Piezoelectric materials provide a unique platform for bioelectronic interfaces, enabling dynamic sensing and electroactive therapies through bidirectional transduction between biomechanical and bioelectrical signals. However, the development of bioresorbable piezoelectric materials that combine high functional performance with mechanical compliance remains a critical challenge for seamless integration with soft biological tissues, while eliminating the need for retrieval surgeries and long-term material retention. Here, we report a bioresorbable, flexible piezoelectric composite composed of Rochelle salt (RS) crystals embedded within poly(L-lactic acid) (PLLA) nanofibers. Fabricated via electrospinning and uniaxial compression, centimeter-scale biodegradable nanofiber films are achieved, exhibiting excellent effective piezoelectric coefficient of 43.1 pC N−1 and piezoelectric voltage coefficient of 1909.2 mV m N−1, surpassing the piezoelectric performance of previously reported biodegradable flexible materials. Ultrasound-driven scaffold devices derived from these bioresorbable piezoelectric materials markedly enhance sciatic nerve regeneration in rodents. Additionally, a biodegradable piezoelectric strain sensor enables wireless, real-time monitoring of intestinal motility, facilitating diagnosis of colonic dysfunction. Together, these findings establish a prominent materials paradigm for biodegradable piezoelectric electronics, offering a versatile platform for bioelectronic applications in regenerative medicine, neuromodulation, and physiological monitoring. Bioresorbable piezoelectric materials are key for bioelectronic–tissue integration but remain challenging to realize. Here, the authors develop flexible Rochelle salt/PLLA nanofibers that enable effective nerve regeneration and wireless monitoring of intestinal motility.

Critical-sized bone defects pose substantial clinical challenges, requiring both regenerative and diagnostic strategies for effective treatment. Here, we report a biodegradable, multifunctional cranial device based on three-dimensional printing. The device integrates a self-electrified scaffold based on a transient zinc-molybdenum battery and an impedance sensor for simultaneous electrical stimulation and continuous assessment of bone healing. The beneficial effects of electrical cues are attributed to elevated calcium ion influx, reactive oxygen species signaling, and up-regulated osteogenesis-related genes. In a rodent cranial defect model, the device promotes osteogenesis while enabling dynamic tracking of early tissue regeneration through impedance measurements. The increase in impedance is associated with enhanced collagen deposition and matrix mineralization. By uniting therapeutic stimulation with in situ monitoring, this work offers a platform for intelligent bone repair with broad potential in regenerative medicine.

Emulating biological vision requires aqueous-compatible neuromorphic devices that perform light sensing and complex synaptic dynamics. Organic electrochemical transistors (OECTs), capable of converting ionic signals into electronic current via electrochemical doping, closely mimic biological synaptic signaling. This capability distinguishes them from traditional electronic synapses, which rely purely on electron transport. However, prior OECTs typically require multiple components for bidirectional synaptic potentiation and depression, limiting integration and scalability. Here, we present an ambipolar all-polymer bulk heterojunction vertical OECT that enables light-tunable bidirectional synaptic plasticity while functioning stably in aqueous electrolytes at low operating voltages (≤ 0.4 V). Through photon-modulated electrochemical doping and ambipolar charge transport, the device integrates light sensing, bidirectional synaptic plasticity, and sustained memory (over 130 min) in a single device, mimicking the dual-polarity signaling of retinal bipolar cells. This design allows the transistor to read, write, and erase signals without complex external circuitry. We further demonstrate a vertically integrated optoelectronic synaptic array capable of image recording, selective optical erasure, rewriting, and background denoising, highlighting the feasibility of both global and localized reprogramming. This scalable, light-controlled organic synapse unlocks high-density, biocompatible circuits for artificial retinas and neuromorphic vision.

Lactate is a key metabolite and prognostic biomarker, reflecting oxygen delivery, cellular demand, and mitochondrial function. Current clinical lactate monitoring, however, relies on intermittent blood sampling, limiting localized interrogation, dynamic tracking and early intervention in critical care. Here, we report a bioresorbable and flexible electrochemical sensor for continuous deep-tissue lactate monitoring. By leveraging a previously unreported enzyme-assisted proton-intercalation mechanism, we establish a unique electrochemical sensing interface that enables high-performance lactate detection entirely with biodegradable materials. Integrated with a wireless module, the device enables in vivo real-time recording with excellent sensitivity and stable operation over clinically relevant timescales (> 10 days), without requiring secondary surgeries for device retrieval. The sensor robustly captures organ-specific lactate dynamics during hypoxia and epileptic seizures. Notably, we identify that increases in pericardial lactate precede systemic changes detected by conventional monitoring in septic shock, providing a prominent marker for early warning and timely intervention. Pericardial lactate-guided treatment markedly improves hemodynamic stability and prevents septic shock within the monitoring window. This work enables paradigm-shifting strategies for bioresorbable, implantable sensors that monitor vital metabolites in real time, supporting early diagnosis, guided intervention and improved outcomes in intensive care.

