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Biochemical sensors have become indispensable tools for real-time, on-site monitoring and analysis in diverse domains such as healthcare, environmental protection, and food safety. The rapid evolution of artificial intelligence (AI) has opened new frontiers for enhancing the capabilities of these sensors across a spectrum of detection modalities. This paper delves into the recent integration of AI algorithms into biochemical sensors, examining this advancement from a functional standpoint and focusing on the empowerments it brings to electrochemical, electrochemiluminescence, colorimetric, and Raman sensors. AI techniques aim to enhance the capabilities of biochemical sensors beyond traditional techniques and have enabled improved selectivity, drift correction, efficiency, resolution, assisted diagnosis, and biomarker screening from complex multidimensional data. In the end, we provide a personal perspective on future development and address the remaining challenges in the commercialization of AI-based biochemical sensors. • We introduce the common types and functions of AI algorithms used in biochemical sensors. • AI algorithms enhance biochemical sensors' performance, achieving highly sensitive, precise, and high-throughput analysis. • AI-assisted sensors unlock tremendous benefits across healthcare, environmental protection, and food safety. • A personal perspective on the challenges and future opportunities is discussed. [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]

This review (with 187 refs.) summarizes the progress that has been made in the design of lateral flow biosensors (LFBs) based on the use of micro- and nano-materials. Following a short introduction into the field, a first section covers features related to the design of LFBs, with subsections on strip-based, cotton thread-based and vertical flow- and syringe-based LFBs. The next chapter summarizes methods for sample pretreatment, from simple method to membrane-based methods, pretreatment by magnetic methods to device-integrated sample preparation. Advances in flow control are treated next, with subsections on cross-flow strategies, delayed and controlled release and various other strategies. Detection conditionst and mathematical modelling are briefly introduced in the following chapter. A further chapter covers methods for reliability improvement, for example by adding other validation lines or adopting different detection methods. Signal readouts are summarized next, with subsections on color-based, luminescent, smartphone-based and SERS-based methods. A concluding section summarizes the current status and addresses challenges in future perspectives. [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]

The bioinspired micropatterns exhibit outstanding capacity in controlling and patterning microdroplets, which have offered new functionalities and possibilities towards a wide variety of emerging biological and biomedical applications. By taking the advantages of the microdroplet anchoring ability, enrichment ability, and the accessibility of such bioinspired micropatterns, the selected topic mainly focuses on the important aspects related to (super)wettable surfaces and their emerging sensing applications (DNA, miRNA, proteins, etc.) by combining them with multiple signal output approaches (fluorescence, colorimetric, SERS, electrochemical, etc.). In the end, we also provide a personal perspective on the future development, and address the remaining challenges in the commercialization of (super)wettable micropatterns towards biosensing. [ABSTRACT FROM AUTHOR]

A nanodendritic gold/graphene-based biosensor that can perform fluorescence, SERS and electrochemical tri-modal miRNA detection in a single microdroplet has been developed. The biosensor was used to successfully perform tri-modal quantitative trace miRNA-375 detection, which enormously reduces false positive readings caused by interference and ambiguous signals, and has significant implications for use in precise physiological and pathological diagnosis. [ABSTRACT FROM AUTHOR]

Biochips are a collection of miniaturized test sites (microarrays), which enable researchers to quickly screen large numbers of biological analytes, have become one of the most promising technologies in various biomedical fields. Inspired by self-cleaning property of titanium dioxide (TiO 2 ), a renewable superwettable miRNA biochip (RSMB) was developed for specific and quantitative detection of miRNA-141. The hydrothermal synthesized TiO 2 nanowires on the fluorine-doped tin oxide (FTO) were employed as substrate and provided renewable property. Superhydrophilic microwells were spotted on the superhydrophobic TiO 2 substrate. Due to the extreme wettability difference between the microwell and surrounding substrate, the analytes could be concentrated and anchored onto the microwells from diluted solutions. Such RSMB could be renewable efficiently via photodegrading the organics on the TiO 2 substrate, and consistent results can be obtained after several cycles. This work provided an alternative tool for developing the renewable biochips and shows potential applications in the biomedical diagnosis. [ABSTRACT FROM AUTHOR]

Open-channel droplet arrays have attracted much attention in the fields of biochemical analysis, biofluid monitoring, biomarker recognition and cell interactions, as they have advantages with regard to miniaturization, parallelization, high-throughput, simplicity and accessibility. Such droplet arrays not only improve the sensitivity and accuracy of a biosensor, but also do not require sophisticated equipment or tedious processes, showing great potential in next-generation miniaturized sensing platforms. This review summarizes typical examples of open-channel microdroplet arrays and focuses on diversified biosensing integrated with multiple signal-output approaches (fluorescence, colorimetric, surface-enhanced Raman scattering (SERS), electrochemical, etc.). The limitations and development prospects of open-channel droplet arrays in biosensing are also discussed with regard to the increasing demand for biosensors. [ABSTRACT FROM AUTHOR]

