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Transconductance (gm) is one important figure of merit for benchmarking organic electrochemical transistor (OECT) biosensors, which nevertheless experiences undesired fluctuation instead of keep constant during the target detection of varied concentrations. Light‐matter interplay is recently shown as a potential way to regulate the OECT characteristics, e.g. maximum gm at zero gate bias is achieved. In this work, the challenge of unstable gm is addressed by using a unique metal‐organic framework (MOF)‐derived hollow tube indium sulfide (m‐In2S3) as the photogate. Interestingly, the light irradiation on m‐In2S3 generate a straight transfer curve, leading to a stable gm that is desirable for biological application. Exemplifying by an aptasening, such a device is then tested for protein quantification with a stable sensitivity during the detection. This work features the feasibility of light‐matter interplay to achieve a stable gm in organic electronics. [ABSTRACT FROM AUTHOR]

This study explores the mechanism of enhanced electrochemiluminescence (ECL) due to the coupling effect in gold nanodimers (Au NDs) with precisely controlled interparticle distances via electrochemiluminescence microscopy (ECLM). Our research revealed that the enhancement in ECL was predominantly attributed to increased charge density and elevated electric fields resulting from overlapping electrochemical double layers. These findings offer new insights into the fundamental processes that govern nanostructure-mediated electrocatalysis, opening up exciting possibilities for future applications. [ABSTRACT FROM AUTHOR]

Designing dynamic assemblies in living cells is crucial for creating organelle‐like structures, yet precisely controlling their morphological transitions in response to specific signals is a significant challenge. In this study, a DNA framework is combined with hybridization chain reaction (HCR) to achieve specific assembly of hyperbranched aggregates in cancer cells. HCR, distinguished for its signal amplification and linear extension capabilities, enables the morphological transition of precursors to be specifically triggered by trace amounts of endogenous microRNA‐21 (miR‐21). The spatial constraints of the framework and the diversity of hairpin orientations significantly accelerate the assembly kinetics of hyperbranched networks, and the resulting micrometer‐scale aggregates possess enhanced intracellular retention capabilities. Introducing Ce6 molecules as a proof of concept, the regulatory function of aggregates can be activated under light irradiation and remains effective over a long period. The probe we constructed demonstrates good stability and biocompatibility, offers easy functionalization, and works inside cells long‐term, making it an ideal candidate material for the construction of organelle‐like structures. [ABSTRACT FROM AUTHOR]

This study explores plasmon-induced electrochemical reactions on single nanoparticles using electrogenerated chemiluminescence microscopy (ECLM). Under laser irradiation, real-time screening showed lower plasmon-induced reaction efficiency for bimetallic Au@Pt nanoparticles compared to monometallic Au nanoparticles. ECLM offers a high-throughput imaging and precise quantitative approach for analyzing photo-electrochemical conversion at single nanoparticle level, valuable for both theoretical exploration and optimization of plasmonic nanocatalysts. [ABSTRACT FROM AUTHOR]

This work reports the construction of a miniaturized Ag/AgCl nanoelectrode on a nanopipette, which is capable of dual-functions of single-cell drug infusion and chloride detection and is envisioned to promote the study of chloride-correlated therapeutic effects. [ABSTRACT FROM AUTHOR]

Full utilization of the excited species at both singlet states (1R*) and triplet states (3R*) is crucial to improving electrochemiluminescence (ECL) efficiency but is challenging for organic luminescent materials. Here, an aggregation‐induced delayed ECL (AIDECL) active organic dot (OD) containing a benzophenone acceptor and dimethylacridine donor is reported, which shows high ECL efficiency via reverse intersystem crossing (RISC) of non‐emissive 3R* to emissive 1R*, overcoming the spin‐forbidden radiative decay from 3R*. By introducing dual donor‐acceptor pairs into luminophores, it is found that nonradiative pathway could be further suppressed via enhanced intermolecular weak interactions, and multiple spin‐up conversion channels could be activated. As a consequence, the obtained OD enjoys a 6.8‐fold higher ECL efficiency relative to the control AIDECL‐active OD. Single‐crystal studies and theoretical calculations reveal that the enhanced AIDECL behaviors come from the acceleration of both radiative transition and RISC. This work represents a major step towards purely organic, high‐efficiency ECL dyes and a direction for the design of next‐generation ECL dyes at the molecular level. [ABSTRACT FROM AUTHOR]

