Wearable bioelectronics that adhere directly to the skin have broad applications. However, achieving optimal breathability remains a significant challenge because of sweat accumulation at the device-skin interface. Conventional approaches, such as porous structures, often limit the functional versatility of wearable bioelectronics. To address this gap, we propose a sweat-removable skin sticker (SRSS) with a hierarchical trichome-inspired channel architecture that rapidly removes sweat from the interface while maintaining robust skin adhesion. The SRSS was fabricated through a hybrid process, in which the trichome-inspired hierarchical microchannel architecture was created by direct ink writing (DIW), enabling the controlled deposition of viscous ink with high structural fidelity. Through the multi-level ribs design, the SRSS demonstrated an effective area-normalized horizontal water removal rate (25.6 ml/cm²/min) significantly higher than the human sweat secretion rate (0.38-2.85 × 10⁻³ ml/cm²/min)-approximately three orders of magnitude. This feature reduces sweat accumulation in wearable bioelectronics, thereby enhancing user comfort. Unlike conventional porous materials, the SRSS relies on channel based adhesive interface design that remains compatible with attached wearable bioelectronics, such as temperature sensors in real time. This work therefore presents a structurally engineered permeable bioadhesive interface for wearable bioelectronics.
Injectable bioelectronics offer a minimally invasive approach to peripheral nerve stimulation but remain limited by onboard energy storage and fragile leads. Here, we present SEED, a leadless, battery-free bioelectronic interface engineered for percutaneous delivery through a standard 14-gauge needle. SEED (Stimulating Electrode for Electroceutical Delivery) operates in the magnetoquasistatic regime using low-frequency (65 kilohertz) resonant inductive coupling, externalizing waveform generation and control, enabling programmable neuromodulation without onboard active electronics. A spiral-helix electrode geometry promotes longitudinal nerve engagement while limiting off-target field spread. Benchtop and ex vivo characterization demonstrates precise, programmable control of stimulation frequency, pulse width, and amplitude under physiologically relevant conditions. In vivo validation in a rat sciatic nerve model confirms frequency-locked motor responses and graded neural recruitment following percutaneous deployment. SEED exhibits strong radiopacity and acoustic contrast, supporting compatibility with ultrasound and computed tomography for image-guided neuromodulation. This platform provides a scalable pathway toward minimally invasive bioelectronic therapies.
Implantable bioelectronics are rapidly advancing towards multifunctional platforms capable of real-time monitoring and therapeutic intervention. However, designing implants with stable, long-term integration with soft, dynamic biological tissues, especially under strain or movement, is still challenging. Here we introduce a stretchable, strain-insensitive, wet-tissue-adhesive elastomer-hydrogel biphasic platform for cross-functional bioelectronics, enabling simultaneous physical sensing, chemical monitoring and neural modulation in vivo. This platform, termed ElHyX, features a molecularly integrated elastomer-hydrogel architecture, functionalized with conductive fillers to achieve mechanical compliance, robust electrical performance and strong tissue adhesion without the need for sutures or additional surface treatments. Using direct ink writing, we fabricated customizable ElHyX-based devices for in vivo electrocardiogram monitoring, glucose sensing and nerve stimulation. A closed-loop system for diabetic management in rats was also developed, where real-time biosignal detection autonomously triggered neuromodulation to regulate blood glucose levels. Overall, our findings establish ElHyX as a versatile, scalable platform for next-generation bioelectronics, capable of continuous physicochemical monitoring and autonomous therapeutic intervention in complex biological environments.
Poly(3,4-ethylenedioxythiophene) (PEDOT)-based polymers have emerged as the unrivaled standards for mixed ionic-electronic conduction, bridging the gap between rigid electronics and soft biological tissues. However, the long-term operational stability of PEDOT-based devices is frequently compromised by a critical material failure: the delamination of the polymer coating under electrochemical and mechanical stress. This interfacial instability is a fundamental challenge shared across broad electrochemical applications, from bioelectronics to energy storage and fuel cells, where active materials undergo recurrent volumetric oscillation. While extensive research has optimized PEDOT-based polymers' electrochemical performance, the underlying interfacial mechanics remain insufficiently addressed in the literature. This review reconciles these disparate findings by first dissecting the genesis of the interface, illustrating how specific fabrication histories dictate fundamental failure modes: the intrinsic "stress accumulation" driven by in situ electropolymerization versus the osmotic "rehydration shock" characteristic of ex situ solution processing. Against this mechanistic backdrop, we establish a systematic framework for interfacial engineering, categorizing state-of-the-art adhesion strategies into two distinct paradigms: Chemical Anchoring, which leverages composites, intermediate layers, and functionalized derivatives to engineer covalent bridges; and Physical Anchoring, which utilizes "inside-out" deposition or "outside-in" etching to maximize mechanical interlocking. Beyond synthesis, we critically evaluate the lack of standardization in adhesion metrics, surveying techniques from in vitro stress tests to in vivo functional validation. By synthesizing these disparate methodologies, we propose a 3-tier benchmarking guideline to standardize future comparative studies. With these guidelines, we aim to outline a trans-disciplinary roadmap for seaming the biotic-abiotic divide, ensuring the reliability of the next-generation bioelectronic interface.
