Self-Assembled Tamoxifen-Selective Fluorescent Nanomaterials Driven by Molecular Structural Similarity.

Most supramolecular systems were discovered by using a trial-and-error approach, leading to numerous synthetic efforts to obtain optimal supramolecular building blocks for selective guest encapsulation. Here, we report a simple coassembly strategy for preparing tamoxifen-selective supramolecular nanomaterials in an aqueous solution. The synthetic amphiphile molecule, 1,1,2,2-tetraphenylethylene (TPE), promotes large tamoxifen aggregate disassembly into smaller, discrete aggregates such as ribbon-like and micellar assemblies in coassembled solutions, enhancing the solubility and dispersion. The TPE moiety exhibits enhanced emission upon tamoxifen interaction, enabling the observation of the coassembled species in an aqueous solution for cell imaging. The tamoxifen-selective fluorescent micelles in the presence of a 1:1 molar ratio of TPE derivative with tamoxifen show enhanced tamoxifen absorption and anticancer effects against MCF-7 breast cancer cells. These supramolecular approaches, based on the coassembly of building blocks with molecular structural similarity, can provide a novel strategy for the efficient development of selective molecular carriers with enhanced biological activities.

Foot deformity and quality of life among independently ambulating children with spina bifida in South Korea.

BACKGROUND: Children with spina bifida (SB) may have congenital or acquired foot deformities due to neurological defects in the spinal cord. As the musculoskeletal system keeps growing, foot deformities can develop or become aggravated. Thus, healthcare providers should provide constant monitoring and proper orthopedic management. Since foot deformities can affect not only the gait but also the daily life of children with SB, it is necessary to investigate the impact of foot deformities on everyday life. The purpose of this study was to examine the relationship between foot deformity and health-related quality of life (HRQoL) among independently ambulating children with SB. METHODS: This cross-sectional study examined the associations between foot deformity and HRQoL using two patient-reported outcome measures (Oxford Ankle Foot Questionnaire, Pediatric Outcomes Data Collection Instrument) in 93 children with SB aged 7-18 years between January 2020 and July 2021. RESULTS: Children with foot deformity (n = 54) reported lower scores in all subscales (physical, school and play, emotional, and footwear) of the Oxford Ankle Foot Questionnaire for children than those without foot deformity (n = 39; p < 0.001). Additionally, in terms of the Pediatric Outcomes Data Collection Instrument, children with foot deformity also reported poorer scores in four subscales (transfer and basic mobility, sports and physical functioning, comfort and pain, happiness with physical functioning; p < 0.001) than those without foot deformity, whereas upper extremity functioning was not significantly affected. Children with foot deformities, particularly those with bilateral foot deformities, equinus deformities, or mixed deformities, which are different types of right and left foot deformities, have a lower perceived HRQoL (p < 0.05). CONCLUSIONS: Among independently ambulating children with SB, those with foot deformities showed lower HRQoL. Moreover, children with foot deformities tend to have other clinical problems, including bladder and bowel dysfunction. Therefore, orthopedic management should consider the multifaceted factors that affect children's daily life and HRQoL.

Flexible Thin-Film Speaker Integrated with an Array of Quantum-Dot Light-Emitting Diodes for the Interactive Audiovisual Display of Multi-functional Sensor Signals.

One of the core technologies for wearable electronics is the use of an interactive display device that is attached to the body or clothes to transmit various bio-signals and environmental stimuli to the user. In this study, we report a flexible audiovisual display device consisting of a polyvinylidene difluoride (PVDF) thin-film speaker stacked on an 8 × 8 array of quantum-dot light-emitting diodes (QD-LEDs) and a multi-functional sensor consisting of temperature and ultraviolet (UV) sensors connected to a pressure sensor, allowing the body temperature and UV exposure to be displayed both visually and acoustically. Polydimethylsiloxane is employed as an insulator between the carbon nanotube (CNT)/polyaniline temperature sensor and the ZnO/CNT UV sensor to form a capacitor-type pressure sensor. With the use of a stretchable polymer substrate, liquid metal Galinstan interconnections, and the flexible Au-grid electrodes, both the PVDF speaker and the QD-LED array are stable under repeated cycles of bending deformation with a bending radius of 7.5 mm. By connecting the audiovisual display device to the skin-attached multi-functional sensor, changes in the body temperature and UV exposure are displayed as LED patterns with accompanying acoustic alarms. This study demonstrates the significant potential of our proposed audiovisual monitoring device and multi-functional sensor for use in health-monitoring applications, especially for the elderly and infants requiring prompt care.