For the first time, we report novel aggregation-induced electrochemiluminescence (AIECL) of organic dots in aqueous media, with near-infrared II (NIR-II) luminescence peaked at 906 nm. Furthermore, a hybrid mechanism of ECL generation is revealed by various experiments in conjunction with theoretical calculations. This work opens a window for exploring efficient organic dye-based NIR-II AIECL emitters. [ABSTRACT FROM AUTHOR]

The transport behavior of ions in the nanopores has an important impact on the performance of the electrochemical devices. Although the classical Transmission‐Line (TL) model has long been used to describe ion transport in pores, the boundary conditions for the applicability of the TL model remain controversial. Here, we investigated the transport kinetics of different ions, within nanochannels of different lengths, by using transient single‐particle imaging with temporal resolution up to microseconds. We found that the ion transport kinetics within short nanochannels may deviate significantly from the TL model. The reason is that the ion transport under nanoconfinement is composed of multi basic stages, and the kinetics differ much under different stage domination. With the shortening of nanochannels, the electrical double layer (EDL) formation would become the "rate‐determining step" and dominate the apparent ion kinetics. Our results imply that using the TL model directly and treating the in‐pore mobility as an unchanged parameter to estimate the ion transport kinetics in short nanopores/nanochannels may lead to orders of magnitude bias. These findings may advance the understanding of the nanoconfined ion transport and promote the related applications. [ABSTRACT FROM AUTHOR]

The transport behavior of ions in the nanopores has an important impact on the performance of the electrochemical devices. Although the classical Transmission‐Line (TL) model has long been used to describe ion transport in pores, the boundary conditions for the applicability of the TL model remain controversial. Here, we investigated the transport kinetics of different ions, within nanochannels of different lengths, by using transient single‐particle imaging with temporal resolution up to microseconds. We found that the ion transport kinetics within short nanochannels may deviate significantly from the TL model. The reason is that the ion transport under nanoconfinement is composed of multi basic stages, and the kinetics differ much under different stage domination. With the shortening of nanochannels, the electrical double layer (EDL) formation would become the "rate‐determining step" and dominate the apparent ion kinetics. Our results imply that using the TL model directly and treating the in‐pore mobility as an unchanged parameter to estimate the ion transport kinetics in short nanopores/nanochannels may lead to orders of magnitude bias. These findings may advance the understanding of the nanoconfined ion transport and promote the related applications. [ABSTRACT FROM AUTHOR]

Three new hasubanan-type alkaloids, stephalonine Q (1), stephalonine R (2) and stephalonine S (3), together with four known alkaloids, isolonganone (4), eletefine (5), aurantiamide (6), N-cinnamoyltyramine (7), were isolated from the whole plant of Stephania longa. Their structures were identified by NMR, HR-ESI-MS, CD methods and x-ray crystallography, as well as by comparison with the literature data. All isolated compounds were evaluated for their antimicrobial activities against five bacteria in vitro. Compound 5 displayed inhibitory activity against only S. aureus, with an MIC value of 50 μg/mL. [ABSTRACT FROM AUTHOR]

Construction of white‐light emitters is of great importance in practical applications but is challenging for metal nanoclusters. Herein, arginine (Arg)‐mediated copper nanoclusters (Cu NCs) assemblies with white‐light emission (WLE) are reported for the first time. The multidentate ligand, Arg, not only effectively tailors the high stability and locally‐excited emission (LES) of aqueous phase Cu NCs, but also bridges 1‐naphthalenol methylcarbamate (NMC) to generate a blue emitter via through‐space interactions (TSIs), resulting in a stable mixed light. Density functional theory calculation and mass spectrum further confirm that Arg can allow for the formation of strong hydrogen‐bonds with the ligand 2,4‐diaminotoluene of Cu NCs, and formation of TSIs‐based complexes with NMC. More importantly, pure white‐light emission (WLE) with Commission Internationale de L'Eclairagecoordination (0.30, 0.31) is observed by regulating the ratio between Arg and the interfacial ligand of NMC. The findings not only provide a new perspective for the construction of WLE emitters via interface modification chemistry but also open a window to gain insight into the mechanism of interface engineering. [ABSTRACT FROM AUTHOR]

