Abstract Flexible and printable memristors are emerging as transformative platforms at the intersection of materials science, electronics, and neuromorphic computing. By integrating mechanical flexibility with resistive-switching functionality, these devices open new opportunities for low-power, flexible, and next-generation wearable electronics. This review provides a comprehensive overview of recent advances in flexible memristors, highlighting progress in flexible substrates, scalable fabrication techniques, novel functional materials, and their diverse application domains. Key materials include polymer dielectrics, two-dimensional (2D) materials, metal oxides on flexible substrates, and organic–inorganic hybrids, engineered into thin films, nanosheets, nanorods, and nanocrystals through vapour deposition and solution-based routes. We discuss how material composition, deposition methodology, interface engineering, and nanostructuring approaches govern key performance metrics, including
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endurance, retention, switching speed, and mechanical robustness under bending or stretching. The evolution of switching mechanisms, from filamentary conduction to interface-mediated processes and ion migration, is contextualized with the emerging applications, including neuromorphic computing, flexible memory arrays, logic circuits, and bio-interfaced electronics, such as artificial skin and wearable health monitors. Further, we address the challenges associated with the practical applications of the flexible memristive devices and discuss the future directions of research that can be pivotal in shaping the future of intelligent, responsive electronics.

Intermittent hydrogen gas inhalation has the potential to prevent UVA-induced photoaging by reducing oxidative stress, although the underlying molecular mechanisms remain unclear. Additionally, alternatives to animal experiments are recommended for studies not primarily focused on pathogenesis. This study aimed to evaluate the preventive effects of hydrogen gas on UVA-induced photoaging using a short-term invitro system with artificial skin. Artificial skin was irradiated with UVA at 0, 7, or 10.5 J/cm2/day and incubated for 1 day in a CO2 incubator with or without 1.3% hydrogen gas. This cycle was repeated three times, followed by one-day incubation. Transcriptomic and histological analyses were then performed. UVA at 7 J/cm2/day induced minimal epidermal morphological changes but marked photoaging-related transcriptomic alterations, whereas 10.5 J/cm2/day caused epidermal hypoplasia with excessive apoptosis and only limited transcriptomic changes. In comparisons between the 7 J/cm2/day groups with and without hydrogen, hydrogen modulated UVA-induced biological processes and signaling pathways, including the NRF2-mediated and the NFκB1-RelA-mediated responses, and suppressed the p53-mediated senescence pathway. This study demonstrated that photoaging-related transcriptomic changes were detectable in artificial skin under a relatively low UVA dose (7 J/cm2/day; total 21 J/cm2) with minimal histological alterations. Furthermore, hydrogen may have a protective effect against UVA-induced cellular stress and senescence, via diffusion through the skin surface, suggesting its potential effectiveness in preventing photoaging. This study provides preliminary evidence that may contribute to the development of future translational research on the utility of molecular hydrogen in UVA-induced photoaging.

Abstract Human somatosensation arises from one-dimensional (1D) nerve bundles that compactly transmit multimodal sensory signals along linear pathways, where proprioceptive and tactile receptors are intricately coordinated to enable precise perception and adaptive motor control. Inspired by this biological architecture, we develop a fiber-based artificial somatosensory system that reproduces such multimodal coordination within a single 1D structure. The fiber form factor can be freely distributed and routed throughout three-dimensional (3D) robotic or anatomical frameworks, emulating the connectivity and compactness of biological nerves. Fabricated via a thermal drawing process, these multimaterial fibers achieve high throughput and precise microstructural control over meter-scale lengths while integrating an optical strain-sensing unit (artificial muscle spindle) and an electrical pressure-sensing unit (artificial tactile receptor) in a single body. This configuration enables simultaneous yet decoupled detection of strain and pressure, providing multimodal feedback analogous to natural somatosensation. When embedded in robotic limbs, our multisensory fibers reproduce coordinated proprioceptive and tactile feedback during manipulation and locomotion, closely mimicking the functional integration of biological mechanoreceptors. This work establishes a scalable and biologically inspired route toward 1D fiber-based 3D artificial somatosensation, offering new opportunities for enhanced robotic feedback, human-machine interfaces, and next-generation artificial skin technologies.

