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The skin, as the body's largest organ, is closely linked to an individual's health. Delayed diagnosis and treatment of skin infections can lead to complications such as non‐healing wounds and sepsis. Despite significant, early identification of wound infections and timely treatment of non‐healing wounds remain a challenge that requires continuous management. This work presents a novel strategy that combines smart microneedle sensing to inhibit wound infection and track wound healing status. The microneedle tip based on metal‐organic frameworks (MOF) hydrogel allows rapid self‐sterilization and promotes wound healing. The substrate of the microneedle patch based on pH–sensitive fluorescent reagents, can integrate with a smartphone to visualize images. Furthermore, it can be further reliably evaluated wound pH by applying a machine‐learning algorithm. The multifunctional microneedle sensing patch establishes a strategy that combines therapy and sensing to address delayed wound management, promotes the design and optimization of MOF hydrogels, and contributes a facile way for disease diagnosis and personalized health management. [ABSTRACT FROM AUTHOR]

The current polymerase chain reactions‐based nucleic acid tests for large‐scale infectious disease diagnosis are always lab‐dependent and generate large amounts of highly infectious plastic waste. Direct non‐linear acoustic driven of microdroplets provide an ideal platform for contactless spatial and temporal manipulation of liquid samples. Here, a strategy to programmable‐manipulate microdroplets using potential pressure well for contactless trace detection is conceptualized and designed. On such contactless modulation platform, up to seventy‐two piezoelectric transducers are precisely self‐focusing single‐axis arranged and controlled, which can generate dynamic pressure nodes for effectively contact‐free manipulating microdroplets without vessel contamination. In addition, the patterned microdroplet array can act as contactless microreactor and allow multiple trace samples (1–5 µL) biochemical analysis, and the ultrasonic vortex can also accelerate non‐equilibrium chemical reactions such as recombinase polymerase amplification (RPA). The results of fluorescence detection indicated that such programmable modulated microdroplet achieved contactless trace nucleic acid detection with a sensitivity of 0.21 copy µL−1 in only 6–14 min, which is 30.3–43.3% shorter than the conventional RPA approach. Such a programmable containerless microdroplet platform can be used for toxic, hazardous, or infectious samples sensing, opening up new avenues for developing future fully automated detection systems. [ABSTRACT FROM AUTHOR]

"Green Synthesis" has been broadly applied in drug synthesis and nanomaterial preparation. The integration of automated micro‐synthesis and high‐throughput screening systems is a key way to achieve the goal of green manufacturing. Here, a one‐click green synthesis platform is designed that integrates droplets arrays‐based micro‐synthesis for Raman enhancement performance high‐throughput screening of MNPs@Cu‐MOF (AuNPs@, AgNPs@, PtNPs@Cu‐MOF) under room temperature and normal pressure. The fully integrated ultrasound units can achieve rapid multi‐component mixing in the droplet array systems, and significantly accelerate materials growth as well as enhance encapsulation of noble metal nanoparticles into Cu‐MOF structures. Based on such integrated systems, structures with high Raman enhancement performance can be high‐throughput evaluation and easily screened out. The results indicated that the AgNPs@Cu‐MOF exhibited the best Raman enhancement performance, which is ≈8 times higher than pure AgNPs. Such a green and integrated platform provides a way for automated multi‐type composites fabrication, which can be expanded to multiple fields in the future via combined robotic platforms and artificial intelligence technology. [ABSTRACT FROM AUTHOR]

Enriching trace targets from trace samples is essential for analytical chemistry. Here, a mini‐pillar platform for biphasic (aqueous and organic) microdroplet–microdroplet extraction for enrichment analysis is demonstrated. Such mini‐pillars with biphasic hydrophobicity can anchor the biphasic microdroplets (organic or aqueous) regardless of rotation and inversion. Methylene blue (MB) and Nile red (NR) are extracted and analyzed by single‐phase extraction, double‐phase extraction, and enrichment analysis. The results display the well linear relationships of all extraction processes with the high extraction efficiency of more than 80% in the single/double phase and up to 500% in the enrichment phase. This work remedies the deficiencies of traditional liquid phase extraction technology, such as extensive sample consumption, low sensitivity, complex equipment, and cumbersome operation. Furthermore, a portable, easy‐manipulation, low‐waste, high‐throughput, and controllable liquid biphasic platform is proposed for high sensitivity, enrichment, and enhanced biphasic extraction analysis. [ABSTRACT FROM AUTHOR]

