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Exocytosis involving the fusion of intracellular vesicles with cell membrane, is thought to be modulated by the mechanical cues in the microenvironment. Single‐cell electrochemistry can offer unique information about the quantification and kinetics of exocytotic events; however, the effects of mechanical force on vesicular release have been poorly explored. Herein, we developed a stretchable microelectrode with excellent electrochemical stability under mechanical deformation by microfabrication of functionalized poly(3,4‐ethylenedioxythiophene) conductive ink, which achieved real‐time quantitation of strain‐induced vesicular exocytosis from a single cell for the first time. We found that mechanical strain could cause calcium influx via the activation of Piezo1 channels in chromaffin cell, initiating the vesicular exocytosis process. Interestingly, mechanical strain increases the amount of catecholamines released by accelerating the opening and prolonging the closing of fusion pore during exocytosis. This work is expected to provide revealing insights into the regulatory effects of mechanical stimuli on vesicular exocytosis. [ABSTRACT FROM AUTHOR]

The glutathione (GSH) system is one of the most powerful intracellular antioxidant systems for the elimination of reactive oxygen species (ROS) and maintaining cellular redox homeostasis. However, the rapid kinetics information (at the millisecond to the second level) during the dynamic antioxidation process of the GSH system remains unclear. As such, we specifically developed a novel dual‐wire nanosensor (DWNS) that can selectively and synchronously measure the levels of GSH and ROS with high temporal resolution, and applied it to monitor the transient ROS generation as well as the rapid antioxidation process of the GSH system in individual cancer cells. These measurements revealed that the glutathione peroxidase (GPx) in the GSH system is rapidly initiated against ROS burst in a sub‐second time scale, but the elimination process is short‐lived, ending after a few seconds, while some ROS are still present in the cells. This study is expected to open new perspectives for understanding the GSH antioxidant system and studying some redox imbalance‐related physiological. [ABSTRACT FROM AUTHOR]

Nanochannel technology has emerged as a powerful tool for label‐free and highly sensitive detection of protein folding/unfolding status. However, utilizing the inner walls of a nanochannel array may cause multiple events even for proteins with the same conformation, posing challenges for accurate identification. Herein, we present a platform to detect unfolded proteins through electrical and optical signals using nanochannel arrays with outer‐surface probes. The detection principle relies on the specific binding between the maleimide groups in outer‐surface probes and the protein cysteine thiols that induce changes in the ionic current and fluorescence intensity responses of the nanochannel array. By taking advantage of this mechanism, the platform has the ability to differentiate folded and unfolded state of proteins based on the exposure of a single cysteine thiol group. The integration of these two signals enhances the reliability and sensitivity of the identification of unfolded protein states and enables the distinction between normal cells and Huntington's disease mutant cells. This study provides an effective approach for the precise analysis of proteins with distinct conformations and holds promise for facilitating the diagnoses of protein conformation‐related diseases. [ABSTRACT FROM AUTHOR]

Perovskite quantum dots (PQDs) have attracted much attention in the field of photoelectrochemical (PEC) sensors owing to their superb optical properties and efficient charge transport, but the inherent poor stability severely hinders their PEC applications. Herein, hydrolysis‐resistant CsPbBr3/reduced graphene oxide nanoscrolls (CsPbBr3/rGO NSs) are obtained by solvent‐assisted self‐rolling process toward water‐stable PEC sensors. CsPbBr3 QDs embedded in rGO nanosheets can be prevented from water since the multilayer rGO shell layers, which maintains excellent optical properties. On account of strong interfacial interactions, rGO nanosheets are crimped spontaneously with CsPbBr3 QDs, which offer access to superb structural and long‐term storage stability. Moreover, appropriate band alignment and ultrafast interfacial carrier transfer enable CsPbBr3/rGO NSs to exhibit greatly enhanced anode photocurrent response for subsequent PEC sensing. As a demonstration, the molecular imprinted PEC sensors for two kinds of mycotoxins (aflatoxin B1 or ochratoxin A) presents an ultra‐high sensitivity and good anti‐interference ability. Significantly, this work provides an inspirable and convenient route for hydrolysis‐resistant PQDs‐based optoelectronic and photoelectrocatalytic applications in aqueous ambience. [ABSTRACT FROM AUTHOR]

