Microrheology of non mulberry silk varieties by optical tweezer and video microscopy based techniques

Yogesha; Raghu A; Siddaraju G N; G Subramanya; Somashekar R; Sharath Ananthamurthy

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arXiv · 1102.3035

Microrheology of non mulberry silk varieties by optical tweezer and video microscopy based techniques

Yogesha·Raghu A·Siddaraju G N·G Subramanya·Somashekar R·Sharath Ananthamurthy

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Abstract

We have carried out a comparative study of the microrheological properties of silk fibroin solutions formed from a variety of silks indigenous to the Indian subcontinent. We present the measured viscoelastic moduli of Tasar silk fibroin solution using both a single and dual optical tweezer at 0.16% and 0.25% (w/v). The bandwidth of the measurements carried out using optical tweezers is extended down to the lower frequency regime by a video microscopy measurement. Further, we have measured the viscoelastic moduli of Eri and Muga varieties of silk fibroin solutions at a higher concentration (1.00% w/v) limiting the tool of measurement to video microscopy, as the reduced optical transparencies of these solutions at higher concentration preclude an optical tweezer based investigation. The choice of a higher concentration of fibroin solution of the latter silk varieties is so as to enable a comparison of the shear moduli obtained from optical methods with their corresponding fibre stiffness obtained from wide angle X-ray scattering data. We report a correlation between the microstructure and microrheological parameters of these silk varieties for the concentration of fibroin solutions studied.

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Yogesha, Raghu A, Siddaraju G N, G Subramanya, Somashekar R, Sharath Ananthamurthy. 2011-02-15. Microrheology of non mulberry silk varieties by optical tweezer and video microscopy based techniques. https://arxiv.org/abs/1102.3035

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