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Abstract For decades, science fiction has imagined electronic devices that spring to life on demand, function as programmed, and then vanish without a trace. Today, transient and bioresorbable electronics are making that vision a reality, sparking revolutionary progress in biomedicine, environmental stewardship, and hardware security. Yet one critical barrier remains: a fully transient power source with the same disappearing act. Microbial‐based biobatteries have emerged as strong contenders, harnessing the power of microorganisms—found virtually everywhere—as natural biocatalysts. However, toxicity and health risks have limited these systems to single‐use, often incinerable applications. Here, a transformative approach: a transient biobattery powered by commercially available probiotics that dissolves harmlessly is introduced, releasing only beneficial microbes. Fabricated on water‐soluble or pH‐responsive substrates, this biobattery capitalizes on a 15‐strain probiotic blend to generate electricity across diverse electrode materials. By manipulating device length or encapsulating it with pH‐sensitive polymers, power delivery can be fine‐tuned from 4 min up to over 100 min. A single module outputs 4 µW of power, 47 µA of current, and an open‐circuit voltage of 0.65 V. This groundbreaking design ushers in a new era of safe, effective transient bioenergy systems, opening unprecedented opportunities in biomedical implants, environmental sensors, and disposable electronics. 

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. 

Abstract Disposable wearable electronics are valuable for diagnostic and healthcare purposes, reducing maintenance needs and enabling broad accessibility. However, integrating a reliable power supply is crucial for their advancement, but conventional power sources present significant challenges. To address that issue, a novel paper‐based moist–electric generator is developed that harnesses ambient moisture for power generation. The device features gradients for functional groups and moisture adsorption and architecture of nanostructures within a disposable paper substrate. The nanoporous, gradient‐formed spore‐based biofilm and asymmetric electrode deposition enable sustained high‐efficiency power output. A Janus hydrophobic–hydrophilic paper layer enhances moisture harvesting, ensuring effective operation even in low‐humidity environments. This research reveals that the water adsorption gradient is crucial for performance under high humidity, whereas the functional group gradient is dominant under low humidity. The device delivers consistent performance across diverse conditions and flexibly conforms to various surfaces, making it ideal for wearable applications. Its eco‐friendly, cost‐effective, and disposable nature makes it a viable solution for widespread use with minimal environmental effects. This innovative approach overcomes the limitations of traditional power sources for wearable electronics, offering a sustainable solution for future disposable wearables. It significantly enhances personalized medicine through improved health monitoring and diagnostics. 

Abstract Papertronics introduce a sustainable, cost‐effective revolution in electronics, especially for the Internet of Things. This research overcomes the traditional challenges of paper's porosity, which has impeded electronic component fabrication and performance. A novel approach that harnesses paper's natural capillary action, combined with hydrophobic wax patterning, to achieve precise vertical integration of electronic components is introduced. This method marks a significant departure from conventional surface deposition techniques. This study demonstrates the successful creation of tunable resistors, capacitors, and field‐effect transistors, embedded within a single sheet of paper. Contrary to previous assumptions that impeded the use of paper, its rough and porous texture as a strategic advantage, facilitating the precise fabrication of intricate electronic components is leveraged. Machine learning algorithms play an important role in predicting and enhancing the performance of these papertronic components. This innovation facilitates the development of compact printed circuit boards with increased circuit density, enabling the integration of diverse analog and digital circuits in either single or multi‐layer paper formats. The resulting papertronic systems exceed performance benchmarks, offering eco‐friendly disposal through biodegradability or incineration. These breakthroughs establish papertronics as a feasible, eco‐friendly alternative in the electronics industry, permitting widespread adoption and continuous innovation in sustainable electronic solutions. 

Abstract Transient electronics, which can operate only for short‐lived applications and then be eco‐friendly disintegrated, create opportunities in environmental sensing, healthcare, and hardware security. Paper‐based electronics, or papertronics, recently have rapidly advanced the physically transient device platform because paper as a foundation offers an environmentally sustainable and cost‐effective option for those increasingly pervasive and fast‐updated single‐use applications. Paper‐based power supplies are indispensable to realize a fully papertronic paradigm and are a critical enabler of environmentally benign power solutions. Microbial fuel cells (MFCs) hold great potential as power sources for such green papertronic applications. This work reports the design, operation, and optimization of a high‐power papertronic MFC by biosynthesizing microbe‐mediated tin oxide nanoparticles (SnO₂NPs) on dormant Bacillus subtilis endospores. They form an electrical conduit that improves electron harvesting during the spore germination and power generation. The MFC is packaged in a sub‐microporous alginate to minimize the potential risk of bacteria leakage. Upon the introduction of water, the paper‐based MFC generates a significantly enhanced power density of 140 µW cm⁻², which is more than two orders of magnitude greater than their previously reported counterparts. Six MFCs connected in series generate more than sufficient power to run an on‐chip, light‐emitting diode. 

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.