壓瘡 (Pressure ulcers, PU) 為臥床不起或行動不便之患者常見的併發症，影響的族群常見有長者及身障人士，除了使其生活品質下降，若治療不當甚至可能導致嚴重感染及死亡。因此，開發針對於 PU 的新療法非常重要。
近年來應用於組織再生及修復的傷口敷料備受關注，而幾丁聚醣 (Chitosan, CS) 是一種由幾丁質 (Chitin) 水解後得到的多醣，因有助於傷口癒合而受到廣泛研究。CS 已被證明具有抗菌能力，同時具有促進細胞增殖和遷移、血管生成及膠原蛋白合成等特性，使其常應用於促傷口癒合的材料。單寧酸 (Tannic acid, TA) 因擁有生物相容性、抗菌、抗氧化、促進組織修復和製備方法簡單等優勢，被大量的應用在生醫材料中。在本研究中製備了一款新型水凝膠，將苯胺四聚體 (Aniline tetra, AT) 接枝到 CS 上，以戊二醛 (Glutaraldehyde, GA) 為交聯劑形成 CS 接枝 AT 的導電水凝膠 (CS-GA-AT, CGA)。再於水凝膠內搭載 TA 藥物，形成載有 TA 的 CS 接枝 AT 導電水凝膠 (CS-GA-AT-TA, CGAT)，以期能進一步提高電刺激 (Electrical stimulation, ES) 對 PU 的治療效果。
本實驗藉由傅立葉轉換紅外光譜、核磁共振光譜與熱重損失性質分析探討材料接枝前後的化學結構變化，再透過溶脹、形態學、電導率、流變性質及藥物釋放評估水凝膠之性質，結果顯示 CGAT 具有良好的機械性能與生物相容性。綜上所述，使用載有 TA 藥物的 CGA 水凝膠在治療 PU 具有潛力，這些材料的組合應能促進傷口癒合和組織再生，期望未來可以為 PU 治療提供一種有效且方便的新型材料。

Pressure ulcers (PU) are a common complication for patients who are bedridden or have limited mobility, especially for the elderly and disabled. PU greatly affect their quality of life and may lead to serious infections and even death. Therefore, it is important to develop new treatments for PU. Currently, the main treatments for PU are topical treatment and oral medications.
In recent years, there has been increasing interest in the use of biomaterials for wound healing and tissue regeneration. Chitosan (CS), a natural polycationic linear polysaccharide derived from chitin, has been widely studied for its ability to facilitate wound healing. CS has been demonstrated to have antimicrobial properties, promoting cell proliferation and migration, angiogenesis and collagen synthesis that make CS a promising material for wound healing.
Tannic acid (TA) can be prepared easily and possesses biocompatibility, antibacterial properties, antioxidant capabilities and wound-healing effects. In the study, we prepared and characterized the aniline tetra (AT) was grafted on CS using glutaraldehyde (GA). TA was encapsulated in AT-grafted CS (CGA) hydrogel to form (CGAT) hydrogel. The prepared materials were characterized by Fourier-transform infrared spectroscopy and nuclear magnetic resonance spectroscopy and thermogravimetric analysis. The properties of the developed hydrogel were evaluated through swelling, morphology, electrical conductivity, rheological properties, in-vitro drug release study and in-vitro biocompatibility. These results suggested that developed CGAT hydrogel may have potential in the treatment of PU.

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