Cotton thread is promising in fabricating biosensors for diagnostic application due to its excellent characteristics. However, the enrichment of the capture molecules on a narrow zone of the cotton thread based biosensor is a big challenge because of its superhydrophilicity. Here, we report a simple, low-cost and accurate cotton thread based nucleic acid biosensor with temperature-dependent pattern. Liquid wax is used to fabricate temperature-dependent pattern to restrict the test zone in a narrow area. This biosensor enables visual and quantitative detection of target DNA by accumulation of gold nanoparticles (GNPs) on the test zone with a detection limits of 0.75 nM. In addition, the cotton thread based biosensor needs less sample than previous reported lateral flow strip and the sample solution wicks faster at the cotton thread which can lead to a shorter detection time. This simple, low-cost and fast detection method holds great potential to improve healthcare services in the developing regions. [ABSTRACT FROM AUTHOR]

The measurement of sulfide, especially hydrogen sulfide, has held the attention of the analytical community due to its unique physiological and pathophysiological roles in biological systems. Electrochemical detection offers a rapid, highly sensitive, affordable, simple, and real-time technique to measure hydrogen sulfide concentration, which has been a well-documented and reliable method. This review details up-to-date research on the electrochemical detection of hydrogen sulfide (ion selective electrodes, polarographic hydrogen sulfide sensors, etc.) in biological samples for potential therapeutic use. [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]

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]

• A target-triggered assembly strategy for Raman imaging of dual cancer biomarkers. • Two detection pathways are independent to produce strong SERS signals. • A potential tool to monitor the expression level of TE and mir-21 in different cell. Imaging multiple classes of intracellular cancer biomarkers provides invaluable insight into the tumor progression and allows cancer diagnosis at the molecular level. The challenge is to develop sensitive, selective and reliable methods for simultaneously imaging different types of cancer biomarkers at low concentrations. Herein, we demonstrated a target-triggered regioselective assembly strategy of plasmonic nanoprobes for dual Raman imaging of microRNA-21 (mir-21) and telomerase (TE) in cells. In the presence of TE, the intense signal of Raman reporter DTNB locating at the "hot spots" of end assembly probes (Au nanoparticles anchored on the terminal of Au nanorods) become weak once the TE triggers the dissociation of end assembly probes and release the DTNB-modified Au nanoparticles from the Au nanorods. Target mir-21 can trigger catalytic hairpin assembly amplification as catalysts and results in the formation of side nanoassemblies that Raman reporter Rox-modified Au nanoparticles anchored onto the side surface of Au nanorods, leading to enhancement in Rox signal. The two independent pathways can efficiently localize target analytes toward "hot spots" to produce strong, amplified SERS signals for the expression level and the dynamic change of mir-21 and TE in different cell lines, providing a potential tool for cancer diagnosis and progression monitor. [ABSTRACT FROM AUTHOR]

Flexible sensors have shown great potential in remote health monitoring, body movements track, electronic skin, human-machine interfaces, and soft robotics. Hydrogels possess exceptional stretchability, flexibility and biocompatibility that render them appealing candidates for wearable flexible sensors. Among them, considerable efforts have been devoted to developing conductive hydrogels to achieve multifunctional wearable sensing through using functional groups/additives/nanofillers to modify the hydrogel network in recent years. This review summarizes recent advances of applications of hydrogels in flexible wearable sensors, such as sweat sampling and flexible electrodes, strain/pressure sensors and touch panels, focuses on the multifunctional conductive hydrogels-based flexible wearable sensors with self-healing, self-adhesion, or anti-freezing capabilities. A brief introduction to representative synthesis methods and strategies of conductive hydrogels is also presented. In the end, we also provide a personal perspective on the future development, and address the remaining challenges in the commercialization of conductive hydrogels-based multifunctional flexible wearable sensors. • We briefly introduce the synthesis methods and strategies of conductive hydrogels. • Flexible hydrogel-based wearable sensors can achieve real-time monitoring physiological signals. • Such sensors exhibit self-healing, self-adhesive or anti-freezing properties. • We provide a personal perspective into the challenges and future commercialization. [ABSTRACT FROM AUTHOR]

Open-channel and high throughput are two important aspects of clinical diagnosis, correlation biochemical analysis, cell culture techniques and food safety. Here, we propose the mini-pillar based array for open-channel and high-throughput SERS detection of miRNA. The polydimethylsiloxane (PDMS) mini-pillars are used as a high-throughput platform, which have good anchoring and aggregation effects on microdroplets, greatly reducing the amount of analytical solution and facilitate the homogeneous sample distribution after evaporation. The deposited gold nanorods (Au NRs) on the pillars with optimized diameter served as SERS-active substrate, can greatly improve the sensitivity of SERS signal compared to other planar substrates. On the open-channel biological chip, sensitive, simultaneous, and specific detection of breast cancer marker miRNA-1246 can be performed. In this mini-pillar array SERS system, the limit of detection (LOD) is 10−12 M. The mini-pillar array shows enormous potential for open channel, high-throughput biomolecular detection, providing an opportunity for biomedical point-of-care testing (POCT) and drug screening. We introduced an open-channel mini-pillar based droplet array as a simple SERS platform for high-throughput detecting the miRNAs. Image 1 • A simple mini-pillar based droplet array platform for high-throughput SERS biosensing was proposed. • Mini-pillar arrays can immobilize microdroplets and reduce the dosage of analytical solution. • High-throughput detection of breast cancer marker can be performed on such platform. [ABSTRACT FROM AUTHOR]

