Natural, Biocompatible, and 3D-Printable Gelatin Eutectogels Reinforced with Tannic Acid Coated Cellulose Nanocrystals for Sensitive Strain Sensors

PABLO A. MERCADAL; MARCELO ROMERO; MARIA DEL MAR MONTESINOS; JUAN PABLO REAL; MATIAS L. PICCHIO; AGUSTÍN GONZÁLEZ

ACS APPLIED ELECTRONIC MATERIALS

AMERICAN CHEMICAL SOCIETY (ACS)

Año: 2023 vol. 5 p. 2184 - 2184

onic gels from eutectic mixtures are attracting extensive interest in bioelectronicsowing to their nonvolatile nature, low cost, and inherently high ionic conductivity.Biodegradable electronics made of biopolymers envisage a promising future in thisfield, but unfortunately, they often feature poor mechanics. Herein, we exploredtannic acid-decorated cellulose nanocrystals (TA@CNC) as dynamic nanofillers ofbiocompatible eutectogels based on gelatin and a eutectic mixture composed ofcholine chloride and ethylene glycol (ethaline). Small concentrations of TA@CNC(up to 12 wt%) allow increasing by two-fold the strength (30 kPa) and stretchability(180%) of the eutectogels while improving their ionic conductivity (105 mS·m-1). Thereversible physical network of the protein and multiple hydrogen bonding interactionswith tannic acid endow these eutectogels with good self-adhesiveness, suitable gelto-sol transition for 3D printing, and recyclability. We further used the cellulosenanocompo