Single‐cell epigenetics is envisioned to decipher manifold epigenetic phenomena and to contribute to our accurate knowledge about basic epigenetic mechanisms. Engineered nanopipette technology has gained momentum in single‐cell studies; however, solutions to epigenetic questions remain unachieved. This study addresses the challenge by exploring N6‐methyladenine (m6A)‐bearing deoxyribozyme (DNAzyme) confined within a nanopipette for profiling a representative m6A‐modifying enzyme, fat mass and obesity‐associated protein (FTO). Electroosmotic intracellular extraction of FTO could remove the m6A and cause DNAzyme cleavage, leading to the altered ionic current signal. Because the cleavage can release a DNA sequence, we simultaneously program it as an antisense strand against FTO‐mRNA, intracellular injection of which has been shown to induce early stage apoptosis. This nanotool thus features the dual functions of studying single‐cell epigenetics and programmable gene regulation. [ABSTRACT FROM AUTHOR]

Single‐cell epigenetics is envisioned to decipher manifold epigenetic phenomena and to contribute to our accurate knowledge about basic epigenetic mechanisms. Engineered nanopipette technology has gained momentum in single‐cell studies; however, solutions to epigenetic questions remain unachieved. This study addresses the challenge by exploring N6‐methyladenine (m6A)‐bearing deoxyribozyme (DNAzyme) confined within a nanopipette for profiling a representative m6A‐modifying enzyme, fat mass and obesity‐associated protein (FTO). Electroosmotic intracellular extraction of FTO could remove the m6A and cause DNAzyme cleavage, leading to the altered ionic current signal. Because the cleavage can release a DNA sequence, we simultaneously program it as an antisense strand against FTO‐mRNA, intracellular injection of which has been shown to induce early stage apoptosis. This nanotool thus features the dual functions of studying single‐cell epigenetics and programmable gene regulation. [ABSTRACT FROM AUTHOR]

Classic tris(bipyridine)ruthenium(II) complex (Ru-bpy) with high electrochemiluminescence (ECL) efficiency still suffers from a serious aggregation-caused quenching (ACQ) problem, which greatly weakens its ECL efficiency to restrict further applications in solid-state ECL imaging and light-emitting devices. Herein, the crystallization-induced enhanced ECL (CIE-ECL) of tris(bipyridine) ruthenium(II) derivatives (Ru-TPE) are reported by decorating Ru-bpy with inherent aggregation-induced emission active tetraphenylethene (TPE), which effectively eliminates the detrimental π-π stacking interactions and thus helps Ru-bpy surmount notorious ACQ effect in the aqueous phase. The Ru-TPE shows negligible ECL emission in solution but produces a strong ECL emission upon crystallization. Surprisingly, the ECL efficiency of Ru-TPE crystals is 20 and 3 times higher than that of its solution and Ru-bpy crystals, respectively. Experimental and structural analysis reveals that such a CIE-ECL effect originates from the restricted intramolecular rotation and ordered molecular packing. Moreover, the high-resolution ECL imaging of a single Ru-TPE crystal is successfully demonstrated. This work provides a new design strategy for achieving high efficiency in solid-state ECL imaging and devices. [ABSTRACT FROM AUTHOR]

Cuproptosis is a new form of programmed cell death and exhibits enormous potential in cancer treatment. However, reducing the undesirable Cu ion release in normal tissue and maximizing the copper‐induced therapeutic effect in cancer sites are two main challenges. In this study, we constructed a photothermally triggered nanoplatform (Au@MSN‐Cu/PEG/DSF) to realize on‐demand delivery for synergistic therapy. The released disulfiram (DSF) chelated with Cu2+ in situ to generate highly cytotoxic bis(diethyldithiocarbamate)copper (CuET), causing cell apoptosis, and the formed Cu+ species promoted toxic mitochondrial protein aggregation, leading to cell cuproptosis. Synergistic with photothermal therapy, Au@MSN‐Cu/PEG/DSF could effectively kill tumor cells and inhibit tumor growth (inhibition rate up to 80.1 %). These results provide a promising perspective for potential cancer treatment based on cuproptosis, and may also inspire the design of advanced nano‐therapeutic platforms. [ABSTRACT FROM AUTHOR]