Simultaneous detection of multiple biomarkers is benefit for reducing the detection cycles, avoiding the false-positive signals, and providing the cross validation, which provide the opportunity to understand the pathogenic mechanisms and achieve precise early diagnosis. Here, we demonstrate the mini-pillar-based individual electrochemical array for simultaneous detection of multiple biomarkers. On such platform, the mini-pillar could confine the microdroplet as individual and open-channel microreactor, which is extremely helpful for reducing reagent consumption and extracting internal information, and the electrodes array embedded in mini-pillar are integrated on one side to achieve multiple and simultaneous electrochemical sensing. The introduction of gold nanodendrites by electrodeposition has greatly enhanced sensitivity via improving probe-binding capacity and response signals. Sensitive and selective detection of multiple Alzheimer's biomarkers including Tau, ApoE4, Amyloid-β and miRNA-101 on such mini-pillar-based biosensor is also achieved. Such biosensor platform with the advantages of high-yield, high sensitivity, low-waste and multiple signals output shows great promise in sensing multiple biomolecules for disease diagnosis and health monitoring. • An integrated mini-pillar-based electrochemical sensor is designed. • The optimal gold nanodendrites electrode has the high sensitivity and stability toward electrochemical sensing. • Multiple Alzheimer's biomarkers have been simultaneously detected on such mini-pillar-based electrochemical sensor. [ABSTRACT FROM AUTHOR]

Possessing both unique asymmetric structures and remote-controlled active movement, light-responsive Janus micro-/nanomotors offer the possibility of breaking through the limitations of traditional biomedicine, and have fascinated and inspired researchers. Despite many obstacles toward the clinical application, impressive progress of light-responsive Janus micro-/nanomotors for bioanalytical applications has been made over the past decades. In this review, we first briefly introduced several main light-driven Janus micro-/nanomotors, then focused on their typical bioanalytical applications such as biosensing, bioimaging, and theranostic. In the end, we summarized the remaining challenges of light-responsive Janus micro-/nanomotors in the practical application and also proposed potential solutions in the future. [ABSTRACT FROM AUTHOR]

Ultrasound as a biocompatible and powerful approach has been advanced in biotechnology. Here we present an acoustic microchip integrating modification and detection for in-situ analysis. Such microchip employs two pairs of piezoelectric transducers (PZTs) for acoustic field generation and a polydimethylsiloxane (PDMS) microcavity on a polyethylene terephthalate (PET) substrate for producing microparticle array. The applying of acoustic field results in rapidly forming microparticle array by adjusting the inputting frequency and voltage. In-situ modification and detection are accelerated due to the dynamic ultrasonic streaming around the ultrasound induced microparticle array. Such array also benefits from reducing the detection errors by coupling of multiple points. With this strategy, biomarkers (e.g. miRNA) can be enriched, and achieve in-situ modification and detection via simple two steps with excellent specificity. After the detection, samples are regained from the output channel by releasing the acoustic field, which is benefit for further analysis. Such integrated modification and detection acoustic microchip shows great potential in visual in-situ analysis and enriching ultratrace biomarkers for clinical diagnosis. • An acoustic microchip integrating modification and detection for in-situ analysis was designed. • Such ultrasound-based array also benefits from reducing the detection errors by coupling of multiple points. • The acoustic microchip enables rapidly, real-time and visual biomarkers analysis. [ABSTRACT FROM AUTHOR]

Wearable sweat sensors demonstrate outstanding performance in non-invasive, real-time monitoring of vital biomarkers in sweat, which offer an opportunity for individuals to achieve dynamic monitoring their own physiology in molecular-level. As a key step in sweat analysis that impact the accuracy of results, frequently-used sweat sampling methods are introduced in this review, and the emphasis is sweat sampling in wearable sensors including absorbent materials, superhydrophobic/superhydrophilic surface, sweat guidance and epidermal microfluidic systems. In the end, we also propose the remaining challenges in the practical, large-scale application of wearable sweat sensors and provide personal prospects on the future development. Image 1 • This paper summarized frequently-used sampling methods in emerging wearable sweat sensors. • The basic procedure, advantages and disadvantages of each sampling method have been introduced in details. • Non-invasive wearable sweat devices are promising for better personalized and predictive healthcare after overcoming several remaining challenges. [ABSTRACT FROM AUTHOR]

High throughput and high sensitivity are two important aspects in multiple biomarker recognition, drug discovery and relevant biochemical sensing. Here, we integrate mini-pillar microarray with the circuit components toward high-throughput individual electrochemical sensing in microdroplets. On such droplet-microarray-based electrochemical platform, the high adhesion of the mini-pillar can hold a microdroplet (hundreds nanoliter to a few microliter) regardless of rotation and deformation. Each pillar as a unit has a three-electrode to achieve individual electrochemical sensing, and electrodes are integrated on one side to achieve the sequential electrochemical read-out. Qualitative and quantitative electrochemical assessments of multiple glucose concentrations in individual microdroplets are also achieved. Such mini-pillar-based individual electrochemical platform shows great potential in high-throughput and high-sensitive biomolecular recognitions, provides an opportunity to develop miniaturized sensing platform for emerging biological and pathological applications. • A mini-pillar-array electrochemical sensor is designed. • The mini-pillar-based electrochemical sensor can anchor the microliter droplets for high throughput biosensing. • The mini-pillar-based platform can achieve sensing of multiple glucose concentrations in array microdroplets. [ABSTRACT FROM AUTHOR]