Saponins extracted from Panax notoginseng leaves by methanol or water could be orally administrated for insomnia with very low bioavailability, which might be bio‐converted by gut microbiota to generate potential bioactive products. Moreover, gut microbiota profiles from insomniac patients are very different from healthy subjects. We aimed to compare the metabolic characteristics and profiles of the two saponins extract by incubation with gut microbiota from insomniac patients. The ginsenosides, notoginsenosides, and metabolites were identified and relatively quantified by high‐performance liquid chromatography‐tandem mass spectrometry. Gut microbiota was profiled by 16S ribosomal RNA gene sequencing. The results showed that saponins were very different between methanol or water extract groups, which were metabolized by gut microbiota to generate similar yields. The main metabolites included ginsenoside Rd, ginsenoside F2, ginsenoside C‐Mc or ginsenoside C‐Y, ginsenoside C‐Mx, ginsenoside compound K, and protopanaxadiol in both groups, while gypenoside XVII, notoginsenoside Fe, ginsenoside Rd2, and notoginsenoside Fd were the intermediates in the methanol group. Moreover, the microbial, Faecalibacterium prausnitzi, could bio‐convert the saponins to obtain the corresponding metabolites. Our study implied that saponins extracted from P. notoginseng leaves by methanol or water could be used for insomniac patients due to gut microbiota biotransformation. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Electrochemical sensing faces huge challenges in characterizing the transient release of biochemical molecules from deformed cells, due to the severely mechanical mismatch between rigid electrodes and soft cells. In recent years, the emergence of stretchable electrochemical sensors has made a breakthrough by complying with the deformation of living cells and simultaneous monitoring of mechanically evoked biochemical signals. This review first summarizes two fundamental strategies for the fabrication of stretchable electrodes from the points of structure and material. Next, recent progresses in construction of functionalized interface to improve the performance of stretchable electrochemical sensors are presented. Then, the application of stretchable electrochemical sensors in real‐time monitoring of biomolecules released by mechanically sensitive cells is introduced. Finally, some perspectives and challenges of stretchable electrochemical sensors regarding cell detection are discussed. What is the favorite and original chemistry developed in your research group? The design and construction of electrochemical sensing platform for real‐time monitoring of life activities. What is the most important personality for scientific research? Innovative spirit, strong curiosity and persistence. How do you supervise your students? Encourage students to think much and eager to innovate. What are your hobbies? I like music and playing badminton. Who influences you mostly in your life? My family and collaborators. Could you please give us some advices on improving Chinese Journal of Chemistry? Focusing on the originality of the manuscript. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Electrochemical sensing faces huge challenges in characterizing the transient release of biochemical molecules from deformed cells, due to the severely mechanical mismatch between rigid electrodes and soft cells. In recent years, the emergence of stretchable electrochemical sensors has made a breakthrough by complying with the deformation of living cells and simultaneous monitoring of mechanically evoked biochemical signals. This review first summarizes two fundamental strategies for the fabrication of stretchable electrodes from the points of structure and material. Next, recent progresses in construction of functionalized interface to improve the performance of stretchable electrochemical sensors are presented. Then, the application of stretchable electrochemical sensors in real‐time monitoring of biomolecules released by mechanically sensitive cells is introduced. Finally, some perspectives and challenges of stretchable electrochemical sensors regarding cell detection are discussed. What is the favorite and original chemistry developed in your research group? The design and construction of electrochemical sensing platform for real‐time monitoring of life activities. What is the most important personality for scientific research? Innovative spirit, strong curiosity and persistence. How do you supervise your students? Encourage students to think much and eager to innovate. What are your hobbies? I like music and playing badminton. Who influences you mostly in your life? My family and collaborators. Could you please give us some advices on improving Chinese Journal of Chemistry? Focusing on the originality of the manuscript. [ABSTRACT FROM AUTHOR]

Rare circulating tumor cells (CTCs) are always harvested with large numbers of white blood cells (WBCs) by current CTC isolation techniques, which influences the accuracy of CTC‐related gene and protein analysis. Therefore, it is very urgent to develop a method for efficient isolation of CTCs with high purity. In this work, we fabricated a reversibly assembled interface by layer‐by‐layer assembly of biotinylated poly‐(L‐lysine‐graft‐ethylene glycol) (PLL‐g‐PEG‐biotin), streptavidin, and CTC‐specific antibody on a three‐dimensional conductive scaffold, and further embedded it into a customized microchip for CTC capture. The assembled multilayers increased the roughness of the scaffold, which improved the capture efficiency. Importantly, the PLL‐g‐PEG‐biotin covalently coupled with CTCs could be detached from the scaffold by electrostatic repulsion, and the released CTCs could be recaptured on the conductive scaffold via electrostatic attraction while the WBCs were continuously drifted away. This reversible capture and release strategy significantly improved the purity of CTCs, and pure CTCs were obtained from cancer patients' blood samples for gene mutation assay, which will be of great significance for assisting cancer diagnosis and treatment in a noninvasive way. [ABSTRACT FROM AUTHOR]