This paper proposes a millimeter-sized, high-sensitivity, wide-dynamic-range 16-channel electrochemical sensing SoC with integrated thin-film organic electrochemical transistor (OECT), utilizing ultrasonic wireless power and backscatter wireless communication technology. A bidirectional current conveyor and resistor (CC+R) potentiostat with duty-cycle control is introduced to minimize the static current consumption by reducing the duty cycle of the OECT amplification process. Additionally, the programmable gain amplifier's (PGA's) sampling capacitor is repurposed for small current-to-voltage conversion, extending the measurement range with minimal overhead. The system further integrates an active full-wave rectifier with backscatter amplitude modulation, supporting a wide range of received pulse amplitudes, variable time-of-flight (ToF), and tunable ultrasound frequencies. The design is fabricated using a 180 nm CMOS process. Experimental result features a sensing current measurement range of 184 dB, with a minimum current noise of 1.25 pA${}_{\text{rms}}$. The power consumption of the single-channel system is 16.3 $\mu W$. The design was validated for the detection of inflammatory factors, achieving a limit of detection (LoD) as low as 0.1 pM and the linearity with $R^{2}$ greater than 0.95.

Mechanical stimulation as a form of physical therapy plays a crucial role in regulating cellular behavior and promoting tissue regeneration. It can influence cell proliferation, differentiation, migration and extracellular matrix deposition, thereby providing a powerful biophysical cue in regenerative medicine. The implementation of precisely controllable mechanical stimulation relies on efficient and reliable tool platforms that can deliver defined magnitudes, frequencies, directions and temporal patterns of force, while maintaining high reproducibility and safety in biological environments. For mechanical stimulation of cells and injured tissues, a variety of materials as well as devices with distinct force outputs, such as stretchable elastic substrates, microfluidic shear systems and mechano-active scaffolds have been designed to meet diverse experimental and therapeutic requirements. Moreover, functional materials integrated with magnetic, acoustic and optical modalities are also been developed to establish remote mechanical stimulation systems, enabling spatiotemporally programmable interventions even in deep or delicate tissues. This review summarizes recent advances of the in vitro and in vivo strategies that leverage mechanical stimulation in regenerative medicine, along with its regulatory effects on regenerative processes in neural, skeletal, muscular and other tissues. Finally, the major challenges and prospects regarding materials and devices for mechanical stimulation in tissue therapy are discussed.

Peripheral nerve injury often leads to severe and persistent motor and sensory deficits, thereby markedly reducing quality of life. Peripheral nerve interfaces offer opportunities to facilitate functional restoration by interrogating neural activity and delivering electrical therapy. However, existing devices are typically not designed for long-term monitoring of injured nerves and are fabricated from non-degradable materials that require surgical removal. Here we present a temporally biosynchronized, physically transient and flexible peripheral nerve interface that enables stable monitoring of neural activity throughout the post-injury recovery process. Integrated with machine-learning-based decoding, the interface achieves excellent motor intention recognition using peripheral nerve signals in a rodent sciatic nerve injury model, outperforming signals recorded from the primary motor cortex. Moreover, the device enables continuous tracking of nerve regeneration and supports bidirectional signal transmission, providing a foundation for closed-loop rehabilitation. This work establishes a transient and biomimetic peripheral nerve interface with the potential to advance neuroregeneration monitoring and adaptive neurorehabilitation strategies.