Ultratrace-enriching biomarker analysis is an effective method for achieving highly accurate and enhanced sensitive detection. In this study, we have developed an enrichment detection platform by combining a minipillar array with an aqueous two-phase system (ATPS) for ultratrace enriching biomarker analysis. After optimizing the enrichment conditions of ATPS, target miRNAs at ultratrace levels specifically accumulate in the DEX-rich phase, which significantly increases the target miRNA concentration-related fluorescence intensity. Compared to non-enriched miRNA in the single-phase PEG solution, the detection limit of ATPS-enriched miRNA had improved more than 200-fold. The ATPS-based enrichment detection strategy offers a novel and convenient approach for the simultaneous detection of biomarkers with ultratrace. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) are novel inorganic–organic hybridized crystals with a wide range of applications. In the last twenty years, fluorescence sensing based on MOFs has attracted much attention. MOFs can exhibit luminescence from metal nodes, ligands or introduced guests, which provides an excellent fluorescence response in sensing. However, single-signal emitting MOFs are susceptible to interference from concentration, environment, and excitation intensity, resulting in poor accuracy. To overcome the shortcomings, dual-emission MOF-based ratiometric fluorescence sensors have been proposed and rapidly developed. In this review, we first introduce the luminescence mechanisms, synthetic methods, and detection mechanisms of dual-emission MOFs, highlight the strategies for constructing ratiometric fluorescence sensors based on dual-emission MOFs, and classify them into three categories: intrinsic dual-emission and single-emission MOFs with luminescent guests, and non-emission MOFs with other luminescent materials. Then, we summarize the recent advances in dual-emission MOF-based ratiometric fluorescence sensors in various analytical industries. Finally, we discuss the current challenges and prospects for the future development of these sensors. [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]

Urinalysis is an effective strategy to non-invasively evaluate human health, and surface-enhanced Raman scattering (SERS) may be a powerful technique for use in detecting analytes in urine. Herein, we report a wearable diaper sensor based on a handheld Raman spectrometer for use in the simple, label-free identification of biomolecules (urea, creatinine, and bilirubin) in urine. The raspberry-shaped Au substrate formed on the surface of an Si wafer provides plasmonic enhancement of the SERS signals, with an excellent uniformity and stability. The SERS sensor combines the advantages of flexibility, portability, and multifunctional detection and may be used in identifying multiple analytes in urine. The sensor exhibits high sensitivities in detecting urea, creatinine, and bilirubin, with respective detection limits of 4.17 × 10−3 M, 5.90 × 10−6 M, and 1.38 × 10−7 M (signal-to-noise ratio = 3). Furthermore, we used the wearable diaper sensor to monitor biomolecules at the diagnostic threshold, facilitating non-invasive diagnosis and medical monitoring of disease-related biomarkers. [Display omitted] • Noninvasive plasmonic sensor for multiplex biomarkers determination in urine developed. • The raspberry-shaped Au substrate increases uniformity and stability. • The sensor exhibits high sensitivity in the detection of urea, creatinine, and bilirubin. • A hand-held Raman spectrometer for simple SERS urinalysis. [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]

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 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]

Imprinting "sticky" features on the surfaces of common non-sticky flexible materials, such as paper, textile, and polymeric films produces a myriad of adhesive tapes that we use in our daily lives. Recently, the rise of flexible electronics has harnessed the distinct adhesive behavior of adhesive tapes to achieve special scientific and engineering purposes. In this review, recent advances including the structures, properties, mechanisms, and functionalities of adhesive tapes and relevant flexible smart electronics are summarized. We provide a key focus on how the distinct adhesive behavior of adhesive tapes contributes to the redesign and engineering of flexible electronics via physical and/or chemical modifications. The applications of these flexible smart electronics enabled by adhesive tapes are widespread, including high-performance sensors, energy storage/conversion devices, medical and healthcare patches, etc. Finally, we discuss unmet needs and current challenges in the development of adhesive tape-enabled materials and techniques for flexible electronics. With ongoing material and technical innovations, adhesive tape-related electronic products are expected to revolutionize our lifestyle and lead us into the era of artificial intelligence. [ABSTRACT FROM AUTHOR]

Timely diagnosis and prevention of diseases require rapid and sensitive detection of biomarkers from blood samples without external interference. Abnormal electrolyte ion levels in the blood are closely linked to various physiological disorders, including hypertension. Therefore, accurate, interference-free, and precise measurement of electrolyte ion concentrations in the blood is particularly important. In this work, a colorimetric sensor based on a biphasic microdroplet extraction is proposed for the detection of electrolyte ions in the blood. This sensor employs mini-pillar arrays to facilitate contact between adjacent blood microdroplets and organic microdroplets serving as sensing phases, with any color changes being monitored through a smartphone's colorimetric software. The sensor is highly resistant to interference and does not require pre-treatment of the blood samples. Remarkably, the sensor exhibits exceptional reliability and stability, allowing for rapid enrichment and detection of K+, Na+, and Cl− in the blood within 10 s (Cl−), 15 s (K+) and 40 s (Na+) respectively. The colorimetric sensor based on biphasic microdroplet extraction offers portability due to its compact size and ease of operation without the need for large instruments. Additionally, it is location-independent, making it a promising tool for real-time biomarker detection in body fluids such as blood. A colorimetric detection of multiple electrolyte ions in blood based on biphasic microdroplet extraction. [Display omitted] • Biphasic microdroplet extraction-based colorimetric sensor was developed for detecting three electrolyte ions in blood. • The sensor exhibited outstanding selectivity and stability for rapid detection of K+, Na+, and Cl−. • The sensor is easy to carry and operate, eliminating the need for sample pre-treatment and large instruments. [ABSTRACT FROM AUTHOR]

