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Proceedings of the 4th International Conference on Nanostructures (ICNS4) 12-14 March 2012, Kish Island, I.R. Iran Abstract Book |INST| Sharif University of Technology| 99 APP APP 065 APP 066 APP 067 NOTE . ....................................................... .................................................................... .................................................................... .................................................................... In this study, we report the synthesis and characterization of nano hy- droxyapatite (nHAp) in gelatine-starch matrix via simple method for in vitro bioactivity and biocompatibility evaluation. In vitro bioactivity of biocomposites is verified by carbonate apatite formation on their surfaces after immersion in simulated body fluid (SBF) for 3, 7 and 14 days. Cell culture and MTT assays revealed that nHAp could affect the proliferation of cells. The nHAp-gelatin - starch biocomposites had no negative effect on the cell morphology, viability and proliferation and possessed good biocompatibility. This study suggests that nHAp- gelatin- starch composite may be a prospective biodegradable biocom- posite for future medical applications. Keywords: Nano hydroxyapatite; Biocomposite; In-vitro; Biocompati- bilty; Bioactivity M. Meskinfam*, F. Jokari, M. Giahi, H. Jazdarrreh Department of Chemistry, Lahijan branch, Islamic Azad University, Lahijan, Iran *[email protected] In vitro Bioacvity and Biocompability Evaluaon of Nano Hydroxyapate-gelane-starch Biocomposites The ability to fabricate aligned nanofibers may open new avenues for the development of nerve regeneration using tissue engineering scaffolds. In this study, aligned poly(3-hydroxybutyrate)/poly(3-hydroxy butyrate- co-3-hydroxyvalerate) (PHB/PHBV) nanofibrous scaffolds were fab- ricated using electrospinning for the culture in vitro of Schwann cells (SCs) that physiologically assist in directing the growth of regenerating axons. The biocompatibility of the fabricated scaffolds was evaluated in terms of SCs adhesion and proliferation by DNA and metabolic activity quantification assays. In addition, scanning electron microscopy (SEM) and immunostaining analysis was performed to assess cell morphology and functionality. The results of this study showed that cells attached, proliferated and were metabolically active on scaffolds during 2 weeks of culture and positive for the SCs marker. Furthermore, SCs cultured on aligned nanofibers exhibited enhanced unidirectional cells orientation along the orientation of nanofibers and significantly higher proliferation and metabolic activity than those cultured on random nanofibers. Keywords: Aligned nanofibers; Scaffold; Schwann cells; Tissue en- gineering E. Masaeli a, b, c *, C.A. van Blitterswijk b , M. Morshed a , M. H. Nasr-Esfahani c , L. Moroni b a Department of Textile Engineering, Isfahan University of Technology, Isfa- han, 84156-83111, Iran b Department of Tissue Regeneration, University of Twente, 217, 7500 AE Enschede, The Netherlands c Department of Cell and Molecular Biology, Cell Science Research Center, Royan Institute for Animal Biotechnology, ACECR, Isfahan, 81589-68433, Iran * [email protected] Fabricaon and Cellular Compability of Aligned Poly(hydroxy alkanoate) Nanofibers for Nerve Tissue Engineering The aim of this study is comparing preparation methods of hydroxyap- atite-bioglass composite nanopowders which can be prepared in differ- ent routes based on sol-gel method for orthopaedic/dental applications. Nanostructure materials present a unique and incomparable character for orthopedic and dental implant. Hydroxyapatite-bioglass composite nanopowders with the same contents of bioglass (20%) as reinforce- ment have been prepared by using a sol-gel method in four routes: mix- ing sols before aging time, mixing bioglass sol with hydroxyapatite gel after gelation, mixing calcinated bioglass nanopowder with hydroxy- apatite sol, and mixing two calcinated powders by mechanical alloy- ing. Bioactive glass of the type CaO-P2O5-SiO2 was obtained by the source of tetraethylorthosilicate, triethylphosphate and calcium nitrate tetrahydrate. On the other hand, phosphoric pentoxide and also calcium nitrate tetrahydrate were applied as the source of hydroxyapatite. Calci- nation temperature was 600°C for both compositions. