Single body-coupled fiber enables chipless textile electronics.

Intelligent textiles provide an ideal platform for merging technology into daily routines. However, current textile electronic systems often rely on rigid silicon components, which limits seamless integration, energy efficiency, and comfort. Chipless electronic systems still face digital logic challenges owing to the lack of dynamic energy-switching carriers. We propose a chipless body-coupled energy interaction mechanism for ambient electromagnetic energy harvesting and wireless signal transmission through a single fiber. The fiber itself enables wireless visual-digital interactions without the need for extra chips or batteries on textiles. Because all of the electronic assemblies are merged in a miniature fiber, this facilitates scalable fabrication and compatibility with modern weaving techniques, thereby enabling versatile and intelligent clothing. We propose a strategy that may address the problems of silicon-based textile systems.

A Water-Driven and Low-Damping Triboelectric Nanogenerator Based on Agricultural Debris for Smart Agriculture.

The rapid progress in distributed electronics in agriculture depends on a wide range of energy supplies, such as cables and batteries. However, cable installation and maintenance are inconvenient in the agricultural environment, and the massive use of batteries will cause high replacement costs and serious environmental issues. To mitigate these problems, a water flow-driven and high-performance triboelectric nanogenerator based on agricultural debris (including derelict plant fibers and recycled greenhouse film) (AD-TENG) is developed. The precisely designed air gap and plant fiber-based dielectric brushes enable minimized frictional resistance and sustainable triboelectric charges, resulting in low damping and high performance for the AD-TENG. After nano-morphology modifications of the dielectric layer, the maximum power density of the AD-TENG increases by 64 times and reaches ≈1.24 W m-2 . The practical application demonstrates that the AD-TENG realizes the recycling of agricultural debris to achieve harvesting low-frequency and low-speed water-flow energy. Besides, the AD-TENG can be used to power agricultural sensors and develop the automatic irrigation system, which alleviates the energy consumption problem of agriculture and contributes to the realization of automated and informative intelligent agriculture.

Needle-integrated ultrathin bioimpedance microsensor array for early detection of extravasation.

Extravasation is a common complication during intravenous therapy in which infused fluids leak into the surrounding tissues. Timely intervention can prevent severe adverse consequences, but early detection remains an unmet clinical need because existing sensors are not sensitive to leakage occurring in small volumes (< 200 µL) or at deep venipuncture sites. Here, an ultrathin bioimpedance microsensor array that can be integrated on intravenous needles for early and sensitive detection of extravasation is reported. The array comprises eight microelectrodes fabricated on an ultrathin and flexible polyimide substrate as well as functionalized using poly(3,4-ethylenedioxythiophene) and multi-walled carbon nanotubes. Needle integration places the array proximity to venipuncture site, and functional coating significantly reduces interface impedance, both enable the microsensors with high sensitivity to detect early extravasation. In vitro and in vivo experiments demonstrate the capability of the microsensors to differentiate various intravenous solutions from different tissue layers as well as identify saline extravasation with detection limit as low as 20 µL.

Room-temperature high-precision printing of flexible wireless electronics based on MXene inks.

Wireless technologies-supported printed flexible electronics are crucial for the Internet of Things (IoTs), human-machine interaction, wearable and biomedical applications. However, the challenges to existing printing approaches remain, such as low printing precision, difficulty in conformal printing, complex ink formulations and processes. Here we present a room-temperature direct printing strategy for flexible wireless electronics, where distinct high-performance functional modules (e.g., antennas, micro-supercapacitors, and sensors) can be fabricated with high resolution and further integrated on various flat/curved substrates. The additive-free titanium carbide (Ti3C2Tx) MXene aqueous inks are regulated with large single-layer ratio (>90%) and narrow flake size distribution, offering metallic conductivity (~6, 900 S cm-1) in the ultrafine-printed tracks (3 µm line gap and 0.43% spatial uniformity) without annealing. In particular, we build an all-MXene-printed integrated system capable of wireless communication, energy harvesting, and smart sensing. This work opens a door for high-precision additive manufacturing of printed wireless electronics at room temperature.

Growth-Controllable Triboelectric Nanogenerator Based on Surface-Attached Metal-Organic Framework Layer on Living Leaf.

