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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. 

The rapid proliferation of the Internet of Things (IoT) necessitates compact, sustainable, and autonomous energy sources for distributed electronic devices. Microbial fuel cells (MFCs) offer an eco‐friendly alternative by converting organic matter into electrical energy using living micro‐organisms. However, their integration into microsystems faces significant challenges, including incompatibility with microfabrication, fragile anode materials, low electrical conductivity, and compromised microbial viability. Here, this study introduces a microscale biobattery platform integrating laser powder bed fusion‐fabricated 316L stainless steel anodes with resilient, spore‐formingBacillus subtilisbiocatalysts. The 3D‐printed gyroid scaffolds provide high surface‐to‐volume ratios, submillimeter porosity, and tunable roughness, enhancing microbial colonization and electron transfer. The stainless steel ensures mechanical robustness, chemical stability, and superior conductivity.Bacillus subtilisspores withstand harsh conditions, enabling prolonged storage and rapid, on‐demand activation. The biobattery produces 130 μW of power, exceeding conventional microscale MFCs, with exceptional reuse stability. A stack of six biobatteries achieves nearly 1 mW, successfully powering a 3.2‐inch thin‐film transistor liquid crystal display via capacitor‐assisted energy buffering, demonstrating practical applicability. This scalable, biologically resilient, and fabrication‐compatible solution advances autonomous electronic systems for IoT applications.