聚丙烯不織布經由電漿活化處理可親水化及含過氧化基,親水化後可直接複合水溶性生解材料水膠當作生醫塡補材料之補強材;此外也可利用紫外光接枝聚台,與感溫性異丙基丙烯醯胺(N-isopropylacrylamide,簡稱NIPAAm)單體接枝聚合,若同時加入三種添加劑,則可形成異丙基丙烯醯胺的水膠複合物,吸水膨潤具有易剝離特性。接著利用聚異丙基丙烯醯胺所含的氨官能基(-NH2)的結構,藉由戊二醛(Glutoraldehydy,簡稱GA)交聯劑,可於表面交聯固定上天然生解性明膠水膠材。結果顯示,戊二醛交聯劑濃度的高低及明膠生解物的交聯方式,會影響生解物明膠的機械性質及強度。其中二階段交聯法配合冷凍乾燥處理,可成功製得孔洞大小約20~100μm的海綿狀組織結構。爲了應用於傷口組織修復的支架,初步從體外的纖維母細胞成長及增殖的實驗結果發現,此複合水膠敷料較細胞用培養皿提供更快的生長環境,具有良好的組織親和性。
In the study, we are going to develop a tri-layer membrane as the artificial skin for extensive burn injury. The first layer is composed by polypropylene (PP) non-woven fabric, which provides an open structure for exudates drainage out and reduces the risk of second infection. The second layer is as so called auto-stripped layer composed by poly-N-isopropyacrylamide (PNIPAAm). The layer will be automatically peeled off from the tri-copolymer layer once the wound site closed and recovered. The third layer is a 3-dimensional tri-copolymer sponge of gelatin with 70% in porosity and 20-100μm in pore size. The layer is constructed as a dermis analogous layer to stimulate capillaries penetration, promote dermal fibroblast migration and induce the secretion of extra-cellular matrix, which provide a better physiological environment for burn defect recovery. The tri-layer wound dressing has been successfully prepared by a series functional modification. First, PP nonwoven was activated by argon gas plasma and subsequently UV-light graft-polymerization with NIPAAm monomer. At the same time, three additives were added to form the PNIPAAm hydrogel. Then, due to the special functional group (-NH2) of PNIPAAm, it can be further chemical binding with biodegradable polymers- gelatin by the aid of GA crosslinking agent. After lyophilized process, the porous structure and morphology of this tri-layer composite were all observed by 8PM. Finally, from the in vitro fibroblast cell culture results, this tri-layer dressing really provides a good space and circumstance to introduce the cells growth and proliferation.