Investigation of a Blue Light LED Device to Suppress Wound Pathogens Using a Collagen-Based Synthetic Skin Model

Fully functional hair follicle organ regeneration using organ-inductive potential stem cells with an accessory mesenchymal cell population in an in vitro culture system.

Bioprocessing and Functional Characterization of Hibiscus Hamabo Root Culture Bioactives: Antioxidant and Moisturizing Effects with Surfactin-Enhanced Penetration in Artificial Skin Models.

Skin healing often results in scarring or pathological conditions like keloids due to abnormal cell proliferation. These outcomes are attributed to abnormal proliferation or functional defects in skin cells. Hydrogels, mimicking the extracellular matrix, can guide hierarchical cell alignment for improved regeneration. Inspired by egg white’s foaming ability, we engineered a bilayer hydrogel dressing: a porous dermis layer via whipped egg white and a dense epidermis layer crosslinked with calcium. The artificial egg white skin (EWS) was tested in in vitro cell culture and in vivo application on mouse wounds. RNA sequencing explored the specific mechanism of EWS on cells. EWS features a multistage macroporous structure mimicking skin’s longitudinal mechanical performance. This migration inducive property of egg white facilitates directional migration and allows for the vertical stacking of keratinocytes and fibroblasts. The collaboration of cells enhances expression of positive chemokines and growth factors, shortening inflammation reaction and improving wound healing. Transcriptome sequencing reveals a substantial up-regulation of genes related to cell cycle and metabolism. EWS offers a cost-effective and efficient platform for biomimetic skin dressing and shows potential for other applications in regenerative medicine.

Retraction of "3D Protein-Based Bilayer Artificial Skin for the Guided Scarless Healing of Third-Degree Burn Wounds in Vivo".

Tactile perception plays a vital role in artificial finger pulp skin, especially in regions responsible for grasping and touching tasks, where precise sensing of deformation position and applied force is critical. Conventional demodulation methods often fail to fully leverage temporal correlations in data during the pressing process, limiting the accuracy of tactile demodulation. To address this, we propose a tactile sensing system based on quasi-distributed Fiber Bragg Gratings (FBGs) integrated into artificial finger pulp skin, along with a two-stage hybrid LSTM-Transformer neural network (TSH-LTNN) to jointly reconstruct pressing position and force. The network trains a temporal demodulation model by constructing possible data variations over three consecutive time steps, where the LSTM captures short-term continuity, the Transformer extracts long-range dependencies, and an adaptive fusion module integrates their complementary features. Experimental results show that the proposed model outperforms existing methods. In the 0-30 mm pressing range and 0-14.71 N force range, the mean absolute error (MAE) for position prediction is 0.2331 mm (R2 = 0.9971), and for force prediction, it is 0.303 N (R2 = 0.9829). Compared to the Random Forest model, the TSH-LTNN achieves a 2.34% improvement in position R2 and a 66.06% reduction in MAE. For force prediction, it demonstrates a 2.48% improvement in R2 and a 31.94% reduction in MAE. These results confirm that the proposed system offers precise, stable, and real-time pressure-state demodulation, with strong potential for high-precision haptic feedback applications.

Organic optoelectronic devices demonstrate immense potential in flexible displays, wearable electronics, and artificial skin, needing precise light-field and morphology management strategies to further improve their opto-electric performance. Nanoimprint lithography (NIL) has emerged as a high-resolution, high-efficiency, and low-cost patterning technique that mechanically transferring micro/nanoscale patterns from a template to a substrate to significantly enhance the optoelectronic performance through the precise creation of advanced light-management structures, combined with additional solid-state stacking morphology. This review systematically summarizes recent advances in NIL technology for organic optoelectronics. It begins with an introduction to the fundamental principles, main process variants (thermal, ultraviolet, and electrochemical NIL), as well as key technical issues. Subsequently, through specific applications in organic light-emitting diodes, organic solar cells, and organic field-effect transistors, it highlights the exceptional capabilities of NIL to enhance device performance by controlling crystallization and creating functional micro/nanostructuring. Specific advantages include enabling high-efficiency light management to overcome efficiency bottlenecks, facilitating low-cost, high-throughput manufacturing for industrialization, full compatibility with flexible substrates for emerging applications, enabling multifunctional integration and novel device architectures, and tailoring material microstructures and properties advance fundamental research. Finally, we discuss the remaining challenges and future prospects of NIL in integrated organic optoelectronic systems.

