Bio-derived crystalline silk nanosheets for versatile macroscopic assemblies  

作　　者：Baochang Cheng Zhouyue Lei Peiyi Wu 

机构地区：[1]State Key Laboratory for Modification of Chemical Fibers and Polymer Materials,College of Chemistry,Chemical Engineering and Biotechnology,Center for Advanced Low-Dimension Materials,Donghua University,Shanghai 201620,China [2]John A.Paulson School of Engineering and Applied Sciences,Harvard University,Cambridge,MA 02138,USA [3]State Key Laboratory of Molecular Engineering of Polymers,Department of Macromolecular Science and Laboratory of Advanced Materials,Fudan University,Shanghai 200433,China

出　　处：《Nano Research》2022年第6期5538-5544,共7页纳米研究（英文版）

基　　金：The authors gratefully acknowledge the financial support from the National Natural Science Foundation of China(Nos.51973035 and 51733003).

摘　　要：Silk fibroin with sophisticated hierarchical architectures from nano to macro scale shows excellent mechanical properties,good biocompatibility,and outstanding processability.In particular,the crystalline region in silk fibroin contributes high strength and toughness.However,it is difficult to obtain the crystalline silk nanofibrils or nanosheets through top-down methods.The existing silk-derived components are mainly amorphous and sacrifice the delicate structure of the pristine silk.Herein,we report a gentle method to extract the crystalline silk nanosheet(SNS)from the degummed silk fibers.The crystalline SNS has seven strands ofβ-sheet nanocrystal layer and shows a thickness of 2.75 nm.It can assemble into a membrane via a vacuum filtration process and shows high transparency,excellent thermal stability,outstanding cytocompatibility,and efficient dye interception.Moreover,without external stimuli,the crystalline SNS is capable of reversibly self-assembling to well-organized microfibers.The crystalline SNS is not only a new member of silk fibroin derivatives,but also a promising assemblable unit for versatile applications.We anticipate this work will provide a new insight into the construction and applications of diverse two-dimensional(2D)functional silk materials.

关 键 词：silk fibroin hierarchical structure top-down exfoliation crystalline nanosheet reversible self-assembly 

分 类 号：TB3[一般工业技术—材料科学与工程]