Three Dimensional Nanofibrous Scaffold of Chitosan/Strontium-Substituted Calcium Phosphate for Bone Tissue Engineering

• Main Authors: Shang-ChiTsai, 蔡尚旂
• Other Authors: Tzer-Min Lee
• Format: Others
• Language: en_US
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/78563503267552295320

碩士 === 國立成功大學 === 生物醫學工程學系 === 103 === Because of the biocompatibility, biodegradability, and better mechanical properties, chitosan is a good choice for tissue engineering materials. In the applications of tissue engineering, chitosan has been used for cell cultures. For example, bone, cartilage, skin, nerve and so on. Among the above, bone and cartilage cells are the most used in the cell culture. Chitosan has many attractive properties to be good culture template owing to the promoting wound healing and antibiotic. Hydroxyapatite (HA) is one of the major compositions in human bone. Due to its good biocompatibility, osteoconductivity, non-toxic, and non-irritating, hydroxyapatite is a good material of implants. Strontium (Sr) is a trace element in human body and 98% of the total content exists in the skeleton. It can enhance the number and activity of osteoblasts as well as reduce the number and activity of osteoclasts. Therefore, Sr-substituted hydroxyapatite (SrHA) also can improve bone formation and inhibit bone resorption. In this study, HA and SrHA are synthesized under chemical precipitation method and hydrothermal method. Microstructure was observed with transmission electron microscopy (TEM). Through the analyses of energy dispersive x-ray spectroscopy (EDS), X-ray diffraction (XRD), and Fourier transform infrared spectrometer (FTIR), the calcium phosphate with syntheses was mainly hydroxyapatite and combined with strontium. Bioceramics and polymers have some defects. Consequently, chitosan, HA and SrHA are used to be bone repair materials in this study. Besides, the popular and novel technique Electrospinning was used to fabricate chitosan nanofibrous scaffolds containing calcium phosphate. Electrospining provided porous structures which are quite similar to the extracellular matrix (ECM). With field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM), the images showed the calcium phosphate particles were well-dispersed in the nanofibers. With the spectrums of energy dispersive x-ray (EDS), X-ray diffraction (XRD), and Fourier transform infrared (FTIR), the existence of calcium phosphate was proved. After 14-day immersion in SBF, SEM images showed the deposition of apatite on the surface and the release of strontium ion in SBF was observed through inductively coupled plasma-mass (ICP) analysis. In vitro test, by Alamar blue and ALP assay, cells (MC3T3-E1) proliferate and differentiate the most at the scaffolds containing SrHA and the scaffolds are suitable for bone tissue repair.