| 摘要: | 金屬凝膠( Metallogels )特殊的配位作用( Coordinative interactions )已被廣泛應用於生物醫學上，然而，在先前的研究中較少人討論金屬凝膠在傷口癒合方面的能力。在本研究中，我們利用多酚( polyphenols )和金屬離子的配位作用開發嶄新的天然金屬凝膠，使用低成本的多酚鞣酸（TA）和鈦離子（IV族）混合形成TA-TiIV凝膠。TA-TiIV凝膠的原位共凝膠化在結合不同功能性金屬離子具有良好的能力，因此，我們使用了五種金屬離子：鐵離子（Fe3+），銅（II）離子（Cu2+），鋅（II）離子（Zn2+），鈷（II）離子（Co2+）和鎳（II）離子（Ni2+） 進行抗菌測試，金屬凝膠在感染傷口的癒合過程中易受外部環境的pH和H2O2影響導致凝膠形成與崩解，透過紫外光/可見分光光譜( UV-Vis )和傅立葉轉換紅外光譜（FT-IR）對TA-TiIV金屬凝膠的化學式和配位結構進行量測，並進行電感耦合等離子體質譜法（ICP-MS）評估不同金屬離子的釋放能力，在先前的研究中TA-TiIV-CuII金屬凝膠已進行釋放速率研究(表5.5、7.4、8.4)。實驗結果顯示金屬離子釋放率具pH依賴性，且細菌的代謝過程導致酸性環境的產生，此外，TA-TiIV-CuII HG在含有H2O2的環境下與HRP結合導致釋放顯著的Cu2+離子。最後通過瓊脂擴散試驗( Agar diffusion test )評估金屬凝膠對大腸桿菌( Escherichia coli )、金黃色葡萄球菌（USA300）和表皮葡萄球 ( Staphylococcus epidermidis )的抗菌效果，以及細胞存活率分析( MTT assay )評估金屬凝膠對3T3細胞株的細胞毒性測試，結果顯示金屬凝膠具良好的生物相容性。在臨床感染傷口敷料應用上，TA-TiIV-CuII HG顯示具有抗菌效果，其感染傷口在8天後有明顯變小的趨勢，顯示TA-TiIV-CuII HG金屬凝膠有望成為感染傷口敷料應用的潛力材料。
;Metallogels were established based on coordinative interactions, exhibiting unique abilities, and being applied for various biomedical applications. However, the applications of metallogels for wound healing property has not been explored. In this study, we report a newly nature-derived metallogels developed by coordination of polyphenols and metal ions. Gelation occurs by mixing low-cost polyphenolic tannic acid (TA) and group (IV) metal ions (titanium ions) to form TA-TiIV gel. The TA-TiIV gel exhibits a good ability to incorporate diverse functional metal ions by in situ co-gelations. Herein, we used five metal ions: ferric ions (Fe3+), copper(II) ions (Cu2+), zinc(II) ions (Zn2+), cobalt(II) ions (Co2+) and nickel(II) ions (Ni2+) for antimicrobial tests. The formations and collapse of formed metallogels are sensitive to external pH – and the presence of H2O2, which displays in the healing process of infected wounds. The chemical and coordinative structures of TA-TiIV metallogel were characterized by UV-Vis spectrometer and Fourier-transform infrared (FT-IR) spectroscopy. The release of metal ions was evaluated by inductively coupled plasma mass spectrometry (ICP-MS), indicating the different releasing profiles upon the types of metal ions. For TA-TiIV-CuII metallogel, distinct releasing rates at different pH values of 5.5, 7.4 and 8.4 has been studied. The result indicates the pH-dependent metal ions release manner. Moreover, the bacterial environment has been investigated by UV-Vis spectrometer and pH meter, the result showed the acidic environment during the metabolism process of bacteria. Besides, HRP incorporated with TA-TiIV-CuII HG brought to a significant Cu2+ ions released, where H2O2 is presented. As the results, antibacterial effect of synthesized metallogels againsts Gram-negative Escherichia coli, and Gram-positive Methicillin-Resistant Staphylococcus aureus (USA300), Staphylococcus epidermidis bacteria has been investigated by agar diffusion test. Simultaneously, cytotoxicity of metallogels on NIH 3T3 fibroblast cell line was also explored by MTT assay, and turned out to be excellent biocompatibility. For clinical applications as infected wound dressings, TA-TiIV-CuII HG indicated the antimicrobial effect, led to significant smaller in wound area after 8 days, compared to TA-TiIV HG and Gauze. Consequently, demonstrated HG is promising a potential materials for infected wound applications.
Keywords- Metallogels, tannic acid (TA), metal ions, nature-derived |
