Observation of spider silk by femtosecond pulse laser second harmonic generation microscopy

Abstract

An asymmetric β‐sheet structure of spider silk is said to induce optical second harmonic generation. In this paper, using an in‐house nonscanning type femtosecond pulse laser second harmonic generation microscope, we characterized the behavior of the β‐sheet of spider silk under an applied external force. The orientation of the β‐sheets was more unidirectional when the silk was extended. One of the origins of the high mechanical strength of the dragline is suggested to be the physical arrangement of its β‐sheets.

Photo-elasticity of silk fibroin harnessing whispering gallery modes

“…The use of external stimulations (i.e. high voltage poling) for tuning the formation and orientation of β-sheets emerges as a promising approach for developing optical biomaterials with high polarizability properties, for linear or non-linear 43 optical operations. The β-sheet dominated refractivity and photo-elasticity of Silk II can be further fruitfully exploited in the development of planar or fiber guided wave structures, characterized by exotically high birefringence 38 , for use in polarization selective passive and active photonic devices; also, the elastic and inelastic light scattering properties of Silk II deserve further attention.…”

Unraveling the Mechanical Property Decrease of Electrospun Spider Silk: A Molecular Dynamics Simulation Study

“…42 We divided the spider silk into crystalline and amorphous regions because the crystalline region is composed of several beta sheets, and the amorphous region is composed of beta sheets (30%), coils (70%), and helices (<0.1%). 43 Based on the main secondary conformational differences, we assumed that the changes in the hydrogen bonds affected the mechanical properties differently. 15,36 Figure 4(d), (e), and (f) shows a scattering plot graph of the Young's modulus, UTS, and toughness versus the hydrogen bond, respectively.…”