Cuproptosis is a new form of programmed cell death and exhibits enormous potential in cancer treatment. However, reducing the undesirable Cu ion release in normal tissue and maximizing the copper‐induced therapeutic effect in cancer sites are two main challenges. In this study, we constructed a photothermally triggered nanoplatform (Au@MSN‐Cu/PEG/DSF) to realize on‐demand delivery for synergistic therapy. The released disulfiram (DSF) chelated with Cu2+ in situ to generate highly cytotoxic bis(diethyldithiocarbamate)copper (CuET), causing cell apoptosis, and the formed Cu+ species promoted toxic mitochondrial protein aggregation, leading to cell cuproptosis. Synergistic with photothermal therapy, Au@MSN‐Cu/PEG/DSF could effectively kill tumor cells and inhibit tumor growth (inhibition rate up to 80.1 %). These results provide a promising perspective for potential cancer treatment based on cuproptosis, and may also inspire the design of advanced nano‐therapeutic platforms. [ABSTRACT FROM AUTHOR]

Tumor‐targeted and stimuli‐activatable nanosensitizers are highly desirable for cancer theranostics. However, designing smart nanosensitizers with multiple imaging signals and synergistic therapeutic activities switched on is challenging. Herein, we report tumor‐targeted and redox‐activatable nanosensitizers (1‐NPs) for sono‐photodynamic immunotherapy of tumors by molecular co‐assembly and redox‐controlled disassembly. 1‐NPs show a high longitudinal relaxivity (r1=18.7±0.3 mM−1 s−1), but "off" dual fluorescence (FL) emission (at 547 and 672 nm), "off" sono‐photodynamic therapy and indoleamine 2,3‐dioxygenase 1 (IDO1) inhibition activities. Upon reduction by glutathione (GSH), 1‐NPs rapidly disassemble and remotely release small molecules 2‐Gd, Zn‐PPA‐SH and NLG919, concurrently switching on (1) dual FL emission, (2) sono‐photodynamic therapy and (3) IDO1 inhibition activities. After systemic injection, 1‐NPs are effective for bimodal FL and magnetic resonance (MR) imaging‐guided sono‐photodynamic immunotherapy of orthotropic breast and brain tumors in mice under combined ultrasound (US) and 671‐nm laser irradiation. [ABSTRACT FROM AUTHOR]

Tumor‐targeted and stimuli‐activatable nanosensitizers are highly desirable for cancer theranostics. However, designing smart nanosensitizers with multiple imaging signals and synergistic therapeutic activities switched on is challenging. Herein, we report tumor‐targeted and redox‐activatable nanosensitizers (1‐NPs) for sono‐photodynamic immunotherapy of tumors by molecular co‐assembly and redox‐controlled disassembly. 1‐NPs show a high longitudinal relaxivity (r1=18.7±0.3 mM−1 s−1), but "off" dual fluorescence (FL) emission (at 547 and 672 nm), "off" sono‐photodynamic therapy and indoleamine 2,3‐dioxygenase 1 (IDO1) inhibition activities. Upon reduction by glutathione (GSH), 1‐NPs rapidly disassemble and remotely release small molecules 2‐Gd, Zn‐PPA‐SH and NLG919, concurrently switching on (1) dual FL emission, (2) sono‐photodynamic therapy and (3) IDO1 inhibition activities. After systemic injection, 1‐NPs are effective for bimodal FL and magnetic resonance (MR) imaging‐guided sono‐photodynamic immunotherapy of orthotropic breast and brain tumors in mice under combined ultrasound (US) and 671‐nm laser irradiation. [ABSTRACT FROM AUTHOR]

Single‐cell protein therapeutics is expected to promote our in‐depth understanding of how a specific protein with a therapeutic dosage treats the cell without population averaging. However, it has not yet been tackled by current single‐cell nanotools. We address this challenge by the use of a double‐barrel nanopipette, in which one lumen was used for electroosmotic cytosolic protein delivery and the other was customized for ionic evaluation of the consequence. Upon injection of protein DJ‐1 through the delivery lumen, upregulation of the antioxidant protein could protect neural PC‐12 cells against oxidative stress from phorbol myristate acetate exposure, as deduced by targeting of the cytosolic hydrogen peroxide by the detecting lumen. The nanotool developed in this study for single‐cell protein therapeutics provides a perspective for future single‐cell therapeutics involving different therapeutic modalities, such as peptides, enzymes and nucleic acids. [ABSTRACT FROM AUTHOR]

