Akos, ZsuzsaIsai, Dona GretaRajasingh, SheejaKosa, EdinaGhazvini, SabaDhar, PrajnaparamitaCzirok, Andras2020-11-102020-11-102020-08-31Akos, Z., Isai, D. G., Rajasingh, S., Kosa, E., Ghazvini, S., Dhar, P., & Czirok, A. (2020). Viscoelastic Properties of ECM-Rich Embryonic Microenvironments. Frontiers in cell and developmental biology, 8, 674. https://doi.org/10.3389/fcell.2020.00674https://hdl.handle.net/1808/30814This work is licensed under a Creative Commons Attribution 4.0 International License.The material properties of tissues and their mechanical state is an important factor in 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 found a pronounced viscoelastic behavior within the ECM-rich region separating the mesoderm and endoderm in Hamburger Hamilton stage 10 quail embryos, 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 s.© 2020 Akos, Isai, Rajasingh, Kosa, Ghazvini, Dhar and Czirok.http://creativecommons.org/licenses/by/4.0/ECMQuail embryoMicrorheologyElasticityYoung’s modulusZener solidMagneticNanorodsArticle10.3389/fcell.2020.00674PMC7487363openAccess