Less lethal projectile wound pattern identification using synthetic skin.

Background/Objectives: Topical treatment of cutaneous tuberculosis (CTB) requires reliable models to evaluate dermal drug release and diffusion, particularly for fixed-dose combinations (FDCs) with contrasting physicochemical properties. Human skin remains the reference standard but poses ethical, logistical, and reproducibility challenges. This study investigated the suitability of Strat-M® synthetic membranes as an alternative to human skin for assessing the simultaneous release and diffusion of clofazimine (CFZ) and pyrazinamide (PZA) from a topical FDC, and aimed to develop an optimized dermal emulsion using a Quality-by-Design (QbD)-informed formulation development tool. Methods: Self-emulsifying dermal emulsions containing CFZ and PZA were developed following QbD principles. Preformulation studies included drug solubility screening, oil phase selection, and pseudoternary phase diagram construction to identify stable emulsion regions. Formulations were characterized for droplet size, polydispersity index, zeta potential, viscosity, self-emulsification efficiency, and thermodynamic stability. Eight stable emulsions were identified, of which four were selected for in vitro drug release studies. The peppermint oil-based emulsion (PPO415) was further evaluated in comparative diffusion studies using Strat-M® membranes and ex vivo human skin (Caucasian and African). Results: PPO415 demonstrated favorable physicochemical properties, including high CFZ solubility, uniform droplet distribution, and suitability for dermal application. Comparative diffusion studies showed that Strat-M® underestimated the partitioning of lipophilic CFZ while overestimating the diffusion of hydrophilic PZA relative to human skin. These differences were attributed to compositional and structural disparities between synthetic membranes and biological skin. Conclusions: Strat-M® membranes show potential as a reproducible and ethical in vitro screening tool during early-stage formulation development for topical FDCs. However, ex vivo human skin remains essential for accurately predicting dermal drug distribution and therapeutic performance.

Background Venous leg ulcers are a common health problem for patients suffering from chronic venous insufficiency. Despite the notable advances in prevention and treatment made during the past years, up to a third of VLUs still display significantly delayed or no healing, with an insufficient response to mainline therapy alone. Aim This literature review aims to showcase the available treatment methods of venous leg ulcers, their individual and, when possible, comparative effectiveness, as well as identify which patients would likely benefit from additional solutions and adjuncts, in order to improve healing outcomes and reduce recurrence. Materials and Methods This article reviews the existing literature on venous leg ulcer treatment. Original studies, reviews, and studies available in the Cochrane, PubMed, and Google Scholar databases were included. The literature review and article selection process concluded in November 2025. Results Data pooled from the available studies shows that compression therapy, paired with suitable lifestyle interventions, remains the backbone of venous leg ulcer treatment. Adjuncts such as pentoxifylline, wound dressings, and artificial skin grafts display a sufficiently well-established effectiveness in increasing healing effectiveness. The lack of high-quality studies comparing individual products and substances within each wider category largely limits the potential to formulate specific recommendations and should be viewed as a potential area for future research. Conclusions While the findings back up the effectiveness of the standard treatment for venous leg ulcers, consisting primarily of compression therapy, available adjuncts show potential to improve outcomes, particularly among patients with a high risk of delayed healing or those dealing with frequent recurrences, and should be considered when the appropriate indications are present.

High-performance flexible tactile pressure sensor via MXene/Bi/tissue paper composite films for wearable electronics.