Levodopa (L -dopa) is an effective medication for Parkinson's disease. However, excess intake from overdose or the intake of natural sources of L -dopa can be dangerous, causing, for example, tardive dyskinesia. Therefore, in medicated individuals, it is important to monitor the levels of L -dopa in the body. In this paper, we report a simple, wearable, noninvasive, and portable metal−organic framework (MOF)-based electrochemical sensor with integrated enzymes for monitoring the concentration of levodopa in sweat, which can be used as a proxy for L -dopa levels in the body. Zeolitic imidazolate framework/graphene oxide (ZIF-8/GO) composites were prepared by the in-situ growth of ZIF-8 nanoparticles on the surface of GO, and, subsequently, tyrosinase was loaded onto the composite to yield the sensor. Integration with a wireless electronic circuit enabled communication between the sensor and a smartphone application for continuous analysis. The sensor was found to have a wide linear response range from 1 to 95 µM, a low limit of detection of 0.45 µM, satisfactory reproducibility, and excellent selectivity. In addition, the sensor showed high sensitivity and good stability as a result of the anchoring of the enzyme. Thus, the sensor shows promise for continuous, noninvasive point-of-care drug monitoring and management. • Noninvasive electrochemical sensor for levodopa determination in sweat developed. • Anchoring tyrosinase on ZIF-8/graphene oxide increases stability and active sites. • Linear electrochemical response over wide concentration range (1–95 µM). • Low limit of detection of 0.45 µM. • Continuous wireless monitoring of volunteers possible during exercise. [ABSTRACT FROM AUTHOR]

Efficient and controlled nanoscalepropulsion in harsh environments requires careful design and manufacturingof nanomachines, which can harvest and translate the propelling forceswith high spatial and time resolution. Here we report a new classof artificial nanomachine, named magneto–acoustic hybrid nanomotor,which displays efficient propulsion in the presence of either magneticor acoustic fields without adding any chemical fuel. These fuel-freehybrid nanomotors, which comprise a magnetic helical structure anda concave nanorod end, are synthesized using a template-assisted electrochemicaldeposition process followed by segment-selective chemical etching.Dynamic switching of the propulsion mode with reversal of the movementdirection and digital speed regulation are demonstrated on a singlenanovehicle. These hybrid nanomotors exhibit a diverse biomimeticcollective behavior, including stable aggregation, swarm motion, andswarm vortex, triggered in response to different field inputs. Suchadaptive hybrid operation and controlled collective behavior holdconsiderable promise for designing smart nanovehicles that autonomouslyreconfigure their operation mode according to their mission or inresponse to changes in their surrounding environment or in their ownperformance, thus holding considerable promise for diverse practicalbiomedical applications of fuel-free nanomachines. [ABSTRACT FROM AUTHOR]

• The hydrogel exhibits antibacterial, hemostatic and adhesive properties. • The hydrogel dressing monitors the wound pH in real-time through colorimetry. • The whole intelligent wound monitoring process mainly include three parts. • A combination of multifunctional hydrogel dressing and machine learning technology. Chronic wound remains a significant challenge in clinical care due to the long treatment process and the poor quality of tissue regeneration affected by bacterial infection, calling timely and effective wound management approach to achieve real-time intelligent wound monitoring and promote wound healing. In this work, a multifunctional hydrogel is employed as wound dressing for intelligent wound monitoring, which not only have the functions of antibacterial, hemostatic and adhesive properties for effectively promoting wound healing, but also can realize real-time wound status monitoring (e.g., pH). The whole intelligent wound monitoring process mainly includes three parts: wound recognition, real-time status monitoring and personalized wound management. Among them, the customized hydrogel wound dressing can accurately match the contour of the wound for precise treatment. Moreover, the personalized wound management model with high accuracy (94.47%) based on the convolutional neural network (CNN) machine learning algorithm can analyze and evaluate the wound healing and infection status through the colorimetric signal of the hydrogel dressing. This multifunctional hydrogel wound dressing, which integrates precise treatment, real-time monitoring and personalized management for intelligent wound monitoring, provides an advanced solution to accelerate wound healing and reduce bacterial infections and plays an inestimable step for future intelligent wound management. [ABSTRACT FROM AUTHOR]

Alzheimer's disease, as a most prevalent type of dementia, is quickly becoming one of the most expensive, lethal, and burdening diseases of this century. Though there are still no efficient therapies, early diagnosis and intervention are important directive significance to clinical works. Here, we develop a portable electrochemical micro-workstation platform consisting of an electrochemical micro-workstation and integrated electrochemical microarray for simultaneously detecting multiple AD biomarkers including Aβ40, Aβ42, T-tau, and P-tau181 in serum. The integrated electrochemical microarray is mainly used for droplet sample manipulation and signal generation. The micro-workstation can regulate signals and transfer the signals to a smartphone by Bluetooth embedded inside. This portable electrochemical micro-workstation platform exhibits excellent analysis performance. The LODs for Aβ40, Aβ42, T-tau, and P-tau181 are 0.125 pg/mL, 0.089 pg/mL, 0.142 pg/mL, and 0.176 pg/mL, respectively, which satisfies the needs of detecting AD biomarkers in serum. The combination of portable micro-workstation and integrated electrochemical microarray provides a promising strategy for the early diagnosis of Alzheimer's disease and personal healthcare. [ABSTRACT FROM AUTHOR]