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDAX) techniques were used to investigate the microstructure and morphology of the nanopowders. Results indicated that because of different mixing time of hydroxyapatite with bioglass in either sol form, gel form or calcinated powder, the morphology, crystal- linity, crystallite size and composition of products were varied. bioglass remained amorphous in all routes of synthesis. Because of presence of amorphous bioglass, In situ synthesis of hydroxyapatite-bioglass com- posite nanopowders resulted in decreasing the crystallinity and the crys- tallite size of hydroxyapatite. Furthermore, by mixing two nanopowders after calcination, hydroxyapatite crystallinity was maximum and also by using this route proportion of two parts can be easily controlled. Keywords: Hydroxyapatite; Bioglass; Composite; Nanopowder; Sol-gel M. H. Taherian a *, M. Tamizifar a , M. H. Fathi b , H. Maleki Ghaleh c a Department of Materials and Metallurgical Engineering, Iran University of Science and Technology (IUST), Tehran, 16866-13114, Iran b Biomaterials Research Group, Department of Materials Engineering, Isfa- han University of Technology, Isfahan, 84156-83111, Iran c Faculty of Materials Engineering, Sahand University of Technology, Ta- briz, 5331711111, Iran *[email protected] Modified Sol-gel Method for Synthesis of Hydroxyapa- te-bioglass Nanocomposite The aim of this work was preparation and characterization of na- no-structured, fluoridated hydroxyapatite (FHA) bulks from FHA nanopowders with different degree of fluoridation (Ca10(PO4)6(OH)2- xFx: where x were selected equal to 0.0, 0.5, 1.0, 1.5, and 2.0) via two step sintering method. Initial and secondary temperatures (T1 and T2) of each step, initial and secondary holding times (t1 and t2) and compac- tion pressure (P) effects on densification and grain growth were deter- mined. Characterization of the prepared FHAs bulks were performed by X-ray diffraction. As result shown, dense FHA bioceramics were obtained with an average grain size of ~110 nm under the conditions T1= 1000°C (for x= 0.0, 0.5, and 2.0) and T1= 1025°C (for x= 1.5), T2= 900°C, t1= 10min, t2= 24hr, and P= 200MPa. The mentioned materi- als in comparison with other researches results were produced with approximate theoretical density (TD) in lower sintering temperature, small grain growth and without any thermal decomposition. Keywords: Bioceramics; Fluorapatite; Hydroxyapatite; Two step sin- tering; Nanostructure M. H. Esnaashary*, M. H. Fathi, M. Ahmadian Biomaterials Research Group, Department of Materials Engineering, Isfa- han University of Technology, Isfahan, 84156-83111, Iran *[email protected]
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Proceedings of the 4th International Conference onNanostructures (ICNS4)12-14 March 2012, Kish Island, I.R. Iran
Abstract Book |INST| Sharif University of Technology| 99
APP
APP 065
APP 066
APP 067
NOTE . ....................................................... .................................................................... .................................................................... ....................................................................
In this study, we report the synthesis and characterization of nano hy-droxyapatite (nHAp) in gelatine-starch matrix via simple method for in vitro bioactivity and biocompatibility evaluation. In vitro bioactivity of biocomposites is verified by carbonate apatite formation on their surfaces after immersion in simulated body fluid (SBF) for 3, 7 and 14 days. Cell culture and MTT assays revealed that nHAp could affect the proliferation of cells. The nHAp-gelatin - starch biocomposites had no negative effect on the cell morphology, viability and proliferation and possessed good biocompatibility. This study suggests that nHAp-gelatin- starch composite may be a prospective biodegradable biocom-posite for future medical applications.Keywords: Nano hydroxyapatite; Biocomposite; In-vitro; Biocompati-bilty; Bioactivity
M. Meskinfam*, F. Jokari, M. Giahi, H. JazdarrrehDepartment of Chemistry, Lahijan branch, Islamic Azad University, Lahijan, Iran*[email protected]
In vitro Bioactivity and Biocompatibility Evaluation of Nano Hydroxyapatite-gelatine-starch Biocomposites
The ability to fabricate aligned nanofibers may open new avenues for the development of nerve regeneration using tissue engineering scaffolds. In this study, aligned poly(3-hydroxybutyrate)/poly(3-hydroxy butyrate-co-3-hydroxyvalerate) (PHB/PHBV) nanofibrous scaffolds were fab-ricated using electrospinning for the culture in vitro of Schwann cells (SCs) that physiologically assist in directing the growth of regenerating axons. The biocompatibility of the fabricated scaffolds was evaluated in terms of SCs adhesion and proliferation by DNA and metabolic activity quantification assays. In addition, scanning electron microscopy (SEM) and immunostaining analysis was performed to assess cell morphology and functionality. The results of this study showed that cells attached, proliferated and were metabolically active on scaffolds during 2 weeks of culture and positive for the SCs marker. Furthermore, SCs cultured on aligned nanofibers exhibited enhanced unidirectional cells orientation along the orientation of nanofibers and significantly higher proliferation and metabolic activity than those cultured on random nanofibers.Keywords: Aligned nanofibers; Scaffold; Schwann cells; Tissue en-gineering