Here, we demonstrated a mini‐pillar based multi‐channel electrochemical platform that can efficiently adjust multiple electrochemical deposition parameters in the microdroplet arrays to control and predict the final structures of silver nanomaterials. Each mini‐pillar is capable of anchoring microdroplet to form a separate microreactor, and the electrodes are integrated to achieve a multi‐channel electrochemical electrodeposition platform. We systematically investigated the multiple deposition parameters of silver nanostructures and summarized the relevant experience of electrochemical silver deposition to guide silver nanostructure preparation. Such the mini‐pillar based microdroplet platform provides an approach for further high‐throughput and intelligent nanomaterial fabrication. [ABSTRACT FROM AUTHOR]

Many studies have focused on effective ways to exploit enzyme immobilization on an electrode surface to help improve the performance of enzymatic electrochemical biosensors. Herein, a novel glucose sensor was fabricated by immobilizing glucose oxidase (GOx) onruthenium‐based conjugated polymer (CP) and metal‐organic framework (MOF) nanocomposites. This has not only reduced the applied potential to 0.2 V (vs. Ag/AgCl), but also improved the effective surface area for enzyme immobilization.PPG@Ru@UiO‐66‐NH2 was tailored by controlled chemical synthesis from a pre‐synthesized water‐soluble conjugated polymer (poly(N‐phenylglycine)) and metal‐organic framework (UiO‐66‐NH2). The resulting nanocomposites were characterized using Fourier transform infrared spectroscopy, X‐ray fluorescence, scanning electron microscopy, and cyclic voltammetry. The PPG@Ru@UiO‐66‐NH2/GOx coated electrodedisplayed a linear measurementrange for glucose from 1 mM to 10 mM, with a sensitivity of 45.92 μA ⋅ mM−1cm−1 and limit of detection of5 μM(S/N=3). Furthermore, the practical application of the fabricatedglucosesensor was tested in simulative blood samples with satisfactoryaccuracy. This approach alsoopens a new door for applications regarding both enzymatic electrochemical biosensors and enzymatic biofuel cells (EBFCs). [ABSTRACT FROM AUTHOR]

Directional transportation as is a common phenomenon in nature, has significant potential in advanced devices and technology. Most of the studies focus on the directional transport of water on an anisotropic surface with gradients in Laplace pressure. However, rare attentions are paid to on‐demand transportation of macroscale object on static microscale anisotropic structure. Herein, bioinspired by the phenomenon that the breath air promotes the mucus gel transport in trachea, a transport system by combining static microcilia with anisotropic structure, water layer, and air‐blowing device, realizing directional transport of macroscale object under air flow is fabricated. Owing to the anisotropic friction, the anisotropic microcilia arrays achieve transporting centi‐scale hydrogel slice when air flow along their tilted direction. In contrast, air flow against their tilted direction results in hard transport. By introducing cobalt nanoparticles into microcilia, the transport direction can also be easy tuned by regulating the magnetic field. This contribution should expand more properties and functions of anisotropic surface, and provides a clue to design the next generation of micro‐electromechanical systems. [ABSTRACT FROM AUTHOR]

We report core@satellite Janus mesoporous silica‐Pt@Au (JMPA) nanomotors with pH‐responsive multi‐phoretic propulsion. The JMPA nanomotors first undergo self‐diffusiophoretic propulsion in 3.0 % H2O2 due to the isolation of the Au nanoparticles (AuNPs) from the PtNPs layer. Then the weak acidity of H2O2 can trigger the disassembly and reassembly of the AuNPs, resulting in the Janus distribution of large AuNPs aggregates. Such reconstruction of JMPA leads to the contact between PtNPs and AuNPs aggregates, thus changing the propulsion mechanism to self‐electrophoresis. The asymmetric and aggregated AuNPs also enable the generation of a thermal gradient under laser irradiation, which propels the JMPA nanomotors by self‐thermophoresis. Such multi‐phoretic propulsion offers considerable promise for developing advanced nanomachines with a stimuli‐responsive switch of propulsion modes in biomedical applications. [ABSTRACT FROM AUTHOR]

The efficiency and accuracy of material fabrication are closely related to the quantity and quality of material structures/properties, which usually involves multiple parameters with high cost and time waste. Here, an intelligent and high‐throughput platform is developed to regulate multiple electrodeposition parameters of a microdroplets array for controlling and predicting nanostructures. On such platform, the minipillars can anchor the microdroplets as individual deposition reactors, and the electrodes are integrated on one side to achieve high‐throughput and simultaneous electrochemical fabrication. Such integrated and intelligent platform has been employed to investigate gold nanostructures via regulating the deposition parameters (time, potential, HAuCl4 concentration, Cl−/SO42− concentration in electrolyte, temperature, and humidity), and to establish the database of electrochemically‐fabricated gold nanostructures for guiding the design and fabrication of specific gold nanostructures. It is believed that such platform can act as a pioneer to promote the development of materials science by coupling intelligence technology with nanomaterial fabrication. [ABSTRACT FROM AUTHOR]

