Nanoscale optical and structural characterisation of silk

Meguya Ryu; Reo Honda; Adrian Cernescu; Arturas Vailionis; Armandas Balcytis; Jitraporn Vongsvivut; Jing-Liang Li; Denver P. Linklater; Elena P. Ivanova; Vygantas Mizeikis; Mark J. Tobin; Junko Morikawa; Saulius Juodkazis

arXiv · 1902.02688

Nanoscale optical and structural characterisation of silk

Meguya Ryu·Reo Honda·Adrian Cernescu·Arturas Vailionis·Armandas Balcytis·Jitraporn Vongsvivut·Jing-Liang Li·Denver P. Linklater·Elena P. Ivanova·Vygantas Mizeikis·Mark J. Tobin·Junko Morikawa·Saulius Juodkazis

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Abstract

Background: Nanoscale composition of silk defining its unique properties via a hierarchical structural anisotropy has to be analysed at the highest spatial resolution of tens-of-nanometers corresponding to the size of fibrils made of b-sheets, which are the crystalline building blocks of silk. Results: Nanoscale optical and structural properties of silk have been measured from 100-nm thick longitudinal slices of silk fibers with ~10 nm resolution, the highest so far. Optical sub-wavelength resolution in hyperspectral mapping of absorbance and molecular orientation were carried out for comparison at IR wavelengths 2-10 micrometers using synchrotron radiation. Conclusion: Reliable distinction of transmission changes by only 1-2% due to anisotropy of amide bands was obtained from nano-thin slices of silk.

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Meguya Ryu, Reo Honda, Adrian Cernescu, Arturas Vailionis, Armandas Balcytis, Jitraporn Vongsvivut, Jing-Liang Li, Denver P. Linklater, Elena P. Ivanova, Vygantas Mizeikis, Mark J. Tobin, Junko Morikawa, Saulius Juodkazis. 2019-02-07. Nanoscale optical and structural characterisation of silk. https://arxiv.org/abs/1902.02688

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