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Updated: Aug 24, 2026

Viscoelastic Characterization of Soft Tissue-Mimicking Gelatin Phantoms using Indentation and Magnetic Resonance Elastography
Published on: May 10, 2022
An interpretation of amphoteric gel hardness variation through potential and hardness measurement
Hirohisa Tamagawa1, Fumio Nogata, Kazuyuki Yagasaki
1Department of Human and Information Systems, Faculty of Engineering, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan. tmgwhrhs@cc.gifu-u.ac.jp
Abstract:
The hardness variation of amphoteric gel according to the surrounding solution conditions is quite unique. It hardens and softens reversibly regardless of its molecular network density. But this has been understood merely qualitatively. For the purpose of elucidation of the details of its behavior, we performed quantitative potential and hardness measurements on it. We observed the constant potential of amphoteric gels, approximately -60 mV, regardless of their swelling ratio and hardness. Such observations can be interpreted as the maintenance of the constant charge density of *COO- for any amphoteric gel, and they are further interpreted as intermolecular salt-linkage formation/disruption dominating the hardness of amphoteric gels.

