纤维素/壳聚糖泡沫敷料制备及性能

Preparation and Properties of Cellulose/Chitosan Foam Dressing

采用LiOH/尿素/水溶剂体系溶解纤维素和壳聚糖,分别制得质量分数为2%的纤维素溶液和壳聚糖溶液;按一定比例混合均匀后,加入交联剂环氧氯丙烷和致孔剂SiO_(2)微粉,经交联、去除致孔剂和冷冻干燥等过程,制得了纤维素/壳聚糖泡沫敷料。通过扫描电子显微镜、力学性能、X射线衍射和体外生物学等表征表明,该敷料孔径约为300μm,当纤维素和壳聚糖质量比4∶1时制得的纤维素/壳聚糖泡沫综合性能最优,其为无定形结构,溶胀比达42且5 s即可达到溶胀平衡,储能模量约为2400 Pa,其水凝胶厚度为5 mm时透光率仍高于60%。该泡沫的水蒸气透过率达到3080 g/(m^(2)×24 h),溶血率仅为0.6%,15 min时的凝血指数为73%。该敷料具有制备工艺简单、低成本、多功能性等特点,为设计和制备新型皮肤创伤敷料提供了新思路。

Cellulose and chitosan solutions with mass fraction of 2%were prepared using LiOH/urea/H_(2)O solvent system.After mixing cellulose and chitosan solutions at a certain ratio,the cellulose/chitosan foams were obtained by chemical crosslinking,pore-forming agent removal and lyophilizing,using SiO2 powder as pore-forming agent and epichlorohydrin as crosslinking agent.Scanning electron microscopy,mechanical property,X-ray diffraction,in vitro biological tests were used to characterize properties of the foams.The results show that the foams have an average pore size of about 300μm.When the mass ratio of cellulose and chitosan is 4∶1,cellulose/chitosan foams have the best comprehensive performances,including amorphous structure,an equilibrium swelling ratio of 42,an equilibrium swelling time of about 5 s,and a storage modulus of about 2400 Pa.When the thickness of hydrated foam is 5 mm,light transmittance is still higher than 60%.Moreover,the water vapor transmittance of the foams reach 3080 g/(m^(2)×24 h),and their hemolysis rate and blood coagulation index at 15 min are 0.6%and 73%,respectively.The prepared foam dressing has the characteristics of simple preparation process,low cost and multifunction,which provides a creative idea for the preparation of new skin wound dressings.