Continuous physiological monitoring is a promising alternative to current chronic disease management for obtaining big data sets to help individualized therapy. Here, we present a continuous glucose monitoring platform consisting of a screen-printed electrochemical biosensor and a fully integrated wireless electrochemical analysis system. A biocompatible conjugated polymer (poly (N-phenylglycine)) was employed as the support material for enzyme immobilization. Specifically, a polyurethane outer layer was decorated onto the working electrode of the biosensor to construct a diffusion limiting membrane and improve the linear range of the glucose sensor. We optimized the fabricated glucose sensor so that it achieves a linear range of 1–30 mM and a sensitivity of 12.69 μA mM−1·cm−2 in vitro. The long-term stability is up to 30 days by storing in PBS solution at 4°C. The overall system design was very small (0.8 × 1.8 cm) and consisted of a signal conditioning part, a programmable electrochemical chip, and a wireless connection using Bluetooth Low Energy with a smartphone. Finally, we carried out biocompatibility tests and animal experiments to demonstrate the device can successfully monitor blood glucose in vivo. • A flexible, miniaturized and fully integrated wearable CGM system was fabricated. • Chemically synthesized PPG was first employed for GOx immobilization. • Exhibits an excellent linear range of 1–30 mM and long-term stability for 30 days. • The overall system design was very small (0.8 × 1.8 cm). • The biocompatibility tests and animal experiments were carried out. [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]

On-chip microparticle-based separation is a significant activity in analytical and biomedical field. Here, we reported an acoustic aggregation-induced microparticle separation for on-chip fluorescence detection of Alzheimer biomarkers. miRNA-101, an Alzheimer-related biomarker, was used as a model target to validate the performance of the acoustic aggregation-induced separation assay. Under the ultrasound filed, the microparticles would move toward the centre of chip by simply adjusting the frequency and voltage. Such particle aggregation further resulted in fluorescence enhancement comparing with single microparticle. This approach integrated acoustic aggregation-induced microparticle separation with fluorescence enhancement, holding great potential application for the development of lab-on-a-chip based trace biomarkers detection in diagnosis field. [Display omitted] • An acoustic aggregation-induced microparticles separation on a microdevice for the detection of miRNA. • Microparticles aggregation resulted in fluorescence enhancement comparing with single microparticle. • miRNA concentration was converted into FAM fluorescence on microparticle surface by introduction of Exo I. [ABSTRACT FROM AUTHOR]

The novel human infectious coronaviruses (CoVs) responsible for severe respiratory syndromes have raised concerns owing to the global public health emergencies they have caused repeatedly over the past two decades. However, the ongoing coronavirus disease 2019 (COVID-19) pandemic induced by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has received unprecedented attention internationally. Monitoring pathogenic CoVs in environmental compartments has been proposed as a promising strategy in preventing the environmental spread and tracing of infectious diseases, but a lack of reliable and efficient detection techniques is still a significant challenge. Moreover, the lack of information regarding the monitoring methodology may pose a barrier to primary researchers. Here, we provide a systematic introduction focused on the detection of CoVs in various environmental matrices, comprehensively involving methods and techniques of sampling, pretreatment, and analysis. Furthermore, the review addresses the challenges and potential improvements in virus detection techniques for environmental surveillance. [ABSTRACT FROM AUTHOR]

Uric acid (UA) is considered a potential risk factor in the causation or progression of kidney disease. Capabilities in personalized health monitoring enabled by capture and quantitative analysis of uric acid in the interstitial fluid could make up for the limitations of approach assessment of blood samples. Herein, we report a microfluidic−based wearable plasmonic microneedle sensor for interstitial fluid (ISF) sampling and minimally invasive uric acid monitoring. Under the force of the negative pressure generated by finger push. The hollow microneedle array could extract and deliver subcutaneous fluids to the sensing chamber by a microfluidic channel for SERS detection. The SERS sensing chip based on three-dimensional (3D) gold nanoarrays was found to have excellent reproducibility with 5.96% RSD. This high−density microarray showed ultrasensitive and label-free detection of uric acid molecules with a detection limit of 0.51 µM and enable fast identification of target molecules by integration with a handheld Raman spectrometer. The sensing platform may help bring unlimited possibilities for efficient medical healthcare and early disease prevention in daily life. • Plasmonic microneedle sensor for uric acid determination in interstitial fluid developed. • A microfluidic chip enables sampling and delivery ISF from skin by negative pressure. • Linear SERS response over wide concentration range (1 ×10−5 M to 1 ×10−3 M). • Low limit of detection of 0.51 µM. • A handheld Raman spectrometer increase the portability of testing. [ABSTRACT FROM AUTHOR]