Single‐cell protein therapeutics is expected to promote our in‐depth understanding of how a specific protein with a therapeutic dosage treats the cell without population averaging. However, it has not yet been tackled by current single‐cell nanotools. We address this challenge by the use of a double‐barrel nanopipette, in which one lumen was used for electroosmotic cytosolic protein delivery and the other was customized for ionic evaluation of the consequence. Upon injection of protein DJ‐1 through the delivery lumen, upregulation of the antioxidant protein could protect neural PC‐12 cells against oxidative stress from phorbol myristate acetate exposure, as deduced by targeting of the cytosolic hydrogen peroxide by the detecting lumen. The nanotool developed in this study for single‐cell protein therapeutics provides a perspective for future single‐cell therapeutics involving different therapeutic modalities, such as peptides, enzymes and nucleic acids. [ABSTRACT FROM AUTHOR]

Herein we report a high-gain signal-on poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) organic electrochemical transistor (OECT) biosensing using an accumulation-mode PEDOT:PSS OECT modulated by a light-fueled MXene/MOFs/NiO Schottky heterojunction. In such a system, the MXene/MOFs/NiO Schottky heterojunction exhibited superior gating effect, as it not only enabled the fast-directional charge transfer but also guaranteed the maximal accessibility of the electrolyte to topped 2D MXene with large surface area. In linkage with a bi-enzyme cascade system, the quinone derivatives produced by the cascade reaction of alkaline phosphatase (ALP) and tyrosinase (TYR) could serve as effective electron acceptors for the representative Ti3C2/PCN-224/NiO heterojunction, underpinning an innovative method for sensitive detection of ALP activity with a low detection limit of 0.001 U L−1. Remarkably, the as-developed system demonstrated a remarkable current gain as high as near 104, which to our knowledge is the highest one among existing OECT biosensory devices. This work represents a generic protocol to develop the novel signal-on PEDOT:PSS OECT platform towards biochemical detection and beyond. [ABSTRACT FROM AUTHOR]

Rational utilization of the rich light‐bio‐matter interplay taking place in single‐cell analysis represents a new technological direction in the field. The light‐fueled operation is expected to achieve advanced photoelectrochemical (PEC) single‐cell analysis with unknown possibilities. Here, a PEC nanoreactor capable of single‐cell sampling and near zero‐background Faradaic detection of intracellular microRNA (miR) is devised by the construction of a small reaction chamber accommodating the target‐triggered hybridization chain reaction for binding the metallointercalator of [Ru(bpy)2(dppz)]2+ as the signal reporter. Light stimulation of the dsDNA/metallointercalator adduct will induce the generation of photocurrents, underpinning a zero‐biased and near zero‐background PEC method toward Faradaic detection of non‐electrogenic miR at the single‐cell level. Using this nanotool, lower miR concentration in the near‐nucleus region than that in the main cytosol was revealed. [ABSTRACT FROM AUTHOR]

Rational utilization of the rich light‐bio‐matter interplay taking place in single‐cell analysis represents a new technological direction in the field. The light‐fueled operation is expected to achieve advanced photoelectrochemical (PEC) single‐cell analysis with unknown possibilities. Here, a PEC nanoreactor capable of single‐cell sampling and near zero‐background Faradaic detection of intracellular microRNA (miR) is devised by the construction of a small reaction chamber accommodating the target‐triggered hybridization chain reaction for binding the metallointercalator of [Ru(bpy)2(dppz)]2+ as the signal reporter. Light stimulation of the dsDNA/metallointercalator adduct will induce the generation of photocurrents, underpinning a zero‐biased and near zero‐background PEC method toward Faradaic detection of non‐electrogenic miR at the single‐cell level. Using this nanotool, lower miR concentration in the near‐nucleus region than that in the main cytosol was revealed. [ABSTRACT FROM AUTHOR]

Herein, we report the rapid mass spectrometric identification of the short-lived intermediates generated under AC electrolysis via combining bipolar electrochemistry with nanoelectrospray ionization in a hybrid ultramicroelectrode/ion emitter. The key reactive intermediates involved in the C–O/O–H cross-metathesis between 4-alkoxy anilines and alcohols were successfully captured and identified for the first time, providing direct evidence for the previously proposed mechanism. [ABSTRACT FROM AUTHOR]

Saccharides play critical roles in many forms of cellular activities. Saccharide structures are however complicated and similar, setting a technical hurdle for direct identification. Nanopores, which are emerging single molecule tools sensitive to minor structural differences between analytes, can be engineered to identity saccharides. A hetero‐octameric Mycobacterium smegmatis porin A nanopore containing a phenylboronic acid was prepared, and was able to clearly identify nine monosaccharide types, including D‐fructose, D‐galactose, D‐mannose, D‐glucose, L‐sorbose, D‐ribose, D‐xylose, L‐rhamnose and N‐acetyl‐D‐galactosamine. Minor structural differences between saccharide epimers can also be distinguished. To assist automatic event classification, a machine learning algorithm was developed, with which a general accuracy score of 0.96 was achieved. This sensing strategy is generally suitable for other saccharide types and may bring new insights to nanopore saccharide sequencing. [ABSTRACT FROM AUTHOR]