The assembly of micro‐nanoparticles is one of the key tasks for controlling and manipulating the structure of materials at micro/‐nanoscale. By carefully designing the ultrasound experiments and comparing the results with acoustic theories, we presented an in‐depth study of the ultrasound‐induced assembly behaviors of micro/‐nanoparticles (microparticle size≪wavelength), especially their dynamic interactions between microparticles. The whole assembly processes including floating micro/nanoparticles, single particle communication, assembly to single particle interactions, and reorganization of assembly are fully studied. A rapid response of the ultrasound‐based assembly (0.5 min) shows distinct advantages compared to those of previously used methods such as light‐, electrical‐ and temperature‐based ones. Such an efficient and effective microparticle assembly holds great promise for fabrication of complex structure of materials. [ABSTRACT FROM AUTHOR]

Interaction behaviors are a crucial, distinctive feature of organisms in ecological systems. Inspired by nature, micro‐/nanorobots also show interaction behaviors with a significant number of novel and advanced functionalities. The micro‐/nanoscale size and self‐driven abilities of micro‐/nanorobots have attracted considerable attention for potential applications. The mission of micro‐/nanorobots has evolved from basic mechanical transfer or assistance to a diverse range of complex tasks, such as targeted drug delivery, biosensing, and environmental remediation. Herein, we focus on the interaction behavior of coexisting cooperative cognitive (Tri‐Co) micro‐/nanorobots, summarize recent research, and classify the interactions into three broad types: with the environment, with robot peers, and with human external control. [ABSTRACT FROM AUTHOR]

A red blood cell membrane-camouflaged nanowire that can serve as new generation of biomimetic motor sponge is described. The biomimetic motor sponge is constructed by the fusion of biocompatible gold nanowire motors and RBC nanovesicles. The motor sponge possesses a high coverage of RBC vesicles, which remain totally functional due to its exclusively oriented extracellular functional portion on the surfaces of motor sponge. These biomimetic motors display efficient acoustical propulsion, including controlled movement in undiluted whole blood. The RBC vesicles on the motor sponge remain highly stable during the propulsion process, conferring thus the ability to absorb membrane-damaging toxins and allowing the motor sponge to be used as efficient toxin decoys. The efficient propulsion of the motor sponges under an ultrasound field results in accelerated neutralization of the membrane-damaging toxins. Such motor sponges connect artificial nanomotors with biological entities and hold great promise for treating a variety of injuries and diseases caused by membrane-damaging toxins. [ABSTRACT FROM AUTHOR]

Nitric oxide (NO) plays an important role in physiological processes and it has been confirmed some human diseases are related to its biological function. Electrochemical sensors provide an efficient way to explore the NO function in biological processes. This review details different kinds of electrochemical sensors used for NO concentration detection between 2008 and 2013 together with their application in biological samples. Four commonly used electrodes and different assisted analysis membranes used for contributions towards the development of the novel sensors were summarized. Electrochemical sensors employed to measure NO concentration in a single cell, cell culture, tissue homogenate, organ, in vivo, human being, as well as in plant were also detailed. The trends of developing novel NO sensors were outlooked in the last part. [ABSTRACT FROM AUTHOR]

The last decades have witnessed rapid growth of hydrogel bioelectronics. Traditional hydrogels face challenges when working under extreme conditions, leading to a loss of stabilities and functionalities. This review provides a systematic overview of hydrogels capable of working under extreme conditions, with a focus on their applications in bioelectronic systems. These hydrogels are summarized into categories of anti‐mechanical damage, anti‐detachment, anti‐swelling, anti‐freezing, and anti‐foreign body response. Strategies including material development and structural design that can endow the hydrogels with the above extreme properties are introduced. Finally, current challenges and new opportunities in developing extreme hydrogel bioelectronic devices and systems are discussed. [ABSTRACT FROM AUTHOR]

Motion modulation of functional micro‐/nanoparticles is a key challenge for biomedical science and development of optics and electronics. Herein, microrail‐assisted reversible assemblies of nanowires remotely powered by acoustic waves are demonstrated. The microrails embedded into the ultrasound field can make the surrounding acoustic potential nonuniform distribution and cause nanowires to trap into and assemble along the microrails. The width of the microrail can determine the dynamic assembly of nanowires in parallel to or in perpendicular to the direction of the microrail, which is validated by numerical simulations. In addition, trapping and transportation of nanowires on microrails are also achieved by adjusting the microfluidic direction from the microrail. Such microrail‐assisted capabilities of assembling and transporting nanowires provide great potentials in photonic crystals, cell collection, and nanoelectronic fabrication. [ABSTRACT FROM AUTHOR]