Flexible/Stretchable Supercapacitors with Novel Functionality for Wearable Electronics.

With the miniaturization of personal wearable electronics, considerable effort has been expended to develop high-performance flexible/stretchable energy storage devices for powering integrated active devices. Supercapacitors can fulfill this role owing to their simple structures, high power density, and cyclic stability. Moreover, a high electrochemical performance can be achieved with flexible/stretchable supercapacitors, whose applications can be expanded through the introduction of additional novel functionalities. Here, recent advances in and future prospects for flexible/stretchable supercapacitors with innate functionalities are covered, including biodegradability, self-healing, shape memory, energy harvesting, and electrochromic and temperature tolerance, which can contribute to reducing e-waste, ensuring device integrity and performance, enabling device self-charging following exposure to surrounding stimuli, displaying the charge status, and maintaining the performance under a wide range of temperatures. Finally, the challenges and perspectives of high-performance all-in-one wearable systems with integrated functional supercapacitors for future practical application are discussed.

A Flexible Loudspeaker Using the Movement of Liquid Metal Induced by Electrochemically Controlled Interfacial Tension.

A flexible liquid metal loudspeaker (LML) is demonstrated consisting of a gallium-based eutectic liquid metal (Galinstan) and basic aqueous electrolyte (NaOH(aq) ). The LML is driven by liquid metal motion induced by the electrochemically controlled interfacial tension of the Galinstan in NaOH(aq) electrolyte under an applied alternating current (AC) voltage. The fabricated LML produces sound waves in the human audible frequency band with a sound pressure level of ≈40-50 dB at 1 cm from the device and exhibits mechanical stability under bending deformation with a bending radius of 3 mm. Various sounds can be generated with the LML from a single tone to piano notes and human voices. To understand the underlying mechanism of sound generation by the LML, motion analyses, sound measurements, and electrical characterization are conducted at various frequencies. For the first time, this work suggests a new type of liquid metal-based electrochemically driven sound generator in the field of flexible acoustic devices that can be applied to future wearable electronics.

Dynamically Stretchable Supercapacitor for Powering an Integrated Biosensor in an All-in-One Textile System.

Textile-based electronics have attracted much attention as they can perfectly combine the functionality of wearable devices with the soft and comfortable properties of flexible textile fibers. In this work, we report a dynamically stretchable high-performance supercapacitor for powering an integrated sensor in an all-in-one textile system to detect various biosignals. The supercapacitor fabricated with MWCNT/MoO3 nanocomposite electrodes and nonaqueous gel electrolyte, along the course direction of the fabric, exhibits stable and high electrochemical performance under dynamic and static deformation, including stretching in real time, regardless of the strain rate. The strain sensor created along the wale direction of the fabric shows a high sensitivity of 46.3 under an applied strain up to 60%, a fast response time of 50 ms, and high stability over 10 000 cycles of stretching/releasing. Finally, the supercapacitor and strain sensor are integrated into an all-in-one textile system via liquid-metal interconnections, and the sensor is powered by the stored energy in the supercapacitor. This system sewed into cloth successfully detects strain due to joint movement and the wrist pulse. This work demonstrates the high feasibility of utilizing the fabricated stretchable all-in-one textile system for real-time health monitoring in everyday wearable devices.

Skin-Like, Dynamically Stretchable, Planar Supercapacitors with Buckled Carbon Nanotube/Mn-Mo Mixed Oxide Electrodes and Air-Stable Organic Electrolyte.

For practical applications of high-performance supercapacitors as wearable energy storage devices attached to skin or clothes, the supercapacitors are recommended to have stable mechanical and electrochemical performances during dynamic deformations, including stretching, due to real-time movements of the human body. In this work, we demonstrate a skin-like, dynamically stretchable, planar supercapacitor (SPS). The SPS consists of buckled manganese/molybdenum (Mn/Mo) mixed oxide@multiwalled carbon nanotube (MWCNT) electrodes; organic gel polymer electrolyte of adiponitrile, succinonitrile, lithium bis(trifluoromethanesulfonyl)imide, and poly(methyl methacrylate); and a porous, elastomeric substrate. The addition of an Mn/Mo mixed oxide to the MWCNT film produces an 8-fold increase in the areal capacitance. The use of an organic solvent-based electrolyte enhances the operation cell voltage to 2 V and air stability to one month under ambient air conditions. The fabricated planar supercapacitors are biaxially stretchable up to 50% strain and maintain ∼90% of their initial capacitance after 1000 repetitive stretching/releasing cycles. Furthermore, the SPS exhibits stable electrochemical performance under dynamic stretching in real time regardless of the strain rate and performs reliably during repetitive bending/spreading motions of an index finger while attached to skin.