Catalytic hairpin assembly (CHA) is a promising enzyme-free, isothermal signal amplification strategy, but the relatively time-consuming strand replacement limits its application scenarios. Here, we developed an ultrasound-enhanced catalytic hairpin assembly (UECHA) biosensing platform for early screening of Alzheimer's disease by introducing a portable acoustic-drive platform with functionalized microspheres for effective biomarkers enrichment and fluorescence enhancement. By constructing a gradient ultrasonic field in a microcavity, the platform concentrates the functionalized microspheres in a central position, accompanied by an enhanced fluorescence signal with a specific release. In addition, the programmable frequency modulation can also modify the acoustic potential well and effectively promote non-equilibrium chemical reactions such as CHA (25 min). Compared with the conventional catalytic hairpin assembly (CHA), UECHA allows for direct and quantitative measurement of AD miRNAs down to 3.55 × 10−15 M in 1 μL samples. This visual analysis of ultra-trace biomarkers based on acoustic enrichment and promotion provides a new perspective for the rapid and highly sensitive clinical detection of Alzheimer's disease. [ABSTRACT FROM AUTHOR]

Artificial intelligence (AI) and wearable sensors are two essential fields to realize the goal of tailoring the best precision medicine treatment for individual patients. Integration of these two fields enables better acquisition of patient data and improved design of wearable sensors for monitoring the wearers' health, fitness and their surroundings. Currently, as the Internet of Things (IoT), big data and big health move from concept to implementation, AI-biosensors with appropriate technical characteristics are facing new opportunities and challenges. In this paper, the most advanced progress made in the key phases for future wearable and implantable technology from biosensing, wearable biosensing to AI-biosensing is summarized. Without a doubt, material innovation, biorecognition element, signal acquisition and transportation, data processing and intelligence decision system are the most important parts, which are the main focus of the discussion. The challenges and opportunities of AI-biosensors moving forward toward future medicine devices are also discussed. • Progress for wearable and implantable technology from biosensing, wearable biosensing to AI-biosensing is summarized. • We emphasized the materials, biorecognition, signal processing, and intelligence decision for AI-biosensor. • The challenges and opportunities of AI-biosensors moving forward toward future medicine devices are also discussed. [ABSTRACT FROM AUTHOR]

Simple, effective, and rapid detection of chemically relevant hazards is a highly desirable research goal, which can provide early-warning information to improve the patient-care outcomes for public health. Here, we introduce a microdroplet-captured tape toward rapid SERS screening of food contaminants. The dominant sensing unit lies on functionalized microwell in conductive carbon tapes, which is simply prepared by physical punching, magnetron sputtering and electrochemical deposition of Au nanodendrites. The tape-based sensors not only possess highly branched Au nanodendrites in microwell for promoting SERS activity, but also enable anchoring the microdroplets via direct dip-pulling from pristine analytes solutions upon sticky incorporated on a glove. Early-warning SERS detection of food contaminants including Sudan-1, thiram, and thiabendazole from the real samples can be achieved by such simple sampling method. These tape-based sensors with a facile operation module and accessible signal read-out represent an innovative point-of-care testing (POCT) device for forensic, military, consumer protection, environmental monitoring, and food safety applications. • The tape-based sensors within Au nanodendrites-modified microwell was designed. • High capillary force among microwell enables rapidly sampling analytes solution. • On-site SERS analysis of real food contaminants in daily life was achieved. [ABSTRACT FROM AUTHOR]

Recent advances in biofluids monitoring have positioned urine as a non-invasive candidate for clinical diagnosis. In this paper, we employ adhesive tapes with indicator-functionalized microarrays for rapid urinalysis. Such tape-based sensor combines advantages of flexibility, adhesive and waterproof functionality in a platform, which is simply prepared by physical punching, fabrics filling and indicators modification. The simulated urine flow can be captured and penetrated in the tape-based microarrays for rapid detection of multiplexed markers such as glucose, nitrite, protein and phenylpyruvate with a smartphone-assisted colorimetric screening method. As a user-friendly point-of-care testing (POCT) approach, such tape-based sensor is ideally favorable for the early disease warning toward the patients of urinary incontinence and infants. [ABSTRACT FROM AUTHOR]

Long-term wearing comfort is essential for future advanced electronic textiles (e-textiles). Herein, we fabricate a skin-comfortable e-textile for long-term wearing experience on human epidermis. Such e-textile was simply fabricated through two different dip coating methods and single-side air plasma treatment, which couples radiative thermal and moisture management for biofluid monitoring. The silk-based substrate with improved optical properties and anisotropic wettability can provide a temperature drop of 1.4 °C under strong sunlight. Moreover, the anisotropic wettability of the e-textile can provide a dryer skin microenvironment by comparing with traditional fabric. The fiber electrodes weaving into the inner side of the substrate can noninvasively monitor multiple sweat biomarkers (i.e., pH, uric acid, and Na+). Such a synergistic strategy may pave a new path to design next-generation e-textiles with significantly improved comfort. [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]