Saccharides play critical roles in many forms of cellular activities. Saccharide structures are however complicated and similar, setting a technical hurdle for direct identification. Nanopores, which are emerging single molecule tools sensitive to minor structural differences between analytes, can be engineered to identity saccharides. A hetero‐octameric Mycobacterium smegmatis porin A nanopore containing a phenylboronic acid was prepared, and was able to clearly identify nine monosaccharide types, including D‐fructose, D‐galactose, D‐mannose, D‐glucose, L‐sorbose, D‐ribose, D‐xylose, L‐rhamnose and N‐acetyl‐D‐galactosamine. Minor structural differences between saccharide epimers can also be distinguished. To assist automatic event classification, a machine learning algorithm was developed, with which a general accuracy score of 0.96 was achieved. This sensing strategy is generally suitable for other saccharide types and may bring new insights to nanopore saccharide sequencing. [ABSTRACT FROM AUTHOR]

Acidic catecholamine metabolites, which could serve as diagnostic markers for many diseases, demonstrate an importance of accurate sensing. However, they share a highly similar chemical structure, which is a challenge in the design of sensing strategies. A nanopore may be engineered to sense these metabolites in a single molecule manner. To achieve this, a recently developed programmable nano‐reactor for stochastic sensing (PNRSS) technique adapted with a phenylboronic acid (PBA) adaptor was applied. Three acidic catecholamine metabolites, including 3,4‐dihydroxyphenylacetic acid (DOPAC), 3,4‐dihydroxymandelic acid (DHMA) and 3‐methoxy‐4‐hydroxymandetic acid (VMA) were investigated by PNRSS. Specifically, DHMA, which contains an α‐hydroxycarboxylate moiety and an adjacent cis‐hydroxyl groups on its benzene ring, reports two binding modes simultaneously resolvable by PNRSS. Assisted with the high resolution of PNRSS, direct regulation of these two binding modes by pH can also be observed. A custom machine learning algorithm was also developed to achieve automatic event classification. [ABSTRACT FROM AUTHOR]

By assembling nanotweezers with ATP-splitting aptamers on gold nanorods (AuT123L), we constructed a near-infrared-activated ATP sensing device that could time-controllably image ATP levels in living cells. By replacing the aptamers on the nanotweezers, the nanoplatform can be applied to other important biomolecules, opening up more possibilities for the study of time controllable nanodevices. [ABSTRACT FROM AUTHOR]

Since the concept of surface plasmon amplification by stimulated emission of radiation (SPASER) was proposed in 2003, great progresses have been made on two kinds of plasmonic nanolasers, namely SPASER device and SPASER nanoparticle. In comparison, SPASER nanoparticle, with ultra‐narrow emission line, small size, and good biocompatibility, is a kind of promising luminescent nanoprobe and has a bright application prospect in biomedical imaging and sensing. Hence, it is gradually becoming an attractive research hotspot in the world. However, as the research on SPASER nanoparticle is still in its infancy, there are still lots of problems to be solved before it is widely applied. In this paper, the latest research advances of SPASER nanoparticles and their biological applications are reviewed. Besides existing problems, challenges and opportunities of SPASER nanoparticles as next generation luminescent nanoprobes are discussed as well. [ABSTRACT FROM AUTHOR]

A novel electrochemiluminescence (ECL) Janus emitter realizes dual‐mode biosensing for multiple disease‐related biomarkers from cells. Each Janus emitter consists of ruthenium (II) complex and luminol polymer doped hemispheres that are spatially separated but function simultaneously, generating intense dual‐ECL emissions. This design effectively eliminates optical and electrochemical interferences between different ECL mono‐luminophores in comparison with the homogenous nanostructures, thereby improving ECL efficiency and detection sensitivity. Accordingly, the ECL Janus emitters provide a proof of concept for the construction of the ratiometric ECL sensing of H2O2. Furthermore, this Janus emitter enables simultaneous identification and quantification of the intracellular cancer‐related dual microRNAs. This work not only inspires the development of ECL Janus emitters, but also highlights their potential in bioanalysis and clinical diagnosis in the future. [ABSTRACT FROM AUTHOR]