Bioelectronics enables bidirectional transduction between biological and electronic signals, with organic electrochemical transistors (OECTs) emerging as a leading platform due to their volumetric doping, high transconductance, low-voltage operation, and compatibility with soft, aqueous environments. While conjugated polymers provide versatile and scalable device architectures, the performance and functionality of OECTs are fundamentally governed by interfacial processes. This review focuses on how the interface engineering-across electrolyte/channel, channel/electrode, and device/tissue interfaces-directly controls ion transport, charge injection, capacitance, and biocompatibility. We summarize recent advances showing that tailored interfacial design enables multifunctional applications, including high-accuracy biosensing, bio-synaptic emulation, and integrated neuromorphic computing. We further outline key strategies for engineering these interfaces to advance next-generation OECT-based bioelectronics, and conclude by discussing remaining challenges and future directions.
Minimally invasive delivery of bioelectronics is currently limited by the irreversibility of deployment, rendering device retrieval traumatic and hindering clinical translation. Here, for the first time, we introduce a novel thermoresponsive, reversible-actuating polymer (Trap) that enables both minimally invasive implantation and retrieval. Trap exhibits a mechanistically unique dual-crystalline competition between (110)-oriented low-entropy crystals and (100)-oriented high-entropy crystals. The competitive crystallization governs bidirectional, stress-free shape memory within a human-compatible window (10°C-37°C), enabling rapid (<3 s), fatigue-resistant, and large reversible strain (∼30.17%). The solid-solid switching between two nanocrystalline states provides a robust and tunable actuation mode, allowing Trap to transition reversibly between compact 1D and functional 2D/3D geometries without mechanical loading. This materials' innovation directly enables microinvasive deployment and retraction of Trap-based neural electrodes through the same small incision (∼5 mm), as well as autonomous helical self-assembly and thermal detachment on peripheral nerves, achieving stable electrophysiological interfacing over weeks to months. This work establishes a material-centered framework for reversible biointerfaces, resolving the conflict between surgical invasiveness and device retrievability.
Poly(3,4-ethylenedioxythiophene): polystyrene sulfonate (PEDOT: PSS), distinguished by its exceptional electrical conductivity, superior biocompatibility, and capacity for multifunctional integration, has emerged as a pivotal biomaterial at the nexus of biomedical engineering and flexible electronics. This review systematically elucidates the fundamental physicochemical attributes and charge transport mechanisms of PEDOT: PSS. It critically examines mainstream modification strategies-including solvent doping, surfactant engineering, nanocomposite formulation, and plasma treatment-providing deep insights into how these approaches govern the material's microstructure and macroscopic performance. Building on this foundation, we detail recent breakthroughs in frontier applications such as biosensing and real-time monitoring, electroceuticals, tissue engineering and regenerative medicine, smart targeted drug delivery, and self-powered wearable devices. Special emphasis is placed on the synergistic interplay among performance optimization, modification strategies, and clinical translation. Furthermore, the article offers a critical analysis of persistent challenges hindering clinical adoption, including long-term stability, biosafety, and batch-to-batch consistency. Finally, we outline future trajectories, such as counterion substitution, biomimetic interface functionalization, and intelligent closed-loop systems. This work aims to establish a robust theoretical and technical framework to accelerate the advanced research and broad deployment of PEDOT: PSS in biomedical contexts.
Continuous and real-time monitoring of the subtle spatio-temporal changes in human physiological states are essential for daily diagnosis and treatment. Additionally, the capacity for monitoring is frequently restricted by available materials and specific application contexts. Wearable Flexible Ultrasound Biosensors (WFUBs) can be comfortably applied to the human body and have the functions of continuous monitoring and interventional therapy. The review summarized recent advances in the way WFUBs acquire vital data from particular biological tissue, the structural design and material selection, including the substrate, electrical connection, electrode, and the material synthesis of biosensors. In addition, the aspects of performance improvement of WFUBs were summarized, and the applications of wearable ultrasound systems in health care, diagnostic imaging, and interventional therapy were further discussed. Finally, the challenges and future research directions in the field of next generation WFUBs were explored.