ABSTRACT The development of artificial electronic skin (e‐skin) that replicates the tactile sensing capabilities of human skin offers transformative potential for intelligent robotics and next‐generation wearable technologies. However, achieving compact, energy‐efficient integration of multiple sensing modalities within a single platform remains a significant challenge. Here, we present a bio‐inspired microchanneled e‐skin, functioning as a microchanneled triboelectric nanogenerator (MC‐TENG), that enables self‐powered, multimodal sensing in a unified framework. The device incorporates a conducting gel synthesized by dispersing graphene nanoplatelets (GNPs) into a polyvinyl alcohol/sodium nitrate matrix (PVA/NaNO 3 /GNPs), resulting in enhanced mechanical robustness with tensile and compressive strengths of 0.41 and 2.8 MPa, respectively. The MC‐TENG generates an output current of approximately 5.6 µA, with voltage and power outputs reaching 39.9 V and 0.44 mW, sufficient for operating low‐power electronics and detecting human motion. Fabricated e‐skin demonstrates excellent pressure, temperature, and stiffness sensitivity of ~1.81 V/kPa, ~42.7 mV/K, and ~7.43 × 10 −6 V/Nm −1 , respectively. Further, integration with a robotic arm enables functionalities such as object recognition, texture identification, and thermal sensing. This scalable, low‐cost, and self‐sustaining e‐skin platform represents a promising route toward more perceptive and interactive robotic systems, as well as advanced human‐machine interfaces.

Introduction: Cervical necrotizing fasciitis (CNF) is a rare, but serious condition that can develop as a result of an odontogenic infection spreading into the deep fascial planes of the neck. The infection is associated with significant morbidity and mortality due to septic shock and consequent multiple organ failure. Early diagnosis is of paramount importance with immediate surgical management and appropriate antimicrobial therapy being key in obtaining a good outcome. Patients require aggressive surgical resection necrotic tissues which can affect form and function in the head and neck. Surgeons dealing with cervical necrotizing fasciitis should be skilled in tracheostomy, have good knowledge of head and neck anatomy, able to deal with fasciitis around neck vessels, and the ability to reconstruction the neck as needed. Case Report: A case of CNF affecting a 31-year-old male, who was treated with multiple rapid surgical debridements, intravenous antibiotics, and tracheostomy, is presented. Transfer to a neighboring unit was needed due to concern of potential spread to the mediastinum necessitating cardio-thoracic intervention. After further debridements, artificial skin grafting and reconstruction were carried, and the patient was successfully discharged from the hospital. Conclusion: Cervical necrotizing fasciitis is a relatively uncommon, rapidly progressive, and often life-threatening soft tissue infection. Early diagnosis, aggressive antibiotic, and surgical treatment play a vital role in the management of the disease. In patients with resultant skin or soft tissue defects, advanced reconstructive techniques are needed to close resultant defects.

The repair of deep skin defects involving subcutaneous tissue urgently requires vascularized skin substitutes capable of providing immediate blood perfusion. However, existing engineering strategies struggle to construct multi-level vascular networks in vitro. This study aimed to develop a multi-layered skin substitute with both biomimetic structure and physiological function, incorporating a perfusable "small-micro" hierarchical vascular system. We employed a composite coaxial-extrusion bioprinting strategy. First, a composite bioink of 2% sodium alginate/5% gelatin methacryloyl (GelMA) was formulated and evaluated for its printability and biocompatibility. Subsequently, using an ionic-photo dual-crosslinking coaxial printing technique, we fabricated subcutaneous small vessels with controllable dimensions and adequate mechanical properties. Finally, these small vessels were integrated with an extrusion-bioprinted dermal microvascular network and an epidermal layer to form a complete "small-micro" vascular pathway. This multi-layered construct was designed to mimic the stratified characteristics of natural skin. In vitro functional experiments confirmed that the epidermis possesses excellent barrier function, and the subcutaneous small vessels demonstrated effective drug molecule delivery capability. The dual-crosslinking coaxial printing and composite manufacturing strategy proposed in this proof-of-concept study successfully achieved the construction of vascularized skin with a hierarchical tubular structure, offering a new solution with clinical translation potential for treating full-thickness skin defects.  