Functionalized textiles with biofluid management capability have attracted tremendous attention in recent years due to their significant roles in health monitoring and dehydration prevention. Here we propose a one-way colorimetric sweat sampling and sensing system based on a Janus fabric using interfacial modification techniques. The opposite wettability of Janus fabric enables sweat to be quickly moved from the skin surface to the hydrophilic side and colorimetric patches. The unidirectional sweat-wicking performance of Janus fabric not only facilitates adequate sweat sampling but also inhibits the backflow of hydrated colorimetric regent from the assay patch toward the skin, eliminating potential epidermal contaminations. On this basis, visual and portable detection of sweat biomarkers including chloride, pH, and urea is also achieved. The results show that the true concentrations of chloride, pH, and urea in sweat are ∼10 mM, ∼7.2, and ∼10 mM, respectively. The detection limits of chloride and urea are 1.06 mM and 3.05 mM. This work bridges the gap between sweat sampling and a friendly epidermal microenvironment, providing a promising way for multifunctional textiles. [Display omitted] • A unidirectional sweat sampling and colorimetric sensing system is fabricated. • Janus fabrics presents the opposite wettability. • The system can achieve sweat sampling and skin-friendly colorimetric detection. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bioinspired jellyfish-like carbon/manganese nanomotor is developed. • Near-infrared light and H 2 O 2 dual-propulsion is achieved. • Cooperation of dual-propulsion and •OH catalytic activity actively enhances tumor chemodynamic therapy. Chemodynamic therapy (CDT), which catalyzes the production of highly toxic reactive oxygen species (ROS), has been widely used in tumor therapy in the past five years. However, most of the current nanomaterials for CDT are difficult to penetrate into the tumor effectively due to the lack of motility, resulting in an unsatisfactory CDT effect. Herein, bioinspired jellyfish-like carbon/manganese nanomotors (JCMNs) are designed to achieve hydrogen peroxide (H 2 O 2) and NIR light dual-propulsion for the enhanced CDT therapy. Based on the jellyfish-like asymmetric structure, the manganese component can catalyze H 2 O 2 to generate chemical concentration gradient, propelling JCMNs to dynamically generate ROS in cells by self-diffusiophoresis. In addition, the carbon component of JCMNs can absorb near-infrared (NIR) light to produce a temperature gradient, driving JCMNs to enhance tumor penetration by self-thermophoresis. The combination of chemical and NIR light propulsions significantly improves the efficiency of tumor CDT, revealing that it should be a reasonable strategy to promote the development of nanobiomedicine by endowing nanosystems with propulsion capacity. [ABSTRACT FROM AUTHOR]

The outbreak of COVID-19 has created a huge challenge to global health systems. Experience in fighting the epidemic shows that the development of a rapid and sensitive POCT diagnostic platform for SARS-CoV-2 that can be deployed in situ is crucial to contain the outbreak. Here, we have developed a portable microdroplet detection platform that integrated temperature controller and micro-stirring for high-throughput and ultrafast COVID-19 diagnosis. Such a device uses a p-n junction (PN junction) as the temperature controller to adjust the temperature in a single microdroplet independently and precisely, ensuring the amplification of reverse transcription loop-mediated isothermal amplification (RT-LAMP). Meanwhile, the platform incorporates an ultrasonic micro-stirring unit, greatly increasing the interaction between RT-LAMP molecules and accelerating the amplification. The results show good linearity over a wide linear range (1 to 105 copies/μL) and low LOD (0.48 copy/μL). Our method reports in only 6.1 min for high-viral load samples, and combines with sample preparation, the total detection process could be done within 30 min. Such a portable and fully integrated microdroplet molecular diagnostic platform is a promising tool for point-of-care diagnosis of COVID-19 and other infectious diseases in resource-limited settings. [Display omitted] • A portable microdroplet array integrated platform for SARS-CoV-2 detection. • The temperature of each microdroplet can be independently and precisely controlled. • Ultrasound-induced microstreaming can enhance the RT-LAMP reaction. • The method presents a low LOD with 0.48 copy/μL and detection time in only 6.1 min. • Such fully integrated device holds promise for rapid and sensitive detection in clinical diagnosis. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel colorimetric-electrochemical dual-mode smartphone sensor was developed. • MOF-818 possesses high peroxidase-like activity under 37 °C and acidic conditions and electrocatalytic activity to H 2 O 2. • H 2 S can coordinate with copper sites of MOF-818 and inhibit the catalytic activity. • The dual-mode sensor exhibited excellent selectivity and sensitivity toward H 2 O 2 and H 2 S. • The dual-mode sensor can be used to monitor H 2 O 2 and H 2 S released from living cells. Hydrogen peroxide (H 2 O 2) and hydrogen sulfide (H 2 S) play a key role in many cellular signaling pathways. The efficient and accurate in situ detection of H 2 O 2 and H 2 S released from living cells has attracted extensive research interests. Herein, we presented a portable colorimetric and electrochemical dual-mode sensor for detection of cellular secreted H 2 O 2 and H 2 S based on MOF-818 nanozyme. MOF-818 containing trinuclear copper centers not only possesses excellent peroxidase-like activity under 37 °C and acidic conditions, but also exhibits outstanding electrocatalytic reduction activity to H 2 O 2 (reduction peak potential at −0.08 V vs Ag/AgCl). Meanwhile, the copper sites of MOF-818 can be coordinated with sulfide, reducing the catalytic activity of MOF-818. As a result, the colorimetric and electrochemical sensing of H 2 O 2 and H 2 S were established based on "signal-on" and "signal-off" strategies, respectively. Additionally, the combination of a smartphone and a miniature electrochemical analyzer enables dual-mode colorimetric and electrochemical sensing platform for in situ detection of H 2 O 2 and H 2 S released from live cells. This portable dual-mode sensor based on MOF nanozyme not only opens a new path for point-of-care testing, but also has potential applications in the field of cell biology and clinical diagnosis. [ABSTRACT FROM AUTHOR]