Exploring the coding mechanisms of the nervous system and their associated functions holds great value in neuroscience research. Specifically, monitoring deep-brain neuronal activities with high specificity and minimal invasiveness is crucial. In this study, the development and application of a wireless photometric probe system is presented to monitor calcium (Ca2+) dynamics in the hippocampus during seizure events in freely moving mice. The probe integrates thin-film, microscale optoelectronic devices, including a micro light-emitting diode (micro-LED) and a photo detector, to excite and capture fluorescent emissions of the genetically encoded Ca2+ indicator (GCaMP). Wavelength-selective optical designs minimize the spectral crosstalk and optimize the detection of green fluorescence signals. Additionally, a portable, miniaturized wireless circuit module powers the devices and remotely transmits data. In vitro experiments validate the probe's capability to detect fluorescence signals in both ambient and aqueous environments, while in vivo experiments reveal its efficacy in capturing Ca2+ dynamics during seizure occurrences provoked by electrical stimulations as well as drug administrations in the hippocampus of behaving mice. The wireless photometric probe system developed here offers a promising tool for neuroscience research, particularly in studying complex behaviors and disease models in freely moving animals.

The growing threat of refractory wound has created imperative need for the exploration of novel repair materials and therapeutic strategies. The disrupted endogenous electric fields in refractory wound may prolong the healing process. Hence, apply exogenous electrical stimulation to reestablish endogenous electric fields may be a promising way for refractory wounds treatment. Herein, a photo-driven electronic skin consist of p-type Si thinfilm and near-infrared light was developed. This electronic skin could electrically modulate the intracellular calcium oscillation and significantly promote the fibroblasts' adhesion, proliferation and migration. Specifically, the average spreading area achieved 1.23 times higher than plane group after 24 h seeding. The cell proliferation quantity was 117 % higher than plane group after 3 days' PES treatment. As for cell migration, the complete wound closure was observed at 48 h in all the PES treatment group compared to 76.47 +/- 1.23 coverage area in control group. Furthermore, it demonstrated rapid closure rate of a full-thickness circular diabetic skin defects with photoelectric stimulation (PES) derived from electronic skin, the wound was almost healed at 14 days' treatment. Furthermore, the expression level of pro-inflammation factors of IL-1 beta and TNF-alpha were reduced. Proteomic analysis showed that the metabolism process, the cellular processes of transport and catabolism, cell motility were remarkably promoted after PES treatment. The transport and catabolism process may regulate by mTOR signal pathway, and the increased cellular processes of cell motility may result of actomyosin contractility. This photo-driven electronic skin not only provided a facile therapeutic strategy and theoretical basis for refractory wound, but also provided a novel insight into potential mechanism underlying electrical stimulation promoting tissue repair.

Electrocatalytic and photocatalytic hydrogen evolution reaction (HER) via water-splitting play a significant role in solving environmental and energy crisis. Two-dimensional (2D) nanomaterials are regarded as promising materials in the electrocatalytic and photocatalytic HER field due to its large surface area, good hydrophilicity and brilliant electronic conductivity. However, several drawbacks, such as low crystalline quality, low productivity and limited intrinsic active sites, restrict its industrial applications. Herein, a facile and green one-step method is proposed to prepare Ni nanoparticles coated by carbon in the 2D carbon nanosheet (2D Ni/C-m) through molten salt (NaCl)-facilitated pyrolysis method. Benefit from the excellent electrical conductivity, large surface area, holey and the synergistic effect between composition and structure of the prepared 2D Ni/C-m catalyst. The prepared large surface areas of the 2D Ni/C-0.75 catalyst show much better electrocatalytic and photocatalytic HER activities among Ni/C-m and Ni samples. 2D Ni/C-0.75 exhibits HER potential of -110 mV and -375 mV at - 10mA cm- 2 and -200mA cm- 2, compare to that of Pt/C (eta 200 = -339 mV). 2D Ni/C-0.75 also exhibits photocatalytic hydrogen speed of 78 mu mol h- 1 with Eosin Y as photosensitizer. Additionally, 2D Ni/ C-0.75 shows wonderful stability in electro/photocatalytic HER. These results provide a new insight into fabricating new Ni-based catalysts for electro/photo-catalytic hydrogen evolution.

Realizing precise recording with large populations of neurons has been a long-standing goal in developing next-generation brain-machine interfaces(BMIs)[1,2].Specifically,flexible electro-corticography(ECoG)devices placed on the cerebral cortex provide a nonpenetrating means to measure population-level coordinated neural activities across wide cortical areas,and have been success-fully applied for speech synthesis,motor decoding,and seizure localization[3].