The intelligence of the human biological system is enabled by the highly distributed sensing receptors on soft skin that can distinguish various stimulations or environmental cues, thus establishing the fundamental logic of sensing and physiological regulation or response. To replicate biological perception, biohybrid systems integrating living organisms with electronics have been developed to sense environmental cues. However, current eukaryote-based biohybrids face slow growth, strict culture needs, and short lifespans, limiting real-world use. Here, we introduce fungi-based printable "Mycoelectronics" which are created by additive bioprinting of living fungal mycelium networks onto stretchable electronics, as a practical living thermoresponsive sensory platform. This mycoelectronics approach leverages fung's capabilities for rapid biological responsiveness, cultivability with exponential growth, stability and self-healing in ambient conditions, bioprintability for scalable manufacturing, and mechanical flexibility for seamless integration with soft electronics. We show that the thermal responsiveness of the fungal network arises from intrinsic cellular processes-specifically, heat-induced vacuole remodeling and fusion, which modulate ionic transport and thus the electrical conductivity of the mycelial cells and networks, enabling a rapid response. By bridging the gap between cell biology and soft electronics, the mycoelectronics device, with a living mycelial network, functions as a thermal sensation system with rapid response and intrinsic self-healing properties, autonomously restoring sensing capabilities after damage and establishing sensing pathways in hard-to-reach locations. Application demonstrations in environmental and agricultural monitoring and wearable sensing systems for humans and robots highlight the versatility of this living fungal sensor platform, suggesting promising opportunities in healthcare and the environment.
The mechanical mismatch between rigid clinical electrodes and soft biological tissues remains a primary bottleneck restricting the stability of long-term electrophysiological monitoring. Printable flexible thin-film electrodes offer a compelling solution by enabling additive, high-throughput patterning on flexible and stretchable substrates, thereby circumventing the reliance on vacuum environments and high-temperature processing typical of conventional microfabrication. This review synthesizes recent advances in functional inks, ranging from metals and carbon nanomaterials to conductive polymers and ionogels, together with high-resolution printing techniques. Addressing the critical challenge of interfacial failure in flexible devices, we explore engineering strategies to enhance adhesion at both electrode-substrate and electrode-tissue interfaces. Specifically, we analyze the pivotal roles of physical interlocking and chemical anchoring mechanisms in suppressing dynamic delamination and maintaining device integrity. Finally, the review highlights representative applications in wearable electronics, implantable systems, and emerging organoid interfaces, and outlines key translational challenges, including long-term stability and manufacturing reproducibility.
Owing to advancements in implantable bioelectronic devices, there has been an increase in demand for biocompatible energy sources with long-term electrochemical and mechanical stability. In this study, we present the fabrication of a flexible asymmetric supercapacitor (MXene//AC) based on two-dimensional Ti3C2Tx MXene nanosheets. The supercapacitor demonstrates excellent electrochemical performance with an areal capacitance of 66.43 mF cm-2, energy density of 13.2 Wh kg-1, and a high power density of 2300 W kg-1. The supercapacitor retained 95% capacitance after 5000 charge-discharge cycles and displayed negligible performance degradation under various bending angles, highlighting its mechanical suitability for wearable electronics. Density functional theory (DFT) analysis revealed that the metallic Ti-C backbone of Ti3C2Tx MXene and its O/F terminations work synergistically to enable rapid electron transport and reversible proton-coupled surface redox, supporting predominantly surface-controlled charge storage with a significant pseudocapacitive contribution. To complement device-level studies, we assessed the in vivo safety profile and antioxidant potential of Ti3C2Tx MXene nanosheets in Sprague-Dawley (SD) rats through acute dermal, subchronic oral, and subchronic intraperitoneal toxicity evaluations. Acute dermal exposure up to 100 mg kg-1 caused mild skin responses without necrosis, while subchronic administration for 28 days revealed no considerable abnormalities in biochemical parameters (alanine aminotransferase, aspartate aminotransferase, blood urea nitrogen, creatinine), inflammatory markers (IL-1β, IL-6), or oxidative stress biomarkers (malondialdehyde, glutathione). Histopathological evaluations confirmed the absence of structural damage or inflammation in vital organs. Additionally, MXene nanosheets demonstrated antioxidant activity by scavenging 2,2-azino-bis(3-ethyl)benzothiazoline-6-sulfonic acid free radicals in a dose-dependent manner, highlighting their potential to reduce oxidative stress in biomedical applications. Overall, this dual-focused study demonstrates that MXene nanosheets are not only highly effective for developing flexible, stable asymmetric supercapacitors but also exhibit favorable in vivo biocompatibility and antioxidant properties at the tested doses. These findings emphasize the potential of MXene-based materials as next-generation, fully biocompatible energy storage devices for advanced implantable bioelectronic systems.