Stretchable, Skin-Attachable Electronics with Integrated Energy Storage Devices for Biosignal Monitoring.

The demand for novel electronics that can monitor human health, for example, the physical conditions of individuals, during daily life using different techniques from those used in traditional clinic diagnostic facilities is increasing. These novel electronics include stretchable sensor devices that allow various biosignals to be directly measured on human skin without restricting routine activity. The thin, skin-like characteristics of these devices enable stable operation under various deformations, such as stretching, pressing, and rubbing, experienced while attached to skin. The mechanically engineered design of these devices also minimizes the inconvenience caused by long-term wear owing to conformal lamination on the skin. The final form of a skin-attachable device must be an integrated platform with an independent and complete system containing all components on a single, thin, lightweight, stretchable substrate. To fabricate fully integrated devices, various aspects, such as material design for deformable interconnection, fabrication of high-performance active devices, miniaturization, and dense arrangement of component devices, should be considered. In particular, a power supply system is critical and must be combined in an electromechanically stable and efficient manner with all devices, including sensors. Additionally, the biosignals obtained by these sensors should be wirelessly transmitted to external electronic devices for free daily activity. This Account covers recent progress in developing fully integrated, stretchable, skin-attachable devices by presenting our strategies to achieve this goal. First, we introduce several integration methods used in this field to build stretchable systems with a special focus on the utilization of liquid gallium alloy. The unique characteristics and patterning process of liquid metal are summarized. Second, various skin-attachable sensors, including strain, pressure, with enhanced sensitivity and mechanical properties are discussed along with their applications for biosignal monitoring. Dual mode sensors that simultaneously detect temperature and pressure signals without interference are also introduced. Third, we emphasize supercapacitors as promising, efficient energy storage devices for power management systems in wearable devices. Supercapacitors for skin-attachable applications should have a high performance, such as high operation voltage, high energy and power densities, cyclic and air stability and water resistance. For this, strategies to select novel materials for electrode, electrolyte, and encapsulation are suggested. Several approaches to fabricate stretchable supercapacitor systems are also presented. Finally, we introduce recent examples of skin-attachable, stretchable electronics that integrate sensors, power management devices, and wireless data transfer functions on a single elastomer substrate. Conventional wireless technologies, such as near-field communications (NFC) and Bluetooth, are incorporated in miniaturized features on the devices. To date, much research has been performed in this field, but there are still many technologies to develop. The performance of individual devices and mass fabrication techniques should be enhanced. We expect that future electronic devices with fully integrated functions will include advanced human-machine interaction capabilities and expand the overall abilities of the human body.

Highly Durable and Flexible Transparent Electrode for Flexible Optoelectronic Applications.

A highly-durable, highly-flexible transparent electrode (FTE) is developed by applying a composite made of a thin metal grid and a doped conducting polymer onto a colorless polyimide-coated NOA63 substrate. The proposed FTE exhibits a transparency of 90.7% at 550 nm including the substrate and a sheet resistance of 30.3 Ω/sq and can withstand both moderately high-temperature annealing (∼180 °C) and acidic solution (70 °C, pH 0.3) processes without performance degradation. The fabricated FTE yielded good mechanical stability under 10 000 cycles of bending deformations at a bending radius less than 1 mm without degradation of electrical conductivity. The high durability of the proposed FTE allows for the fabrication of flexible energy harvesting devices requiring harsh conditions, such as highly flexible perovskite solar cells (FPSCs) with a steady-state power conversion efficiency (PCE) of 12.7%. Notably, 93% of the original PCE is maintained after 2000 bending cycles at an extremely small bending radius of 1.5 mm. The FPSCs installed on curved surfaces of commercial devices drive them under various environments. The applicability of the proposed FTE is further confirmed via the fabrication of a flexible perovskite light-emitting diode. The proposed FTE demonstrates great potential for applications in the field of flexible optoelectronic devices.

Highly Conductive, Stretchable, and Transparent PEDOT:PSS Electrodes Fabricated with Triblock Copolymer Additives and Acid Treatment.

