Periodic Reporting for period 1 - ELFO (Electronic Food: enabling edible electronic systems for biomedical and food monitoring applications)
Okres sprawozdawczy: 2020-09-01 do 2022-02-28
The newly minted field of edible electronics, while at an embryonic stage, is creating great scientific resonance by envisioning a technology which is safe for ingestion, environmentally friendly, cost-effective, and degraded within the body after performing its function, either digested or even metabolized. Yet there is no shared approach, and the field is currently unified only by the use of food-derived or edible synthetic functional materials. In order to help shape the field more consistently, the main ideas and perspectives that have been proposed in the recent past were critically curated, underlining what edible electronics is and will be in the future according to our vision. Long-term opportunities in terms of environmentally friendly smart technologies, remote healthcare monitoring, and the formidable challenges ahead were discussed, covering major issues with respect to safety, materials approval, processing, power supply, communication, and human body interaction. A key point in moving toward such a vision is a strong interdisciplinary cooperation, which was highly encouraged.
- Honey-Gated Complementary Organic Transistors and Circuits
Dielectrics are a critical functional element of transistors, often constituting their major volume. Yet, to date, there are only scarce examples of electrolytic food-based materials able to provide low-voltage operation of transistors at ambient conditions. In this context, a cost-effective and edible substance, honey, was proposed to be used as an electrolytic gate viscous dielectric in electrolyte-gated organic field-effect transistors (OFETs). Both
n- and p-type honey-gated OFETs (HGOFETs) were demonstrated, with distinctive features such as low voltage (<1 V) operation, long-term shelf life and operation stability in air, and compatibility with large-area fabrication processes, such as inkjet printing on edible tattoo-paper. Such complementary devices enable robust honey-based integrated logic circuits, exemplified by inverting logic gates and ring oscillators. A marked device responsivity to humidity provides promising opportunities for sensing applications, specifically, for moisture control of dried or dehydrated food.
- An Electrically Conductive Oleogel Paste for Edible Electronics
Edible electrical conductors fabricated with green methods and at a large scale and composed of food derivatives, ingestible in large amounts without risk for human health are needed. Here, conductive pastes made with materials with a high tolerable upper intake limit (≥mg kg−1 body weight per day) were proposed. Conductive oleogel composites, made with biodegradable and food-grade materials like natural waxes, oils, and activated carbon conductive fillers, were presented. The proposed pastes are compatible with manufacturing processes such as direct ink writing and thus are suitable for an industrial scale-up. These conductors are built without using solvents and with tunable electromechanical features and adhesion depending on the composition. They have antibacterial and hydrophobic properties so that they can be used in contact with food preventing contamination and preserving its organoleptic properties. As a proof-of-principle application, the edible conductive pastes were demonstrated to be effective edible contacts for food impedance analysis, to be integrated, for example, in smart fruit labels for ripening monitoring.
This work led also to a patent application (confidential).
2) An Electrically Conductive Oleogel Paste for Edible Electronics was demonstrated for the first time
Work is in progress on communication strategies and powering devices (eg edible batteries), as well as highly performing edible semiconductors and edible sensors. By the end of the project, two edible electronic systems demonstrators will be achieved: an edible smart pill (ELFO-Pill) and an edible food tag (ELFO-tag).