Photonic (bio)electronic circuits and devices have been an enduring goal in modern photonics and electronics. Organic photoelectrochemical transistor (OPECT) interfacing light with biological world creates a substantial opportunity to this end due to the immense light−bio−matter interplay. Through modulating the invisible ionic circuit of organic electrochemical transistor (OECT) with a bipolar electrode (BPE) accommodating different semiconductor combinations, the unique photonic electronics toward logic and sensor applications are realized. Six combinations of BPEs are produced by the representative n‐type CdS/TiO2 and p‐type BiOI/NiO semiconductors, and the corresponding photonic characteristics and operation rationale are systematically investigated and explained. Designation of opto‐logic circuits and feasibility as a sensory platform are subsequently demonstrated. This work not only represents new photonic bioelectronics but also provides a generic mechanism for the design and development of advanced opto‐logics and bio‐analytics. [ABSTRACT FROM AUTHOR]

Photoelectrochemical (PEC) cytosensors, a combination of the PEC process and the living‐cell assay, have emerged as a powerful tool in the analytical and biological science. This mini review provides a brief introduction of this arena and summaries the key steps about the development of PEC cytosensors with representative examples, followed by future prospects based on our own opinions. [ABSTRACT FROM AUTHOR]

Two new hasubanan alkaloids, stephalonester A (1) and stephalonester B (2), together with four known compounds, stephalonine E (3), longanone (4), cephatonine (5), and prostephabyssine (6) were isolated from the whole plant of Stephania longa. Their structures were determined by HR-ESI-MS, 1 D and 2 D NMR, ECD calculations, as well as by comparison with literature values. All compounds were evaluated for their anti-inflammatory activity in vitro. Compounds 4, 5, and 6 exhibited significantly inhibitory effects on TNF-α and IL-6 production with IC50 values range from 6.54 to 30.44 µM. [ABSTRACT FROM AUTHOR]

Nanozymes with cascade catalytic reactions gain advantages over natural enzymes by simplifying the preparation, decreasing the cost, and enhancing the local concentrations of the intermediates and the stability. However, in vivo applications of such cascade nanozymes are hampered due to the low catalytic activity in the complex physiological microenvironment. Substantial research work is currently devoted to exploiting light-driven catalytic kinetic acceleration of nanozymes via hot electron injection from plasmonic nanoparticles. Here, a near-infrared (NIR) light-driven plasmon-enhanced cascade nanozyme with a formulation of Au@Pt0.46Ag0.54 is developed for efficient synergistic cancer therapy. This nanozyme possesses catalase, oxidase, and peroxidase activities and is capable of converting hydrogen peroxide to oxygen and reactive oxygen species through cascade reactions. Both in vitro and in vivo experimental measurements reveal that 808 nm NIR-laser-driven hot electron injection not only obviously enhanced the catalytic activities of the nanozyme but also triggered efficient photothermal conversion, which successfully achieved synergetic catalytic therapy/photothermal therapy for cancer treatment. This strategy of tailoring multi-metal cascade nanozyme techniques opens up avenues for realizing multistep reactions with high catalytic kinetics and provides an innovative way for therapeutic systems with clinical significance. [ABSTRACT FROM AUTHOR]

A large collection of unique molecular barcodes is useful in the simultaneous sensing or screening of molecular analytes. Though the sequence of DNA has been widely applied to encode for molecular barcodes, decoding of these barcodes is normally assisted by sequencing. We here demonstrate a barcode system based solely on self‐assembly of synthetic nucleic acids and direct nanopore decoding. Each molecular barcode is composed of "n" distinct information nodes in a non‐binary manner and can be sequentially scanned and decoded by a Mycobacterium smegmatis porin A (MspA) nanopore. Nanopore events containing step‐shaped features were consistently reported. 14 unique information nodes were developed which in principle could encode for 14n unique molecular barcodes in a barcode containing "n" information nodes. These barcode probes were adapted to detect different antibody proteins or cancer‐related microRNAs, suggesting their immediate application in a wide variety of sensing applications. [ABSTRACT FROM AUTHOR]