The integration of molecular recognition and electronic charge transport within a single-material system is central to the development of bioelectronic interfaces. However, in hybrid bioelectronic systems, these functionalities are often governed by poorly defined structural features, making it difficult to establish clear structure-function relationships. Here, we develop a growth-regulated metallization strategy based on self-assembled DNA nanosheets, enabling the formation of ultrathin, laterally extended metal-nucleic acid hybrid structures. By introducing surface-extending DNA brushes, nanosheet growth is sterically regulated and kinetically controlled, with DNA brush spacing governing nanosheet evolution by modulating the competition between lateral expansion and vertical thickening, thereby defining a kinetically stabilized ultrathin regime. This growth mechanism yields ultrathin, laterally extended amorphous nanosheets across multiple metal surfaces. Within this growth-defined system, structural parameters including brush spacing and metal layer thickness can be systematically tuned to regulate molecular recognition and charge transport. For molecular recognition, probe spacing (i.e., DNA brush spacing) and nanosheet thickness jointly determine hybridization performance by regulating steric hindrance and interfacial accessibility, defining an optimal structural window. For charge transport, nanosheet thickness and compositional matching govern transport behavior: increasing thickness enhances electronic coupling and reduces activation barriers, consistent with hopping-dominated transport, while compositionally matched nanosheet/electrode systems exhibit the most efficient interfacial charge transfer. This combination of enhanced hybridization and efficient charge transport enables high-performance electrochemical biosensing. More broadly, this work establishes a growth-controlled strategy for defining structure-function relationships in metal-nucleic acid hybrid systems.
Extracellular vesicles (EVs) are increasingly recognized as programmable biologics with broad therapeutic potential across diverse diseases. However, their clinical translation is hindered by limited therapeutic efficiency due to poor target engagement and rapid clearance by the mononuclear phagocyte system, together with insufficient control over in vivo exposure profiles and release kinetics required for sustained, site-specific activity. This review summarizes recent advances aimed at overcoming these limitations, focusing on two complementary approaches. First, we discuss molecular engineering strategies of EVs to improve the intrinsic therapeutic potential. These include donor-cell engineering to molecularly regulate vesicle biogenesis and cargo sorting, and molecular-level chemical tailoring of native vesicles that stabilize membranes, enable selective cargo loading, or preserve vesicle identity. Second, we examine intelligent device-based technologies that improve EVs behavior in vivo by programming protection, retention, and controlled release. Functional hydrogels, bioelectronic interfaces, and microstructured carriers offer protection from degradation, couple release to disease-relevant cues, and enhance their accumulation in target tissues. We conclude by highlighting key mechanistic insights, persistent translational bottlenecks, and emerging opportunities for developing programmable and pathology-adaptive EV therapeutics. Together, these advances help establish a framework for transforming EVs from promising experimental biologics into precise, durable, and clinically scalable medicines. STATEMENT OF SIGNIFICANCE: Extracellular vesicles (EVs) are increasingly recognized as therapeutically relevant biologics, but their clinical translation remains limited by poor target-site accumulation, rapid systemic clearance, and insufficient control over in vivo exposure and release kinetics. This review addresses these barriers from a biomaterials perspective by integrating two complementary strategies: engineering the vesicle itself and engineering the delivery environment. Specifically, it discusses how donor-cell programming and molecular tailoring can improve EV composition, stability, and biological activity, while biomaterial- and device-based platforms such as hydrogels, bioelectronic interfaces, and microstructured carriers can enhance protection, local retention, and controlled release in vivo. By bridging EV biology with biomaterials-enabled delivery strategies, this review provides a unified framework for the development of programmable and pathology-adaptive EV therapeutics. The concepts summarized here are relevant to the design of next-generation biomaterial-assisted biologics with improved precision, durability, and translational potential.