Plant nanoelectronics aims to achieve specific functions by selecting suitable nanomaterials to connect or implant into plants. In this work, a new cyclic-spraying method is developed to attain controllable growth of surface-attached metal-organic framework (SURMOF) coatings on various complex substrates, including cotton, silk, and plant leaves. The covalent bonds formed between the SURMOF layer and substrate enable them to connect firmly without additional adhesive and do not fall off from the microstructured substrate surface with the change of biological activity or environment. Noteworthily, the triboelectric polarity of SURMOF can be regulated by changing the ligand molecule. As a proof of concept, a growth-controllable triboelectric nanogenerator (GC-TENG) based on living leaves and coated SURMOF layer is developed, and the feasibility of using it in the self-driven agricultural monitoring system is explored. In addition, long-term monitoring results show that the growth of SURMOF coating will not cause damage to plant leaf tissue, nor will it affect plant photosynthesis.

Wireless Technologies for Energy Harvesting and Transmission for Ambient Self-Powered Systems.

The era of the Internet of Things (IoT) requires sustainable and convenient methods to power widely distributed sensing devices. Self-powered systems have emerged as a potential solution that utilizes ambient energy from environmental sources such as electromagnetic fields, mechanical motion, solar power, and temperature gradients. Recently, the integration of wireless technologies with self-powered systems has attracted significant attention as a way to address challenges in energy harvesting and transport without the cost and inherent physical constraints of wires. This review summarizes recent progress in the application of wireless technology in self-powered systems for applications in harvesting ambient electromagnetic energy and in transferring power between devices. In addition, challenges and development trends in the future of wireless self-powered sensor networks are discussed.

Highly Efficient Raindrop Energy-Based Triboelectric Nanogenerator for Self-Powered Intelligent Greenhouse.

Establishing a sustainable energy supply is necessary for intelligent greenhouse environmental management. Compared with traditional energy, green and eco-friendly energy is more conducive to protecting the agricultural production environment. In this study, a fluorinated superhydrophobic greenhouse film is proposed as a negative triboelectric layer material for the construction of a triboelectric nanogenerator that harvests raindrop energy (RDE-TENG). Moreover, an upgraded configuration is adopted, where the bulk effect between the lower/upper electrode and film replaces the interfacial effect of the liquid-solid interface, thereby promoting charge transfer. The results show that the RDE-TENG can serve as a sustainable energy source for greenhouse temperature and humidity sensors that assists in realizing intelligent control of the environment and guides agricultural production processes. This device exhibits high-voltage and a stable output; thus, it has the potential to replace traditional energy sources, which helps toward realizing a self-powered intelligent greenhouse planting mode.

Fluorinated Graphene-Enabled Durable Triboelectric Coating for Water Energy Harvesting.

The durability issue of triboelectric nanogenerators (TENGs) still limits its practical application for long-term operation, especially in harvesting water energy, which is one of the most widespread energies in nature. Attempting to ameliorate this, fluorinated graphene (FG) with unique triboelectric negativity and superhydrophobic property is introduced to serve as a new triboelectric and protective layer for TENG construction. The self-cleaning as well as anti-corrosion property and durability of the FG coating-enabled TENG device is then demonstrated. Furthermore, this novel triboelectronegative material candidate is applied for consecutively coating on Cu mesh and the inner wall of sewage pipe to fabricate TENGs for water energy harvesting and working as a metal protective layer in the meantime. Through the extraordinary output performance, the feasibility of FG-enabled triboelectric coating to be used in the field of interference screening, filtering, and sewage pipes is proved. This developed triboelectronegative coating not only broadens the material selection of TENG but also significantly enhances the durability and robustness of TENG for water energy harvesting, which possesses great potential in applying in metal protection and water energy harvesting under extreme conditions (e.g., strong acid and strong alkaline environments).

Self-reduction bimetallic nanoparticles on ultrathin MXene nanosheets as functional platform for pesticide sensing.

Two-dimensional (2D) transition metal carbides and nitrides, named MXene, appear promising application prospects in sensor filed. Metal nanoparticles, especially bimetallic nanoparticles, are the superior nanocatalyst, which process excellent features due to the high specific surface area and synergistic catalytic capacity. Using ultrathin MXene nanosheets as the natural reducing agent and support, we prepare the shape-controlled Au-Pd bimetallic nanoparticles via a self-reduction process at room temperature in a short time, which can well enhance the catalytic performance and are benefit for the acetylcholinesterase immobilization. Based on their desired properties, we propose a disposable electrochemical biosensor for the detection of organophosphorus pesticide using the multi-dimensional nanocomposites (MXene/Au-Pd) as the functional platform. Under the optimized conditions, our fabricated biosensor exhibits a favorable linear relationship with the concentration of paraoxon from 0.1 to 1000 µg L-1, with a low detection limit of 1.75 ng L-1. Furthermore, the biosensor can be applied for paraoxon detection in pear and cucumber samples, providing an effective and useful avenue for the applicability of novel 2D nanomaterials in biosensing field.

