Su Chunping, Zhao Huiping, Yang Hao, Chen Rong
School of Chemistry and Environmental Engineering, Key Laboratory for Green Chemical Process of Ministry of Education and Hubei Novel Reactor & Green Chemical Technology Key Laboratory, Wuhan Institute of Technology, Xiongchu Avenue, Wuhan 430073, PR China.
ACS Appl Bio Mater. 2019 Jan 22;2(1):171-181. doi: 10.1021/acsabm.8b00508. Epub 2019 Jan 11.
In this work, we developed a facile approach for the fabrication of stearic acid-modified starch/chitosan composite sponge with asymmetric wettability and gradient wettability via mediating the amount of starch. The starch/chitosan composite sponge exhibited heterogeneous wetting properties on its two surfaces after stearic acid modification. The superhydrophobic top surface with a water contact angle of 150° could prevent water, blood, and bacterial permeation without losing the breathability of the sponge, whereas the superhydrophilic bottom surface possessed optimal water and blood absorption and clotting abilities. The asymmetric wettability of starch/chitosan composite sponge was attributed to the synergistic contribution of gradient distribution of starch, rough three-dimensional skeleton structure induced capillary effect and the nonuniform surface distribution of hydrophilic/hydrophobic groups. Furthermore, the sponge also possessed good biodegradability and noncytotoxicity to the human normal hepatocyte. The results indicated that the stearic acid-modified starch/chitosan composite sponge with ideal liquid absorption, vapor transmission rate, self-cleaning and stain-repellent ability could be used as a promising candidate for wound dressing.
在本研究中，我们通过调节淀粉用量，开发了一种简便的方法来制备具有不对称润湿性和梯度润湿性的硬脂酸改性淀粉/壳聚糖复合海绵。硬脂酸改性后，淀粉/壳聚糖复合海绵在其两个表面表现出非均相的润湿特性。水接触角为150°的超疏水顶面可防止水、血液和细菌渗透，同时不丧失海绵的透气性，而超亲水底面则具有最佳的水和血液吸收及凝血能力。淀粉/壳聚糖复合海绵的不对称润湿性归因于淀粉的梯度分布、粗糙三维骨架结构引起的毛细管效应以及亲水/疏水基团的非均匀表面分布的协同作用。此外，该海绵对人正常肝细胞还具有良好的生物降解性和无细胞毒性。结果表明，具有理想液体吸收、蒸汽透过率、自清洁和防污能力的硬脂酸改性淀粉/壳聚糖复合海绵有望成为伤口敷料的候选材料。
