Effect of incubation temperature on the self-assembly of regenerated silk fibroin: a study using AFM.
Understanding effect of temperature on the molecular self-assembly process will be helpful to unravel the structure-function relationship of biomolecule and to provide important information for the bottom-up approach to nanotechnology. In this work, the effect of incubation temperature on the secondary structures and morphological structures of regenerated silk fibroin (RSF) was systematically studied using atomic force microscopy and Fourier Transform infrared spectroscopy. The effect of incubation temperature on RSF self-assembly was dependent on RSF concentration. For the RSF solution with relatively low concentrations (15 μg/mL and 60 μg/mL), the increase of the incubation temperature mainly accelerated the formation and aggregation of antiparallel β-sheet protofibrils and decreased the formation of random coil protofilaments/globule-like molecules. For the RSF solution with relatively high concentrations (300 μg/mL and 1.5mg/mL), the increase of the incubation temperature mainly accelerated the formation and aggregation of antiparallel β-sheet RSF features (protofibrils and globule-like features) and decreased the formation of random coil bead-like features. This work implies that the morphology and conformation of biomacromolecules could be tuned by controlling the incubation temperature. Further, it will be beneficial to basic understanding of the nanoscale structure formation in different silk-based biomaterials.
National Engineering Research Center for Nanotechnology, Shanghai 200241, People's Republic of China. Electronic address: jianzhongpku@hotmail.com.
Jian
J
Zhong
Department of Medical Imaging, Jinan Military General Hospital, No. 25 Shifan Road, Jinan, Shandong Province, People's Republic of China.
Xunwei
X
Liu
National Engineering Research Center for Nanotechnology, Shanghai 200241, People's Republic of China.
Daixu
D
Wei
National Engineering Research Center for Nanotechnology, Shanghai 200241, People's Republic of China.
Juan
J
Yan
National Engineering Research Center for Nanotechnology, Shanghai 200241, People's Republic of China.
Ping
P
Wang
Department of Medical Imaging, Jinan Military General Hospital, No. 25 Shifan Road, Jinan, Shandong Province, People's Republic of China. Electronic address: cjr.sungang@vip.163.com.
Gang
G
Sun
National Engineering Research Center for Nanotechnology, Shanghai 200241, People's Republic of China; School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.
Dannong
D
He
D005349:Fibroins / Q000737:chemistry* / Q000648:ultrastructure; D018625:Microscopy, Atomic Force; D017433:Protein Structure, Secondary; D047011:Silk / Q000737:chemistry* / Q000648:ultrastructure; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature
D047011:Silk; D005349:Fibroins
Atomic force microscopy; Morphology; Regenerated silk fibroin; Secondary structure; Temperature