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bioRxiv · 10.1101/853044

Viscoelastic properties of ECM-rich embryonic microenvironments

Akos, Z.·Isai, D. G.·Rajasingh, S.·Kosa, E.·Ghazvini, S.·Dhar, P.·Czirok, A.
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Abstract

The material properties of tissues and their mechanical state is an important factor during development, disease, regenerative medicine and tissue engineering. Here we describe a microrheological measurement technique utilizing aggregates of microinjected ferromagnetic nickel particles to probe the viscoelastic properties of embryonic tissues. Quail embryos were cultured in a plastic incubator chamber located at the center of two pairs of crossed electromagnets. We estimate the Youngs modulus of the ECM-rich region separating the mesoderm and endoderm in Hamburger Hamilton stage 6-10 quail embryos as 300{+/-}100 Pa. We found a pronounced viscoelastic behavior consistent with a Zener (standard generalized solid) model. The viscoelastic response is about 45% of the total response, with a characteristic relaxation time of 1.3 sec.

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Akos, Z., Isai, D. G., Rajasingh, S., Kosa, E., Ghazvini, S., Dhar, P., Czirok, A.. 2019-11-23. Viscoelastic properties of ECM-rich embryonic microenvironments. https://doi.org/10.1101/853044

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