Two-dimensional MXene nanosheets (types Ti3C2Tx and Ti2CTx) as new ion-to-electron transducers in solid-contact calcium ion-selective electrodes.

Two kinds of two-dimensional MXene (of type Ti3C2Tx and Ti2CTx) nanosheets are described for use in solid-contact ion-selective electrodes (SC-ISEs) where they act as ion-to-electron transducers. Electrochemical characterizations show that the MXene-coated electrodes possess high double layer capacitance and enable rapid electron transport. This demonstrates the enhanced efficiency of MXene-based solid-contact layers to improve ion-electron transduction. Both Ti3C2Tx- and Ti2CTx-based SC-ISEs exhibited a Nernstian response (26.4 and 24.9 mV/decade, respectively) between 10-1 and 10-5.5 M Ca(II) concentrations with rapid response (<10 s) and low limits of detection (0.79 µM and 1.0 µM, respectively). The SC-ISEs display a lower charge impedance compared to ISEs without solid-contact layer. The new SC-ISEs possess outstanding potentiometric performance, extraordinary long-term stability, and insensitivity to light, CO2, O2, and redox couples, thus showing great promising prospect for routine sensing applications. Graphical abstractSchematic representation of MXene nanosheets for use as new intermediate layers in solid-contact ion-selective electrodes (SC-ISEs) for the potentiometric detection of calcium ion.

Flexible freestanding graphene paper-based potentiometric enzymatic aptasensor for ultrasensitive wireless detection of kanamycin.

Flexible sensing devices have drawn tremendous attention in the past decades due to their potential applications in future hand-held, potable consumer, and wearable electronics. Here, we firstly developed an ultrasensitive wireless potentiometric aptasensor based on flexible freestanding graphene paper for kanamycin detection. Flexible graphene paper made from a simple vacuum filtration method was used as a biocompatible platform for effective immobilization of aptamer. A nuclease-assisted amplification strategy was introduced into this potentiometric biosensing system in order to significantly improve the detection sensitivity through a classic catalytic recycling reaction of target induced by the nuclease (DNase I). As expected, an ultra-low detection limit of 30.0 fg/mL for kanamycin was achieved. Furthermore, the developed potentiometric enzymatic aptasensor exhibits high selectivity, favorable flexibility, excellent stability and reproducibility, which holds great promising for its routine sensing application.

Fully Written Flexible Potentiometric Sensor Using Two-Dimensional Nanomaterial-Based Conductive Ink.

The emerging demand for flexible, portable, easily accessible, and cost-effective electronic fabrication has motivated the development of novel techniques to manufacture electronic components and devices. Inspired by daily hand-writing, an all-written potentiometric sensor was developed by using a Chinese brush pen-based writing technique. A writing ink made from graphene nanosheet (GN) as a conductive component, Triton X-100 as a stabilizer, and xanthan gum as a binder, was used to obtain flexible electrode substrate. Results demonstrate the GN ink-based writing electrode (GN-WE) possesses good conductivity, fast electron-transfer kinetics, considerable stability, and favorable flexibility. By further writing cadmium ion selective membrane (Cd2+-ISM) and photopolymerized reference membrane (RM) on the surface of GN-WE, an all-solid-state potentiometric sensor for cadmium ion was constructed. A large bulk capacitance (41.67 µF) and excellent potential stability (drift of 0.156 mV h-1) were achieved at the developed all-written potentiometric sensor, which is much superior to the solid-contact potentiometric sensor using GCE as electrode substrate. Furthermore, real sample analysis reveals that our GN ink-based potentiometric sensor could be used as a reliable and stable sensor for cadmium ion detection in food and in the environment.

Metallic Transition Metal Dichalcogenide Nanosheets as an Effective and Biocompatible Transducer for Electrochemical Detection of Pesticide.