Monitoring the early-stage healing of severe traumatic nerve injuries is essential to gather physiological and pathological information for timely interventions and optimal clinical outcomes. Traditional diagnostic methods relying on physical examinations, imaging tools, and intraoperative electrophysiological testing present great challenges in continuous and remote monitoring. While implantable peripheral nerve interfaces provide direct access to nerve fibers for precise interrogation and modulation, conventional non-degradable designs pose limited utilization in nerve injury rehabilitation. Here, we introduce a biodegradable and restorative neural interface for wireless real-time tracking and recovery of long-gap nerve injuries. Leveraging machine learning techniques, this electronic platform deciphers nerve recovery status and identifies traumatic neuroma formation at the early phase, enabling timely intervention and significantly improved therapeutic outcomes. The biodegradable nature of the device eliminates the need for retrieval procedures, reducing infection risks and secondary tissue damage. This research sheds light on bioresorbable multifunctional peripheral nerve interfaces for probing neuropathic injuries, offering vital information for early diagnosis and therapeutic intervention.

Non-invasive, real-time, and continuous monitoring of trace amounts of glucose in near-neutral biofluids is significant for the daily care and treatment of diabetic patients or people with suboptimal health status. Despite improved sensing performance with novel low-dimensional materials or porous structures in various enzymatic and non-enzymatic electrochemical glucose sensors, they still suffer from high cost, poor long-term stability, and performance fluctuations in varied temperature and pH. This work synergistically combines an Au-modified porous laser-induced graphene (LIG) gate electrode with an organic electrochemical transistor (OECT) to create a flexible non-enzymatic glucose sensor. The resulting OECT-based non-enzymatic glucose sensor exhibits significantly enhanced sensitivity in near-neutral biofluids, the limit of detection (LOD) (0.08 μM in pH = 7.4), excellent stability over time (degradation of ∼10 % in 180 days) and against temperature changes (30 °C-40 °C), self-pH calibration capabilities, and uncompromised sensing performance with shrinking sizes. The highly consistent laser patterning technique and in situ galvanic reduction process for electrode modifications not only provide a simple yet versatile approach to creating low-cost, compact sensing platforms for precise and real-time sweat glucose measurements but also support scalable production, allowing the correlation study of key biomarkers in sweat and blood.

Precise control of light-induced electrical signals at the biotic-abiotic interface remains a central challenge in advancing next-generation bioelectronic systems. In particular, achieving bidirectional signal modulation is essential for effective neural interface applications. Here, a spatially resolved, bidirectional photoelectric response at the silicon (Si) membrane-solution interface, induced by laser illumination is presented. Notably, a clear reversal in signal polarity between the illuminated regions (bright zones) and adjacent non-illuminated areas (dark zones) is observed. This signal orientation can be dynamically tuned by adjusting the light spot position and tailoring interfacial properties. To understand the underlying mechanism, the author systematically examined how various experimental parameters influence photoelectric behavior. These include the choice of adhesive, substrate conductivity (conductive vs insulating), boundary conditions (fixed vs free edges), and membrane geometry (e.g., grids and rectangles). These results reveal a cooperative effect between intrinsic charge conservation in the Si membrane and capacitive coupling at the interface. Moreover, in vivo studies show that integrating a conductive substrate beneath the Si membrane significantly enhances the modulation of sciatic nerve activity. Together, these findings define a new framework for light-responsive bioelectronic interfaces and point toward their broad utility in bioelectronic and neuromodulation applications.

The pursuit of precisely recording and localizing neural activities in brain cortical regions drives the development of advanced electrocorticography (ECoG) devices. Remarkable progress has led to the emergence of micro-ECoG (μECoG) devices with sub-millimeter resolutions. This review presents the current research status, development directions, potential innovations and applications of high-density, high-throughput μECoG devices. First, we summarize the challenges associated with accurately recording single or multiple neurons using existing μECoG devices, including passive multielectrode and active transistor arrays. Second, we focus on cutting-edge advancements in passive μECoG devices by discussing the design principles and fabrication strategies to optimize three key parameters: impedance, mechanical flexibility, and biocompatibility. Furthermore, recent findings highlight the need for further research and development in active transistor arrays, including silicon, metal oxide, and solution-gated transistors. These active transistor arrays have the potential to unlock the capabilities of high-density, high-throughput μECoG devices and overcome the limitations of passive multielectrode arrays. The review explores the potential innovations and applications of μECoG devices, showcasing their effectiveness for both brain science research and clinical applications.

