在傷口照護過程中，細菌等微生物的存在時常阻礙著組織修復的進程，因此抗菌傷口敷料的開發勢在必行，而水膠兼具膨潤性質、高生物相容性、高通透性的特色，也使其成為傷口敷料最有潛力的題材。
本研究選用殼聚醣 (Chitosan) 作為製作水膠的原料，在過去研究中顯示殼聚醣具備良好生物相容性、促進凝血功能，以及具備抗細菌、抗真菌的能力，再加上結構中含有大量胺基、羥基，對於後續修飾改質提高了可行性，這些特質對於傷口修復研究有很大的幫助，然而殼聚醣水膠的機械性質不佳也限制著應用的範圍，因此本研究利用硫代蘋果酸 (Mercaptosuccinic acid) 交聯殼聚醣高分子提升機械性質，並修飾桂皮醛 (Cinnamaldehyde) 與奈米銀抗菌成分，提升水膠抗菌能力，透過高解析核磁共振光譜儀 (NMR)、動態光散射分析 (DLS)、穿透式電子顯微鏡 (TEM)、場發射掃描式電子顯微鏡 (FE-SEM)、膨潤性質測試以及機械強度測試，分析修飾後化學結構、奈米銀尺寸、孔洞構造、水膠吸收液體情況與壓縮機械性質，透過共培養抗菌塗盤實驗評估靠菌能力，最後透過萃取液細胞毒性測試評估水膠的生物相容性。
綜合各實驗結果，桂皮醛與交聯劑添加不影響水膠孔洞樣貌，但會影響物理特性，桂皮醛含量越高，膨潤速率越慢，而交聯程度提升，平衡膨潤比下降但機械性質會明顯提升，且修飾桂皮醛與奈米銀後的CM11-cin-AgNPs水膠針對S. aureus及E. coli均具備99.9 %以上良好抗菌能力，同時又可以維持良好生物相容性，預期未來可以用於傷口敷料相關研究使用。

In the process of wound care, bacteria and other microorganisms often hinders the process of tissue repair, so the development of antibacterial wound dressings is imperative, and hydrogel has the characteristics of swelling properties, high biocompatibility, and high permeability, which makes it the most potential subject of wound dressing.
In this study, chitosan was selected as the raw material for making hydrogel. Past studies have shown that chitosan has good biocompatibility, promotes blood coagulation, and has anti-bacterial and anti-fungal capabilities. Contains a large number of amine groups and hydroxyl groups, which improves the feasibility of subsequent modification. However, the poor mechanical properties of chitosan hydrogel also limit the scope of application, so in this study, Mercaptosuccinic acid was used to cross-link chitosan polymer to improve the mechanical properties, and modified with cinnamaldehyde and silver nanoparticle to enhance the antibacterial ability.
Nuclear magnetic resonance spectroscopy (NMR), Dynamic Light Scattering Analysis (DLS), Transmission Electron Microscope (TEM), Field Emission Scanning Electron Microscope (FE-SEM), Swelling property test and Mechanical strength test were used to analyze the modified chemical structure, particle size, pore structure. The co-culture antibacterial test was used to analyze the antibacterial ability of different hydrogels and the biocompatibility of the hydrogel was evaluated through the cytotoxicity test.
Based on the experimental results, the appearance of internal pores structure would not be changed by the addition of cinnamaldehyde and crosslinker. However, the swelling rate decreased when the cinnamaldehyde content increased. The saturated swelling ratio would decrease if the degree of crosslinking increase, but at the same time the mechanical property would be improved. Overall, the CM11-cin-AgNPs hydrogel contains more than 99.9% antibacterial ability against S. aureus and E. coli and maintains good biocompatibility, enough mechanical property and swelling ratio, which shows the potential in wound dressings research.

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