Here, we report on a highly conductive, stretchable, and transparent electrode of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) fabricated via modification with triblock copolymer, poly(ethylene glycol)- block-poly(propylene glycol)- block-poly(ethylene glycol) (PEO20-PPO70-PEO20, Pluronic P123), and post-treatment with sulfuric acid. The fabricated electrode exhibits high transparency (89%), high electrical conductivity (∼1700 S/cm), and minimal change in resistance (∼4%) under repetitive stretch-release cycles at 40% tensile strain after stabilization. P123 acts as a secondary dopant and plasticizer, resulting in enhanced electrical conductivity and stretchability of PEDOT:PSS. Furthermore, after sulfuric acid post-treatment, P123 helps the electrode to maintain its stretchability. A successful demonstration of the stretchable interconnection was shown by stretching the P123-modified PEDOT:PSS electrodes, which were connected with light-emitting diodes (LEDs) in series. Finally, a stretchable and transparent touch sensor consisting of our fabricated electrodes and an LED array and stretchable semitransparent supercapacitor were presented, suggesting a great potential of our electrodes in the application to various deformable devices.

Wire-Shaped Supercapacitors with Organic Electrolytes Fabricated via Layer-by-Layer Assembly.

A wire-shaped supercapacitor (WSS) has structural advantages of high flexibility and ease of incorporation into conventional textile substrates. In this work, we report a thin reproducible WSS fabricated via layer-by-layer (LbL) assembly of multiwalled carbon nanotubes (MWCNTs), combined with an organic electrolyte of propylene carbonate (PC)-acetonitrile (ACN)-lithium perchlorate (LiClO4)-poly(methyl methacrylate) (PMMA) that extends the voltage window to 1.6 V. The MWCNTs were uniformly deposited on a curved surface of a thin Au wire using an LbL assembly technique, resulting in linearly increased areal capacitance of the fabricated WSS. Vanadium oxide was coated on the LbL-assembled MWCNT electrode to induce pseudocapacitance, hence enhancing the overall capacitance of the fabricated WSS. Both the cyclic stability of the WSS and the viscosity of the electrolyte could be optimized by controlling the mixing ratio of PC to ACN. As a result, the fabricated WSS exhibits an areal capacitance of 5.23 mF cm-2 at 0.2 mA cm-2, an energy density of 1.86 µ W h cm-2, and a power density of 8.5 mW cm-2, in addition to a high cyclic stability with a 94% capacitance retention after 10 000 galvanostatic charge-discharge cycles. This work demonstrates a great potential of the fabricated scalable WSS in the application to high-performance textile electronics as an integrated energy storage device.

Skin-Attachable, Stretchable Electrochemical Sweat Sensor for Glucose and pH Detection.

As part of increased efforts to develop wearable healthcare devices for monitoring and managing physiological and metabolic information, stretchable electrochemical sweat sensors have been investigated. In this study, we report on the fabrication of a stretchable and skin-attachable electrochemical sensor for detecting glucose and pH in sweat. A patterned stretchable electrode was fabricated via layer-by-layer deposition of carbon nanotubes (CNTs) on top of patterned Au nanosheets (AuNS) prepared by filtration onto stretchable substrate. For the detection of glucose and pH, CoWO4/CNT and polyaniline/CNT nanocomposites were coated onto the CNT-AuNS electrodes, respectively. A reference electrode was prepared via chlorination of silver nanowires. Encapsulation of the stretchable sensor with sticky silbione led to a skin-attachable sweat sensor. Our sensor showed high performance with sensitivities of 10.89 µA mM-1 cm-2 and 71.44 mV pH-1 for glucose and pH, respectively, with mechanical stability up to 30% stretching and air stability for 10 days. The sensor also showed good adhesion even to wet skin, allowing the detection of glucose and pH in sweat from running while being attached onto the skin. This work suggests the application of our stretchable and skin-attachable electrochemical sensor to health management as a high-performance healthcare wearable device.

Fabrication of High-Sensitivity Skin-Attachable Temperature Sensors with Bioinspired Microstructured Adhesive.

In this study, we demonstrate the fabrication of a highly sensitive flexible temperature sensor with a bioinspired octopus-mimicking adhesive. A resistor-type temperature sensor consisting of a composite of poly(N-isopropylacrylamide) (pNIPAM)-temperature sensitive hydrogel, poly(3,4-ethylenedioxythiophene) polystyrene sulfonate, and carbon nanotubes exhibits a very high thermal sensitivity of 2.6%·°C-1 between 25 and 40 °C so that the change in skin temperature of 0.5 °C can be accurately detected. At the same time, the polydimethylsiloxane adhesive layer of octopus-mimicking rim structure coated with pNIPAM is fabricated through the formation of a single mold by utilizing undercut phenomenon in photolithography. The fabricated sensor shows stable and reproducible detection of skin temperature under repeated attachment/detachment cycles onto skin without any skin irritation for a long time. This work suggests a high potential application of our skin-attachable temperature sensor to wearable devices for medical and health-care monitoring.