Reliable, noninvasive monitoring of metabolic biomarkers using wearable biosensors remains a significant challenge, owing to the low and variable concentration of analytes in sweat. Herein, we report a hierarchical V2CTx-MXene@f-MWCNTs/Laser-Induced Graphene (LIG) hybrid architecture for the multiplexed and dynamically calibrated sweat sensing of glucose and β-hydroxybutyrate (HB). The synergistic integration of 2D MXene and 1D f-MWCNTs prevents MXene restacking, increases electron flow, and enhances the electroactive surface area, while the porous 3D LIG matrix provides a flexible, and conductive platform for wearable bioelectronics. The microfluidic-integrated V2CTx@f-MWCNTs nanocomposite-based patch sequentially detects glucose and HB while providing real-time pH and temperature calibration. The fabricated patch biosensor exhibits high sensitivities of 131.41 μA mM-1 cm-2 and 53.81 μA mM-1 cm-2 (glucose and HB), with low detection limits of 2 μM and 10 μM, respectively. Moreover, the HB sensor exhibits stable performance for more than 171 min of continuous operation. This multifunctional platform demonstrates excellent electrochemical performance, stability, and reproducibility and reliable on-body applicability, providing accurate metabolic health monitoring and advancing next-generation noninvasive bioelectronic platforms.
Natural structural tissues achieve exceptional performance through precisely aligned hierarchical architectures that extend across multiple length scales. However, realizing such multiscale long-range alignment in synthetic bulk hydrogels remains challenging because of the difficulty in constructing a uniformly dense and highly oriented structure that extends throughout the full bulk matrix. Here, we introduce a scalable and versatile Layer-by-Layer Shear Densification (LBSD) strategy that integrates flocculation-induced aggregation with shear-driven progressive alignment, precisely driving the architectural evolution toward compact and uniformly ordered lamellar structures across multiscales. The resulting poly(vinyl alcohol) (PVA) hydrogels with a hierarchical network exhibit a Herman's orientation factor of 0.91, surpassing previously reported values for bulk hydrogels. The structural orientation enables the hydrogel to exhibit excellent mechanical properties, including a tensile strength of 41.29 ± 2.10 MPa and toughness of 159.37 ± 28.15 MJ·m⁻³. To demonstrate the versatility, this strategy is further used to fabricate gelatin hydrogels, resulting in a 32-fold enhancement in toughness. Anisotropic thermal conductivity, another representative physical property originating from molecular-level alignment, is also demonstrated. This work establishes a generalizable technology for developing high-performance bulk polymeric materials through molecular-level engineering, offering substantial potential for applications in load-bearing components, bioelectronic devices, thermal management systems, etc.
High-density thin-film neural interfaces face persistent packaging challenges at the electrode-electronics interface, where conventional rigid connectors impose high insertion forces, strict alignment requirements, and limited reusability. We present E-Link (Elastomeric Link), a modular 256-channel mini-pedestal connector designed to facilitate simplified, user-friendly assembly through an insertion-free, alignment-tolerant interface utilizing an elastomeric conductive interposer and a compliant threaded compression mechanism. Finite element analysis and experimental validation confirm uniform contact stress across the 16 × 16 interconnect array. The system achieves stable electrical performance, exhibiting contact impedances of 0.3-0.4 kΩ, an RMS noise floor of 2.68 ± 0.46 μV, and a connection yield exceeding 97% over 100 mating cycles. The detachable architecture reduces chronic head-mounted mass from 6.6 g to 2.8 g while maintaining safe thermal operation (30.5 °C steady-state) under a full 20 kHz sampling bandwidth. Design analysis further indicates scalability toward 1024-channel integration within the same 25-mm-diameter footprint by leveraging fine-pitch elastomeric conductive pillars. This work provides a robust and scalable connection solution for high-density flexible neural interfaces with broad application for bioelectronics.