A dramatic increase in skin related disorders is apparent on account of the extensive use of synthetic skin whitening agents (antimelanogenesis). Pollution and occupational hazards have further led to the increased melanin synthesis (hyperpigmentation) amongst the exposed population. Consequently, herbal and/or its combination with the synthetic skin whitening agents have eroded share of existing skin whitening cosmetic formulations. Current research was aimed at the rational development of a cost-effective plant-based antimelanogenic formulation containing phytoactives as a promising option for skin whitening. Total 112 phytoconstituents were screened for antimelanogenic activity using in silico docking protocol against the enzyme tyrosinase responsible for melanogenesis. The binding energy score, π–π, charge and hydrogen interactions were utilized to identify ‘lead’ molecules. The PASS online tool was utilized to forecast the skin whitening activity for selected phytochemicals. Subsequently, selected plant extracts were formulated into nanoemulsion and evaluated for antimelanogenic activity in B16F10 cell lines. The in silico data revealed that, kuwanol, sesamolin, rosmarinic acid, astragalin, folic acid, riboflavin, sesaminol, albanol, sesamin, rutin, moracin-O holds potential as antimelanogenic leads. The developed nanoemulsion was significantly better than standard marketed gel, even at a lesser concentration (P<0.05). The potential antimelanogenic activity of nanoemulsion was evident from the B16F10 cell lines. Virtual screening of phytoconstituents has been demonstrated to be a powerful tool in the discovery of probable skin whitening leads. The rationally developed skin whitening nanoemulsion has been found to be superior over the marketed formulation. Thus, developed skin whitening phytonanoemulsion holds great translational promise to clinical studies.

Flexible mechanoluminescence (ML) elastomers show significant potential for next-generation wearable electronics, artificial skin, advanced sensing, and human-machine interaction. However, their broader application has been hindered by challenges such as restricted emission wavelengths, inadequate repeatability, insufficient cyclic stability, and poor self-recovery. Here, we report an innovative and high-performance solar-blind ultraviolet ML elastomer by combining commercial polydimethylsiloxane (PDMS) and newly fabricated Sr3(BO3)2:Pr3+ phosphors, capable of generating intense ultraviolet-C (UVC) ML peaked at 272 nm under mechanical stimulation. The composite elastomer exhibits exceptional repeatability and cyclic stability, maintaining detectable UVC emission over 10,000 continuous stretching cycles (power intensity at the 1st cycle is ~6.2 mW m-2). It also demonstrates rapid and efficient self-recovery behavior, restoring 43.2% of its initial intensity within 1 s and 90.2% after 24 h. Combined experimental and theoretical analyses reveal that interfacial triboelectrification, involving electron transfer from the phosphor to the PDMS matrix, leads to the observed UVC ML emission. Leveraging the solar-blind nature and high photon energy of UVC light, we further demonstrate the feasibility of self-powered photonics applications. This work not only offers novel insights into the design of advanced UVC ML systems but also provides "power-free" solutions for important applications where UVC photons are essential, such as outdoor optical tagging and microbial sterilization.

Humans could sensitively perceive and identify objects through dense mechanoreceptors distributed on the skin of curved fingertips. Inspired by this biological structure, this study presents a general conformal integration method for flexible tactile sensors on curved fingertip surfaces. By adopting a spherical partition design and an inverse mode auxiliary layering process, it ensures the uniform distribution of stress at different curvatures. The sensor adopts a 3 × 3 tactile array configuration, replicating the 3D curved surface distribution of human mechanoreceptors. By analyzing multi-point outputs, the sensor reconstructs contact pressure gradients and infers the softness or stiffness of touched objects, thereby realizing both structural and functional bionics. These sensors exhibit excellent linearity within 0-100 kPa (sensitivity ≈ 36.86 kPa-1), fast response (2 ms), and outstanding durability (signal decay of only 1.94% after 30,000 cycles). It is worth noting that this conformal tactile fingertip integration method not only exhibits uniform responses at each unit, but also has the preload-free advantage, and then performs well in pulse detection and hardness discrimination. This work provides a novel bioinspired pathway for conformal integration of tactile sensors, enabling artificial skins and robotic fingertips with human-like tactile perception.