E. Masaelia, b, c*, C.A. van Blitterswijkb, M. Morshed a, M. H. Nasr-Esfahani c, L. Moroni ba Department of Textile Engineering, Isfahan University of Technology, Isfa-han, 84156-83111, Iranb Department of Tissue Regeneration, University of Twente, 217, 7500 AE Enschede, The NetherlandscDepartment of Cell and Molecular Biology, Cell Science Research Center, Royan Institute for Animal Biotechnology, ACECR, Isfahan, 81589-68433, Iran* [email protected]
Fabrication and Cellular Compatibility of Aligned Poly(hydroxy alkanoate) Nanofibers for Nerve Tissue Engineering
The aim of this study is comparing preparation methods of hydroxyap-atite-bioglass composite nanopowders which can be prepared in differ-ent routes based on sol-gel method for orthopaedic/dental applications. Nanostructure materials present a unique and incomparable character for orthopedic and dental implant. Hydroxyapatite-bioglass composite nanopowders with the same contents of bioglass (20%) as reinforce-ment have been prepared by using a sol-gel method in four routes: mix-ing sols before aging time, mixing bioglass sol with hydroxyapatite gel after gelation, mixing calcinated bioglass nanopowder with hydroxy-apatite sol, and mixing two calcinated powders by mechanical alloy-ing. Bioactive glass of the type CaO-P2O5-SiO2 was obtained by the source of tetraethylorthosilicate, triethylphosphate and calcium nitrate tetrahydrate. On the other hand, phosphoric pentoxide and also calcium nitrate tetrahydrate were applied as the source of hydroxyapatite. Calci-nation temperature was 600°C for both compositions. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDAX) techniques were used to investigate the microstructure and morphology of the nanopowders. Results indicated that because of different mixing time of hydroxyapatite with bioglass in either sol form, gel form or calcinated powder, the morphology, crystal-linity, crystallite size and composition of products were varied. bioglass remained amorphous in all routes of synthesis. Because of presence of amorphous bioglass, In situ synthesis of hydroxyapatite-bioglass com-posite nanopowders resulted in decreasing the crystallinity and the crys-tallite size of hydroxyapatite. Furthermore, by mixing two nanopowders after calcination, hydroxyapatite crystallinity was maximum and also by using this route proportion of two parts can be easily controlled.Keywords: Hydroxyapatite; Bioglass; Composite; Nanopowder; Sol-gel
M. H. Taheriana*, M. Tamizifara, M. H. Fathib, H. Maleki Ghalehc
a Department of Materials and Metallurgical Engineering, Iran University of Science and Technology (IUST), Tehran, 16866-13114, Iranb Biomaterials Research Group, Department of Materials Engineering, Isfa-han University of Technology, Isfahan, 84156-83111, Iranc Faculty of Materials Engineering, Sahand University of Technology, Ta-briz, 5331711111, Iran*[email protected]
Modified Sol-gel Method for Synthesis of Hydroxyapa-tite-bioglass Nanocomposite
The aim of this work was preparation and characterization of na-no-structured, fluoridated hydroxyapatite (FHA) bulks from FHA nanopowders with different degree of fluoridation (Ca10(PO4)6(OH)2-
xFx: where x were selected equal to 0.0, 0.5, 1.0, 1.5, and 2.0) via two step sintering method. Initial and secondary temperatures (T1 and T2) of each step, initial and secondary holding times (t1 and t2) and compac-tion pressure (P) effects on densification and grain growth were deter-mined. Characterization of the prepared FHAs bulks were performed by X-ray diffraction. As result shown, dense FHA bioceramics were obtained with an average grain size of ~110 nm under the conditions T1= 1000°C (for x= 0.0, 0.5, and 2.0) and T1= 1025°C (for x= 1.5), T2= 900°C, t1= 10min, t2= 24hr, and P= 200MPa. The mentioned materi-als in comparison with other researches results were produced with approximate theoretical density (TD) in lower sintering temperature, small grain growth and without any thermal decomposition.Keywords: Bioceramics; Fluorapatite; Hydroxyapatite; Two step sin-tering; Nanostructure
M. H. Esnaashary*, M. H. Fathi, M. AhmadianBiomaterials Research Group, Department of Materials Engineering, Isfa-han University of Technology, Isfahan, 84156-83111, Iran*[email protected]