Super-Absorbent Polymer Valves and Colorimetric Chemistries for Time-Sequenced Discrete Sampling and Chloride Analysis of Sweat via Skin-Mounted Soft Microfluidics.

This paper introduces super absorbent polymer valves and colorimetric sensing reagents as enabling components of soft, skin-mounted microfluidic devices designed to capture, store, and chemically analyze sweat released from eccrine glands. The valving technology enables robust means for guiding the flow of sweat from an inlet location into a collection of isolated reservoirs, in a well-defined sequence. Analysis in these reservoirs involves a color responsive indicator of chloride concentration with a formulation tailored to offer stable operation with sensitivity optimized for the relevant physiological range. Evaluations on human subjects with comparisons against ex situ analysis illustrate the practical utility of these advances.

Fully implantable, battery-free wireless optoelectronic devices for spinal optogenetics.

The advent of optogenetic tools has allowed unprecedented insights into the organization of neuronal networks. Although recently developed technologies have enabled implementation of optogenetics for studies of brain function in freely moving, untethered animals, wireless powering and device durability pose challenges in studies of spinal cord circuits where dynamic, multidimensional motions against hard and soft surrounding tissues can lead to device degradation. We demonstrate here a fully implantable optoelectronic device powered by near-field wireless communication technology, with a thin and flexible open architecture that provides excellent mechanical durability, robust sealing against biofluid penetration and fidelity in wireless activation, thereby allowing for long-term optical stimulation of the spinal cord without constraint on the natural behaviors of the animals. The system consists of a double-layer, rectangular-shaped magnetic coil antenna connected to a microscale inorganic light-emitting diode (µ-ILED) on a thin, flexible probe that can be implanted just above the dura of the mouse spinal cord for effective stimulation of light-sensitive proteins expressed in neurons in the dorsal horn. Wireless optogenetic activation of TRPV1-ChR2 afferents with spinal µ-ILEDs causes nocifensive behaviors and robust real-time place aversion with sustained operation in animals over periods of several weeks to months. The relatively low-cost electronics required for control of the systems, together with the biocompatibility and robust operation of these devices will allow broad application of optogenetics in future studies of spinal circuits, as well as various peripheral targets, in awake, freely moving and untethered animals, where existing approaches have limited utility.

A skin-integrated transparent and stretchable strain sensor with interactive color-changing electrochromic displays.

In this study, we report on the development of a stretchable, transparent, and skin-attachable strain sensor integrated with a flexible electrochromic device as a human skin-inspired interactive color-changing system. The strain sensor consists of a spin-coated conductive nanocomposite film of poly(vinyl alcohol)/multi-walled carbon nanotube/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) on a polydimethylsiloxane substrate. The sensor exhibits excellent performance of high sensitivity, high durability, fast response, and high transparency. An electrochromic device (ECD) made of electrochemically synthesized polyaniline nanofibers and V2O5 on an indium-tin-oxide-coated polyethylene terephthalate film experiences a change in color from yellow to dark blue on application of voltage. The strain sensor and ECD are integrated on skin via an Arduino circuit for an interactive color change with the variation of the applied strain, which enables a real-time visual display of body motion. This integrated system demonstrates high potential for use in interactive wearable devices, military applications, and smart robots.

Effective Propagation of Surface Plasmon Polaritons on Graphene-Protected Single-Crystalline Silver Films.

Silver (Ag) is a promising material for manipulation of surface plasmon polaritons (SPPs), due to its optical and electrical properties; however, the intrinsic properties are easily degraded by surface corrosion under atmospheric conditions, restricting its applications in plasmonics. Here, we address this issue via single-crystalline Ag films protected with graphene layers and demonstrate effective propagation of SPPs on the graphene-protected Ag films. Single-crystalline Ag films with atomically flat surfaces are prepared by epitaxial growth; graphene layers are then transferred onto the Ag films. The propagation lengths of SPPs on the graphene-protected Ag films are measured, and their variations under corrosive conditions are investigated. The initial SPP propagation lengths for the bare Ag films are very long (about 50 µm in the wavelength range 550-700 nm). However, the values decrease significantly (11-13 µm) under corrosive conditions. On the contrary, the double-layer-graphene-protected Ag films exhibit SPP propagation lengths of about 23 µm and retain over 90% (21-23 µm) of the propagation lengths even after exposure to corrosive conditions, guaranteeing the reliability of Ag plasmonic devices. This approach can encourage extending the application of the graphene-metal hybrid structure and thus developing Ag plasmonic devices.