A large collection of unique molecular barcodes is useful in the simultaneous sensing or screening of molecular analytes. Though the sequence of DNA has been widely applied to encode for molecular barcodes, decoding of these barcodes is normally assisted by sequencing. We here demonstrate a barcode system based solely on self‐assembly of synthetic nucleic acids and direct nanopore decoding. Each molecular barcode is composed of "n" distinct information nodes in a non‐binary manner and can be sequentially scanned and decoded by a Mycobacterium smegmatis porin A (MspA) nanopore. Nanopore events containing step‐shaped features were consistently reported. 14 unique information nodes were developed which in principle could encode for 14n unique molecular barcodes in a barcode containing "n" information nodes. These barcode probes were adapted to detect different antibody proteins or cancer‐related microRNAs, suggesting their immediate application in a wide variety of sensing applications. [ABSTRACT FROM AUTHOR]

We report a photodynamic therapy driven by electrochemiluminescence (ECL). The luminescence generated by Ru(bpy)32+ and co‐reactant tripropylamine (TPA) pair acts as both optical readout for ECL imaging, and light source for the excitation of photosensitizer to produce reactive oxygen species (ROS) in photodynamic therapy (PDT) system. The ECL‐driven PDT (ECL‐PDT) relies on the effective energy transfer from ECL emission to photosensitizer chlorin e6 (Ce6), which sensitizes the surrounding O2 into ROS. The dynamic process of gradual morphological changes, the variation of cell‐matrix adhesions, as well as the increase of cell membrane permeability in the process of ECL‐PDT were monitored under ECL microscopy (ECLM) with good spatiotemporal resolution. Combining real‐time imaging with ECL‐PDT, this new strategy provides not only new insights into dynamic cellular processes, but also promising potential of ECL in clinical applications. [ABSTRACT FROM AUTHOR]

We report a photodynamic therapy driven by electrochemiluminescence (ECL). The luminescence generated by Ru(bpy)32+ and co‐reactant tripropylamine (TPA) pair acts as both optical readout for ECL imaging, and light source for the excitation of photosensitizer to produce reactive oxygen species (ROS) in photodynamic therapy (PDT) system. The ECL‐driven PDT (ECL‐PDT) relies on the effective energy transfer from ECL emission to photosensitizer chlorin e6 (Ce6), which sensitizes the surrounding O2 into ROS. The dynamic process of gradual morphological changes, the variation of cell‐matrix adhesions, as well as the increase of cell membrane permeability in the process of ECL‐PDT were monitored under ECL microscopy (ECLM) with good spatiotemporal resolution. Combining real‐time imaging with ECL‐PDT, this new strategy provides not only new insights into dynamic cellular processes, but also promising potential of ECL in clinical applications. [ABSTRACT FROM AUTHOR]

Single‐nanoparticle electrochemistry offers electrochemical behaviors of individual entities beyond the ensemble system. An electric double layer (EDL) exists on any charged particle–liquid interface because of counter‐ion accumulation, while direct measuring of the interfacial ion migration remains a challenge. Herein, a plasmonic‐based transient microscopic method, with a temporal resolution of 1–2 μs, was demonstrated to directly track the ion migration dynamics on single charged nanoparticles. We found that the dynamics of EDL formation might deviate significantly from the prediction made by using the classical resistance–capacitance (RC) model under nanoscale and transient conditions. Under ultrafast charging, due to the limit migration rate of ions in the solution, the actual time scale of the EDL formation could be up to 5 times slower than the predicted value from the RC model. We then proposed a new theoretical model to describe the transient dynamics of EDL formation. These results may expand our current knowledge about nano‐electrochemistry and transient electrochemistry. [ABSTRACT FROM AUTHOR]

Single‐nanoparticle electrochemistry offers electrochemical behaviors of individual entities beyond the ensemble system. An electric double layer (EDL) exists on any charged particle–liquid interface because of counter‐ion accumulation, while direct measuring of the interfacial ion migration remains a challenge. Herein, a plasmonic‐based transient microscopic method, with a temporal resolution of 1–2 μs, was demonstrated to directly track the ion migration dynamics on single charged nanoparticles. We found that the dynamics of EDL formation might deviate significantly from the prediction made by using the classical resistance–capacitance (RC) model under nanoscale and transient conditions. Under ultrafast charging, due to the limit migration rate of ions in the solution, the actual time scale of the EDL formation could be up to 5 times slower than the predicted value from the RC model. We then proposed a new theoretical model to describe the transient dynamics of EDL formation. These results may expand our current knowledge about nano‐electrochemistry and transient electrochemistry. [ABSTRACT FROM AUTHOR]