本 實 驗 開 發 了 電 紡 絲 技 術 製 備 幾 丁 聚 醣/雙 相 磷 酸 鈣 (Chitosan/Biphasic Calcium Phosphate, CS/BCP) 奈 米 纖 維 的 程 序、 並 且 藉由調 整電 紡絲過程中的主要變因，包含電紡電壓、BCP濃度、電紡 率 及電極間距以得到直徑與結構最均勻的奈米纖維。
本研究利用光交聯反應以增加CS/BCP奈米纖維的穩定性。在電紡絲的過程中加入tetra-ethyleneglycol diacrylate (TTEGDA) 及 2,2-dimethoxy-2-phenylacetophenone(DMPA)，並結合UV光照 射 以 達 到 單 步 (one-step) 交 聯。藉由光交聯反應，本實驗得到有效率、可連續生產且具有良好穩定性的奈米纖維製備。藉由適合的交聯劑濃度及光照強度，CS/BCP電紡纖維膨潤度可以大幅的下降，並在水相中長時間維持其奈米纖維網狀結。同時，電紡纖維的型態並不會因光交聯反應而改變。
接著以骨母細胞的培養鑑別CS/BCP奈米纖維的生物相容性，且由其結果得知經光交聯反應後其生物相容性增加，這是因為藉由改善奈米纖維的機械性質可以增加細胞貼覆性與增殖力。纖維對骨細胞的親和性亦會因添加BCP而提升，其骨母細胞在培養的初期、中期及末期皆能有所增長。CS/BCP奈米纖維對於骨類細胞有相當的選擇性，此一結果可由非骨母細胞於此材料上難以生長而得知。本研究中所開發的CS/BCP奈米纖維具有生物相容性、良好的骨傳導性及在水溶液態中穩定，表現出作為骨組織工程支架的良好潛能。

In this research, chitosan/biphasic calcium phosphate (CS/BCP) nanofibers were prepared by electrospinning. The main parameters in electrospinning process, including applied voltage, BCP concentration, flow-rate and tip-to-collector distance, were optimized to obtaine most uniform CS/BCP nanofibers.
To enhance the stability of CS/BCP nanofibers, photocrosslinking was applied with the addition of tetra-ethyleneglycol diacrylate (TTEGDA) and 2,2-dimethoxy-2-phenylacetophenone (DMPA), where the UV irradiation was incorporated with electrospinning set-up and thus a one-step crosslinking was achieved. By using the photocrosslinking process proposed in this research, nanofibers with good stability were produced continuously and efficiently. With suitable crosslinker concentrations and irradiation energy, the swelling degree of CS/BCP electrospun fibers greatly decreased, keeping network structures of nanofibers in aqueous condition. Meanwhile, the morphology of nanofibers was not changed due to the photocrosslinking.
From the culture of osteogenic cells, the biocompatibility of CS/BCP nanofibrous substrates was identified and increased by the photocrosslinking. The enhancement in cell attachment and proliferation was caused by the improvement in nanofibers’ mechanical properties. The biocompatibility to osteoblasts was also promoted with the content of BCP. The osteogenic differentiation in early, middle and late stage was encouraged by the addition of BCP on nanofibrous substrates. The CS/BCP nanofibers were highly specific to osteogenic cells, revealed by difficulties in the growth of non-osteogenic cells on this composite nanofibrous scaffold. A modified electrospinning process which can continuously and easily produce biocompatible and osteoconductive CS/BCP nanofibers with high stability was developed in this study. The novel nanofibrous scaffolds showed great potential in the tissue engineering of bones.

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