Owing to their large specific surface, favorable electrical conductivity, and excellent electrocatalytic capabilities, two-dimensional transition metal dichalcogenides have received considerable attention in the field of biosensors. On the basis of these properties, we developed a portable and disposable enzyme-based biosensor for paraoxon detection using a metallic MoS2 nanosheets modified screen-printed electrode (SPE). The exfoliated ultrathin metallic MoS2 nanosheets can accelerate the electron transfer on electrode surface and contribute to the immobilization of acetylcholinesterase (AChE) via the cross-linking of glutaraldehyde. Electrodeposited gold nanoparticles (AuNPs) on SPE were used to immobilize MoS2 nanosheets through the interaction between Au atoms on AuNPs and S atoms on MoS2. Using acetylcholine as the substrate, AChE can catalyze the formation of electroactive thiocholine and further generate the redox current. In the presence of paraoxon, the activity of AChE can be inhibited, making the related electrochemical signals weaken. Under the optimized conditions, this electrochemical biosensor exhibited a favorable linear relationship with the concentration of paraoxon from 1.0 to 1000 µg L-1, with the detection limit of 0.013 µg L-1. Furthermore, this developed biosensor was successfully applied to detect paraoxon in pretreated apple and pakchoi samples, which can provide a reliable method for the rapid analysis of organophosphorus pesticides in agricultural products.

[Protective effect of epigallocatechin-3-gallate on apoptosis of rat cerebellar granule neurons induced by acrylamide].

OBJECTIVE: To investigate the protective effect of epigallocatechin-3 -gallate (EGCG) on apoptosis of cerebellar granule neurons (CGNs) induced by acrylamide (ACR). METHODS: CGNs were cultured with the addition of 5 mmol/L ACR for 24 hours to set up a cell injury model. Prior to ACR treatment, CGNs were treated with different concentrations of EGCG (0, 5, 10, 25, 50, 100 µmol/L) for 48 hours. Neuronal viability was measured with metylthiazdyltetrazolium (MTT). The activity of SOD and the content of MDA were assayed. Hoechst33342 staining was employed to observe morphological changes of the cell nucleus. Reverse transcription-polymerase chain reaction (RT-PCR) was used to measure expression of bcl- 2 mRNA and bax mRNA. RESULTS: At the concentrations of 10, 25 or 50 µmol/L, EGCG played a protective role against ACRinduced CGN injury. Compared with ACR injured group (no EGCG), EGCG improved the cell viability, enhanced SOD activity, decreased the level of MDA as well as the cell apoptosis ratio (P<0.05). Bcl-2 mRNA expression was increased and bax mRNA expression was reduced (P<0.05). 25 µmol/L EGCG had the largest effect. However, 100 µmol/L EGCG did not have a significantly protective effect. CONCLUSION: EGCG at appropriate concentration has protective effect against the CGNs on apoptosis induced by ACR.

[Effect of linear alkylbenzenesulfonate on the reproductive capacity and life-span of Drosophila melanogaster].

OBJECTIVE: To investigate the effect of linear alkylbenzenesulfonate (LAS) on the reproductive capacity and life-span of Drosophila melanogaster. METHODS: Drosophila melanogaster images within 8 h after eclosion were collected with ether anesthesia. The female and male of similar size and normal shape and behavior were selected. The Drosophila melanogasters were cultured in the culture medium containing LAS of different densities. We divided the Drosophila melanogaster into 4 groups according to LAS concentrations: a low dose group with LAS 150 mg/kg, a middle dose group with LAS 300 mg/kg,a high dose group with LAS 600 mg/kg, and a control group without LAS, respectively. The changes of the reproductive capacity, median lethal time, mean life-span and max mean life-span of drosophila melanogaster with different doses of LAS were measured and compared with those of the control. RESULTS: The pupa numbers of filial generation of Drosophila melanogaster in the low, middle, and high dose groups (85.07%, 84.59% and 71.88%, respectively) were lower than those in the control group (P<0.01). The median lethal time, mean life-span and max mean life-span of Drosophila melanogaster in the low, middle, and high dose groups were shorter than those in the control group (P<0.05). The change of life-span of Drosophila melanogaster in the high dose group was remarkable: the median lethal time of female and male shortened 13 days and 15 days, the mean life-span of female and male shortened 18 days and 14 days, and the max mean life-span of female and male shortened 14 days and 12 days, respectively. CONCLUSION: LAS has definite toxicity to Drosophila melanogaster, which can degrade the reproductive capacity of Drosophila melanogaster and shorten the life-span of Drosophila melanogaster.