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bioRxiv · 10.1101/2024.01.21.576528

Functionalising the electrical properties of Kombucha zoogleal mats for biosensing applications

Abstract

Kombucha is a type of tea that is fermented using yeast and bacteria. During this process, a film made of cellulose is produced. This film has unique properties such as biodegradability, flexibility, shape conformability, and ability to self-grow, as well as be produced across customised scales. In our previous studies, we demonstrated that Kombucha mats exhibit electrical activity represented by spikes of electrical potential. We propose using microbial fermentation as a method for in situ functionalisation to modulate the electroactive nature of Kombucha cellulose mats, where graphene and zeolite were used for the functionalisation. We subjected the pure and functionalised Kombucha mats to mechanical stimulation by applying different weights and geometries. Our experiments demonstrated that Kombucha mats functionalised with graphene and zeolite exhibit memfractive properties and respond to load by producing distinctive spiking patterns. Our findings present incredible opportunities for the in situ development of functionalised hybrid materials with sensing, computing, and memory capabilities. These materials can self-assemble and self-grow after fusing their living and synthetic components. This study contributes to an emergent area of research on bioelectronic sensing and hybrid living materials, opening up exciting opportunities for use in smart wearables, diagnostics, health monitoring and energy harvesting applications.

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Nikolaidou, A., Chiolerio, A., Dehshibi, M. M., Adamatzky, A.. 2024-01-24. Functionalising the electrical properties of Kombucha zoogleal mats for biosensing applications. https://doi.org/10.1101/2024.01.21.576528

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