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Abstract We introduce a groundbreaking proof-of-concept for a novel glucose monitoring transducing mechanism, marking the first demonstration of a spore-forming microbial whole-cell sensing platform. The approach uses selective and sensitive germination ofBacillus subtilisspores in response to glucose in potassium-rich bodily fluids such as sweat. As the rate of germination and the number of metabolically active germinating cells are directly proportional to glucose concentration, the electrogenic activity of these cells—manifested as electricity—serves as a self-powered transducing signal for glucose detection. Within a microengineered, paper-based microbial fuel cell (MFC), these electrical power outputs are measurable and can be visually displayed through a compact interface, providing real-time alerts. The dormant spores extend shelf-life, and the self-replicating bacteria ensure robustness. The MFC demonstrated a remarkable sensitivity of 2.246 µW·(log mM)⁻¹·cm⁻²to glucose concentrations ranging from 0.2 to 10 mM, with a notably lower limit of detection at ~0.07 mM. The sensor exhibited exceptional selectivity, accurately detecting glucose even in the presence of various interferents. Comparative analyses revealed that, unlike conventional enzymatic biosensors whose performance degrades significantly through time even when inactive, the spore-based MFC is stable for extended periods and promptly regains functionality when needed. This preliminary investigation indicates that the spore-forming microbial whole-cell sensing strategy holds considerable promise for efficient diabetes management and can be extended toward noninvasive wearable monitoring, overcoming critical challenges of current technologies and paving the way for advanced biosensing applications. 

This study presents a pioneering self-sustaining mechanism that exploits metabolic electron production from pre-loaded probiotics to power a vibrating capsule at a specific location in the gut. It is the first research to demonstrate the electrogenic properties of commercially available probiotics in a standard bacterial culture medium, Luria Broth (LB), and its application in generating vibration in a human stomach. The capsule is engineered with a miniature microbial fuel cell containing probiotics, an energy storage component (capacitor), a diode, and a vibrating motor. This assembly is enveloped in a Genipin-crosslinked mucoadhesive polymer to enhance adherence to the stomach lining and is further encapsulated within an acid-sensitive enteric coating to ensure selective dissolution in the stomach. This innovative approach heralds new possibilities for advanced gastrointestinal treatments by merging bio-electricity and biomechanics in a distinctive, patient-centric delivery system. 

This study unveils a pioneering yet straightforward approach to creating a moist-electric generator, using paper as the primary substrate and integrating bacterial endospores within it. The distribution of these endospores is meticulously regulated by the paper's inherent capillary action. The functional groups present on the endospores enhance moisture absorption and facilitate ion dissociation, resulting in a pronounced potential gradient driven by the variation in water content and endospore concentration. To augment water capture efficiency, a paper-based Janus layer combining hydrophobic and hydrophilic properties is applied atop the paper-based moist-electric generator. This dual-sided membrane excels in moisture condensation from the atmosphere and ensures unidirectional water transport to the generator, thus ensuring substantial electrical output even under low relative humidity conditions. This research not only addresses the challenges of power generation in wearable paper-based devices but also heralds new pathways for the development of autonomous, cost-effective, and eco-friendly energy solutions for wearable technologies. 

This study introduces a groundbreaking point-of-care (POC) system designed for antibiotic susceptibility testing (AST). At the heart of this innovation is the organic electrochemical transistor, a device that significantly amplifies the electrical signals arising from the redox activities and extracellular electron transfers of pathogens when exposed to antibiotics. This process involves electroactive reactions that either dope or de-dope the transistor's channel, leading to substantial changes in the current flow between the source and drain terminals. Furthermore, our system features an innovative integration with a paper substrate. This design decision significantly simplifies the handling of liquid bacterial cultures, making the process more straightforward and efficient. We have rigorously tested our sensing system using three well-known pathogens: Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli, exposing them to leading antibiotics to validate the system's effectiveness. 

This study presents a novel, simple method for biofilm cultivation and a combined electrical-electrochemical technique to efficiently gauge antibiotic effectiveness against biofilm-related infections.