability on the surface of the coated substrate. Overall, according to the results, the hierarchical meso/macroporous Titania scaffold coated with 1 wt% polycaprolactone, could have good potential to be used in tissue engineering.


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