Gelatin and Tannic Acid Based Iongels for Muscle Activity Recording and Stimulation Electrodes

AGUZIN, ANA; LUQUE, GISELA C.; RONCO, LUDMILA I.; DEL AGUA, ISABEL ; GUZMÁN-GONZÁLEZ, GREGORIO; MARCHIORI, BASTIEN; GUGLIOTTA, AGUSTINA; TOMÉ, LILIANA C. ; GUGLIOTTA, LUIS M.; MECERREYES, DAVID; MINARI, ROQUE J.

ACS Biomaterials Science and Engineering

American Chemical Society

Año: 2022 vol. 8 p. 2598 - 2609

2373-9878

Iongels are soft ionic conducting materials, usuallycomposed of polymer networks swollen with ionic liquids (ILs),which are being investigated for applications ranging from energyto bioelectronics. The employment of iongels in bioelectronicdevices such as bioelectrodes or body sensors has been limited bythe lack of biocompatibility of the ILs and/or polymer matrices. Inthis work, we present iongels prepared from solely biocompatiblematerials: (i) a biobased polymer network containing tannic acidas a cross-linker in a gelatin matrix and (ii) three differentbiocompatible cholinium carboxylate ionic liquids. The resultingiongels areflexible and elastic with Young‘s modulus between 11.3and 28.9 kPa. The morphology of the iongels is based on a dualpolymer network system formed by both chemical bonding due tothe reaction of the gelatin’s amines with the polyphenol units and physical interactions between the tannic acid and the gelatin.These biocompatible iongels presented high ionic conductivity values, from 0.003 and up to 0.015 S·cm−1at room temperature.Furthermore, they showed excellent performance as a conducting gel in electrodes for electromyography and electrocardiogramrecording as well as muscle stimulation.