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Inexpensive, lightweight, flexible yet robust circuit boards are essential for applications such as wearable electronics. According to a recent paper posted on the arXiv preprint server, these electronics could be printed on flexible circuits made from bacterial cultures used to make a popular fermented black tea drink called kombucha. there is.
As we previously reported, making kombucha only requires combining tea and sugar with a kombucha culture known as SCOBY (a symbiotic culture of bacteria and yeast), aka the “mother” – tea mushrooms, tea fungi, Or Manchurian mushrooms. Similar to a sourdough starter. SCOBY is a firm, gel-like collection of cellulose fibers (biofilm) thanks to active bacteria in culture that create the perfect breeding ground for yeast and bacteria to thrive. Dissolve the sugar in hot, non-chlorinated water and soak your favorite tea leaves in the hot sugar water before discarding.
Once the tea has cooled, add the SCOBY and pour the whole into a sterile beaker or jar. Then cover the beaker or jar with paper towels or gauze to keep insects away and let it sit for 2-3 weeks. Homemade kombucha is ready. The new “daughter” SCOBY floats right above the liquid (technically known in this form as a pellicle).
Beyond the popularity of beverages, kombucha cultures show promise as useful biomaterials. Degradable SCOBY-based clothing, shoes, or handbags. In 2021, scientists at the Massachusetts Institute of Technology and Imperial College London will develop a new class of robust biosensors that could in the future be used as biosensors to help purify water or detect damage to “smart” packaging. I created a “living material”. In an experiment last year by researchers at Montana Tech University (MTU) and Arizona State University (ASU), membranes grown from kombucha cultures were more likely to form biofilms (important in water filtration) than membranes currently available commercially. It was shown to be excellent in preventing
“Today, kombucha is emerging as a promising candidate to produce sustainable textiles for use as eco-friendly bio-wearables,” said co-author Andrew Adamatsky of the University of the West of England, Bristol, New Scientist. “We see dry and hopefully living kombucha mats being incorporated into smart wearables that extend the functionality of clothing and gadgets. We propose to develop a smart eco-wearable that is
Andrew Adamatsky et al., 2023
Adamatsky previously published a 2021 paper demonstrating that living kombucha mats exhibit dynamic electrical activity and stimulus responses, and a paper last year describing the development of a bacteria-reactive glove that acts as a living electronic sensing device. co-authored. Inspired by the potential of kombucha mats for wearable electronics, he and his latest co-authors have demonstrated that electronic circuits can be printed onto dry SCOBY his mats.
The team used commercially available kombucha bacteria to grow the mats and allowed the cultures to air dry on plastic or paper at room temperature. The mat is not easy to tear and can be soaked in water for several days without breaking easily. One of our test mats survived oven temperatures up to 200° C (392° F), but the mat will burn if exposed to an open flame.Adamatsky othersThey were able to print conductive polymer circuits onto dry kombucha mats using an aerosol jet printer, and have also successfully tested an alternative method of 3D printing circuits from a conductive polyester/copper mixture. I even managed to attach a small LED to the circuit using silver spiked epoxy glue that still worked after repeated bending and stretching.
According to Adamatsky others, unlike the live kombucha mats he used previously, the dry SCOBY mats are non-conductive and trap electrical currents in printed circuits. Inexpensive and flexible. Potential applications include, for example, wearable heart rate monitors and other kombucha-based devices. “Future research will involve printing highly functional circuits that can detect and possibly recognize mechanical, optical, and chemical stimuli,” the authors conclude.
DOIs: arXiv [preprint]2023. 10.48550/arXiv.2302.03984 (About DOI).