Peripheral nerve injury (PNI) poses a significant public health issue, often leading to muscle atrophy and persistent neuropathic pain, which can drastically impact the quality of life for patients. Electrical stimulation represents an effective and non-pharmacological treatment to promote nerve regeneration. Yet, the postoperative application of electrical stimulation remains a challenge. Here, we propose a fully biodegradable, self-powered nerve guidance conduit (NGC) based on dissolvable zinc-molybdenum batteries. The conduit can offer topographic guidance for nerve regeneration and deliver sustained electrical cues between both ends of a transected nerve stump, extending beyond the surgical window. Schwann cell proliferation and adenosine triphosphate (ATP) production are enhanced by the introduction of the zinc-molybdenum batteries. In rodent models with 10-mm sciatic nerve damage, the device effectively enhances nerve regeneration and motor function recovery. This study offers innovative strategies for creating biodegradable and electroactive devices that hold important promise to optimize therapeutic outcomes for nerve regeneration.

Real-time detection of tissue oxygenation in the nervous system is crucial in neuroscience studies and clinical diagnostics. Complementary to blood oxygenation levels, the partial pressure of oxygen in brain tissue ( p_btO_2 ) plays a key role in regulating local neural activities and metabolism. Here we develop an implantable optoelectronic probe that wirelessly and continuously monitors p_btO_2 signals in the deep brain of freely moving rodents. The thin-film, microscale implant integrates a light-emitting diode and a photodetector, and is coated with an oxygen-sensitive phosphorescent film. Powered by a battery or an inductive coil, a miniaturized circuit is capable of recording and wirelessly transmitting p_btO_2 signals. The wireless micro-probe captures cerebral hypoxia states in mice in various scenarios, including altered inspired oxygen concentrations and acute ischaemia. In mouse models with seizures, the micro-probe associates temporal p_btO_2 variations in multiple brain regions with electrical stimulations applied to the hippocampus. Our probe and method offer important insights into neuroscience studies regarding neurometabolic coupling and pave the way for the clinical application of implantable wireless optoelectronic probes.

Noise-induced hearing loss (NIHL) often accompanies cochlear synaptopathy, which can be potentially reversed to restore hearing. However, there has been little success in achieving complete recovery of sensorineural deafness using nearly noninvasive middle ear drug delivery before. Here, we present a study demonstrating the efficacy of a middle ear delivery system employing brain-derived neurotrophic factor (BDNF)-poly-(dl-lactic acid-co-glycolic acid) (PLGA)-loaded hydrogel in reversing synaptopathy and restoring hearing function in a mouse model with NIHL. The mouse model achieved using the single noise exposure (NE, 115 dBL, 4 h) exhibited an average 20 dBL elevation of hearing thresholds with intact cochlear hair cells but a loss of ribbon synapses as the primary cause of hearing impairment. We developed a BDNF-PLGA-loaded thermosensitive hydrogel, which was administered via a single controllable injection into the tympanic cavity of noise-exposed mice, allowing its presence in the middle ear for a duration of 2 weeks. This intervention resulted in complete restoration of NIHL at frequencies of click, 4, 8, 16, and 32 kHz. Moreover, the cochlear ribbon synapses exhibited significant recovery, whereas other cochlear components (hair cells and auditory nerves) remained unchanged. Additionally, the cochlea of NE treated mice revealed activation of tropomyosin receptor kinase B (TRKB) signaling upon exposure to BDNF. These findings demonstrate a controllable and minimally invasive therapeutic approach that utilizes a BDNF-PLGA-loaded hydrogel to restore NIHL by specifically repairing cochlear synaptopathy. This tailored middle ear delivery system holds great promise for achieving ideal clinical outcomes in the treatment of NIHL and cochlear synaptopathy.

Implantable chemical sensors built with flexible and biodegradable materials exhibit immense potential for seamless integration with biological systems by matching the mechanical properties of soft tissues and eliminating device retraction procedures. Compared with conventional hospital-based blood tests, implantable chemical sensors have the capability to achieve real-time monitoring with high accuracy of important biomarkers such as metabolites, neurotransmitters, and proteins, offering valuable insights for clinical applications. These innovative sensors could provide essential information for preventive diagnosis and effective intervention. To date, despite extensive research on flexible and bioresorbable materials for implantable electronics, the development of chemical sensors has faced several challenges related to materials and device design, resulting in only a limited number of successful accomplishments. This review highlights recent advancements in implantable chemical sensors based on flexible and biodegradable materials, encompassing their sensing strategies, materials strategies, and geometric configurations. The following discussions focus on demonstrated detection of various objects including ions, small molecules, and a few examples of macromolecules using flexible and/or bioresorbable implantable chemical sensors. Finally, we will present current challenges and explore potential future directions.