Deep peripheral nerve regeneration is hindered by inflammatory infection, neurotrophic factor deficiency, and slow axonal growth kinetics. Although multifunctional nerve guidance conduits (NGCs) have been developed, achieving spatiotemporally precise neuromodulation within deeply located neural tissues remains a significant challenge. Herein, we developed a nerve conduit fabricated with a gut metabolite indole-3-propionic acid (IPA)-functionalized and polydopamine-coated Au nanorod clusters (AuNR@PDA-IPA (API)) loaded on a parallel fiber film of PLGA, exhibiting NIR-II-responsiveness for spatiotemporally precise neuromodulation. API nanoclusters convert deep-penetrating NIR-II light (1064 nm wavelength) into deeply localized heat (∼42-43 °C), which noninvasively activates the transient receptor potential vanilloid 1 (TRPV1) channel in Schwann cells (SCs). This activation triggers Ca2+ influx and membrane depolarization, promoting neurotrophic expression. Concurrently, NIR-II irradiation directly modulated the release of neuroprotective IPA from the API platform through an on-off switching mechanism. Meanwhile, IPA combined with PDA potently scavenged reactive oxygen species (ROS), suppressed NF-κB activation, and promoted M2 polarization of macrophages, thereby reshaping the neuroregenerative microenvironment. The in vitro and in vivo results demonstrate that API-functionalized conduit enhances VEGF-driven angiogenesis and activates SCs to upregulate the expression of neurotrophic factors (BDNF, NGF) and glial-specific proteins (S100, GFAPs). By orchestrated tripartite regulation of the "anti-inflammatory-angiogenic-neuroregenerative" system, the conduit enabled robust axonal regrowth, remyelination, and functional recovery in peripheral nerve defects, offering a transformative strategy for the repair of deeply located neural tissues. This work presents a noninvasive bioelectronic paradigm that merges spatiotemporal photothermal neuromodulation with immune metabolic reprogramming for precision neural reconstruction.
Epidermal ionic skins act as promising adaptable interfaces for bioelectronics, but they often struggle to simultaneously maintain softness, breathability, adhesion, and conductivity across both dry and aquatic environments. Here, we introduce an amphibious ionic skin engineered by integrating a hydrophobic star-shaped ionic liquid telomer as a bulky solvent within an amphiphilic linear poly(ionic liquid) network. The viscous four-arm telomers are dynamically interlocked within the entangled matrix, facilitating robust water-resistant self-adhesion and self-compliance. Meanwhile, the amphiphilic network provides efficient water-permeable channels, ensuring superior moisture breathability in ambient conditions. Compared to conventional small-molecule-based ionic gels, our ionic skin exhibits high underwater stability due to the restricted leaching of the bulky telomeric species. When fabricated into ultrathin film electrodes, the material enables the acquisition of high-fidelity electrophysiological signals in diverse environments, ranging from dry skin to fully submerged states. This topological network design provides a new strategy for developing environment-adaptive skin-like iontronic devices.
Endogenous electric fields (EFs) are essential for tissue regeneration but are diminished under hyperglycemia conditions, thereby impeding diabetic wound healing. Here, we report a biodegradable, glucose-powered electronic fabric bandage (GEB) that restores wound-edge electrical fields and enables closed-loop wound healing. To avoid compromising clinical applicability, we integrated all components into a soft, lightweight, and breathable bandage design to replace the traditional bulky electrical stimulator design. We also show the universal glucose-powered electricity generation and therapeutic functions of the electronic bandage across species and organs in diabetic wound models. In diabetic mouse wounds, porcine skin defects, and intestinal injury, the bandage uses endogenous glucose for power generation, thereby reducing local glucose levels and restoring the endogenous EF that guided cell migration, reprogrammed macrophage polarization, and promoted angiogenesis, to accelerate wound healing. These findings should establish an "endogenous glucose-powered symbiotic bioelectronics" paradigm for next-generation bioelectronic medicine.
Wearable flexible sensors have emerged as a cornerstone of next-generation bioelectronics, enabling skin-conformal, continuous, and high-fidelity monitoring of cardiovascular diseases (CVDs). This review elucidates the structure-function relationships that govern sensing performance, highlighting how material innovation, structure engineering, and device architectures synergistically balance sensitivity, mechanical robustness, and biocompatibility. Key cardiovascular physiological signals, including electrical, mechanical, hemodynamic, and biochemical modalities, are systematically summarized and correlated with representative sensing mechanisms such as piezoresistive, capacitive, triboelectric, electrochemical, and optical transduction. The integration of machine learning (ML) and data-driven modeling is further discussed, highlighting its potential to enable personalized diagnostics, multimodal fusion, and adaptive prediction of cardiovascular risks. Despite substantial progress, critical challenges remain in long-term operational stability, scalable manufacturing, cross-population generalizability, and clinical validation. To address these limitations, a unified design paradigm integrating materials engineering, multimodal sensing strategies, and algorithmic intelligence is proposed. This review aims to guide the development of next-generation wearable platforms that are not only mechanically compliant and functionally robust but also algorithmically interpretable and clinically translatable, laying the groundwork for intelligent, reliable, and precision-oriented CVD monitoring systems.