Flexible Near-Field Wireless Optoelectronics as Subdermal Implants for Broad Applications in Optogenetics.

In vivo optogenetics provides unique, powerful capabilities in the dissection of neural circuits implicated in neuropsychiatric disorders. Conventional hardware for such studies, however, physically tethers the experimental animal to an external light source, limiting the range of possible experiments. Emerging wireless options offer important capabilities that avoid some of these limitations, but the current size, bulk, weight, and wireless area of coverage is often disadvantageous. Here, we present a simple but powerful setup based on wireless, near-field power transfer and miniaturized, thin, flexible optoelectronic implants, for complete optical control in a variety of behavioral paradigms. The devices combine subdermal magnetic coil antennas connected to microscale, injectable light-emitting diodes (LEDs), with the ability to operate at wavelengths ranging from UV to blue, green-yellow, and red. An external loop antenna allows robust, straightforward application in a multitude of behavioral apparatuses. The result is a readily mass-producible, user-friendly technology with broad potential for optogenetics applications.

Induction of telomere shortening and cellular apoptosis by sodium meta-arsenite in human cancer cell lines.

The present study assessed the cytotoxicity of sodium meta-arsenite (SMA) on telomere shortening and cellular apoptosis in human A-549, MDA-MB-231 and U87-MG cancer cell lines. Following 2 weeks of 1 µM SMA treatment, population doubling time (PDT) was significantly (P < .05) increased by the inhibition of cell proliferation in all the cancer cell lines compared to that in untreated controls. Level of telomerase activity by relative-quantitative telomerase repeat amplification protocol was significantly (P < .05) downregulated by SMA treatment with significant (P < .05) decrease of both telomerase reverse transcriptase and telomerase RNA component transcripts, responsible for telomerase activity. A significant (P < .05) shortening of telomeric repeats by telomere restriction fragment analysis was consequently observed in SMA-treated cells. Moreover, high incidence of cells with senescence-associated ß-glucosidase activity was observed in SMA-treated cells and some cells were also differentiated into adipocytes probably due to the loss of tumorous characterizations. Cellular apoptosis proven by DNA fragmentation was observed, and intrinsic apoptotic transcripts (BAX, caspase 3 and caspase 9) and stress-related transcripts (p21, HSP70 and HSP90) were significantly (P < .05) increased in three cancer cell lines treated with SMA. Based on the present study, SMA treatment apparently induced a shortening of telomere length and cytotoxicity, such as induction of cell senescence, apoptosis and cell differentiation. Therefore, we conclude that SMA treatment at specific concentration can lead to gradual loss of tumorous characterizations and can be considered as a potential anti-cancer drug for chemotherapy treatment.

High performance flexible double-sided micro-supercapacitors with an organic gel electrolyte containing a redox-active additive.

In this study, we report the fabrication of a high performance flexible micro-supercapacitor (MSC) with an organic gel electrolyte containing a redox-active additive, referred to as poly(methyl methacrylate)-propylene carbonate-lithium perchlorate-hydroquinone (PMMA-PC-LiClO4-HQ). Hexagonal MSCs fabricated on thin polyethylene terephthalate (PET) films had interdigitated electrodes made of spray-coated multi-walled carbon nanotubes (MWNTs) on Au. The addition of HQ as a redox-active additive enhanced not only the specific capacitance but also the energy density of the MSCs dramatically, which is approximately 35 times higher than that of MSCs without the HQ additive. In addition, both areal capacitance and areal energy density could be doubled by fabrication of double-sided MSCs, where two MSCs are connected in parallel. The double-sided MSCs exhibited stable electrochemical performance during repeated deformation by bending. By dry-transferring the double-sided MSCs based on PMMA-PC-LiClO4-HQ on a deformable polymer substrate, we fabricated a stretchable MSC array, which also retained its electrochemical performance during a uniaxial strain of 40%. Furthermore, a wearable energy storage bracelet made of such an MSC array could operate a µ-LED on the wrist.