Many cells in vivo have their inherent motions, which involve numerous biochemical and biophysical signals synergistically regulating cell behavior and function. However, existing methods offer little information about the concurrently chemical and physical responses of dynamically pulsing cells. Here, we report a soft electrode with an electrospun poly(3,4‐ethylenedioxythiophene) (PEDOT)‐based nanomesh to fully comply with spontaneous motions of cells. Moreover, this electrode demonstrated excellent electrical conductivity, electrochemical performance and cellular biocompatibility. Cardiomyocytes cultured thereon exhibited autonomous and rhythmic contractility, and synchronously induced mechanical deformation of the underlying electrode, which allowed real‐time monitoring of nitric oxide release and electrophysiological activity of cardiomyocytes. This work provides a promising way toward recording chemical and electrical signals of biological systems with their natural motions. [ABSTRACT FROM AUTHOR]

The current strategies for nanoelectrode functionalization usually involve sophisticated modification procedures, uncontrollable and unstable modifier assembly, as well as a limited variety of modifiers. To address this issue, we propose a versatile strategy for large‐scale synthesis of biomimetic molecular catalysts (BMCs) modified nanowires (NWs) to construct functionalized electrochemical nanosensors. This design protocol employs an easy, controllable and stable assembly of diverse BMCs‐poly(3,4‐ethylenedioxythiophene) (PEDOT) composites on conductive NWs. The intrinsic catalytic activity of BMCs combined with outstanding electron transfer ability of conductive polymer enables the nanosensors to sensitively and selectively detect various biomolecules. Further application of sulfonated cobalt phthalocyanine functionalized nanosensors achieves real‐time electrochemical monitoring of intracellular glutathione levels and its redox homeostasis in single living cells for the first time. [ABSTRACT FROM AUTHOR]

A strategy for one‐pot and large‐scale synthesis of functionalized core–shell nanowires (NWs) to high‐efficiently construct single nanowire electrodes is proposed. Based on the polymerization reaction between 3,4‐ethylenedioxythiophene (EDOT) and noble metal cations, manifold noble metal nanoparticles‐polyEDOT (PEDOT) nanocomposites can be uniformly modified on the surface of any nonconductive NWs. This provides a facile and versatile approach to produce massive number of core–shell NWs with excellent conductivity, adjustable size, and well‐designed properties. Nanoelectrodes manufactured with such core–shell NWs exhibit excellent electrochemical performance and mechanical stability as well as favorable antifouling properties, which are demonstrated by in situ intracellular monitoring of biological molecules (nitric oxide) and unraveling its relevant unclear signaling pathway inside single living cells. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Parkinson's disease (PD) is one of the most common neurogenerative diseases (NDDs), characterized as less neurotransmitter release and loss of dopaminergic (DAergic) neurons with microglial inflammatory response as a key player. Natural product harpagide with anti‐inflammatory function is a potential therapeutic drug of PD, but its role towards microglial activation and inflammation‐mediated neuronal injury remained unsure. In this work, taking advantage of nanoelectrode amperometry with high temporal‐spatial resolution, we used nanowire electrodes (NWEs) to monitor intracellular reactive oxygen species (ROS) level and carbon fiber nanoelectrodes (CFNEs) to detect synaptic dopamine exocytosis, to explore the effect of harpagide in modulating microglial inflammatory reaction and protecting DAergic neurons in neuron‐microglia co‐culture system. The results indicate that harpagide inhibits microglia from activation induced by LPS/IFN‐γ and generation of ROS, therefore reduces inflammation‐mediated neural injury and maintains dopamine exocytosis function. These conclusions establish that harpagide possesses promising avenues for preventive or therapeutic interventions against PD and other NDDs. [ABSTRACT FROM AUTHOR]

Quantitative measurements of intravesicular glutamate (Glu) and of transient exocytotic release contents directly from individual living neurons are highly desired for understanding the mechanisms (full or sub‐quantal release?) of synaptic transmission and plasticity. However, this could not be achieved so far due to the lack of adequate experimental strategies relying on selective and sensitive Glu nanosensors. Herein, we introduce a novel electrochemical Glu nanobiosensor based on a single SiC nanowire that can selectively measure in real‐time Glu fluxes released via exocytosis by large Glu vesicles (ca. 125 nm diameter) present in single hippocampal axonal varicosities as well as their intravesicular content before exocytosis. These measurements revealed a sub‐quantal release mode in living hippocampal neurons, viz. only ca. one third to one half of intravesicular Glu molecules are released by individual vesicles during exocytotic events. Importantly, this fraction remained practically the same when hippocampal neurons were pretreated with L‐Glu‐precursor L‐glutamine, while it significantly increased after zinc treatment, although in both cases the intravesicular contents were drastically affected. [ABSTRACT FROM AUTHOR]

In the field of three‐dimensional (3D) cell culture and tissue engineering, great advance focusing on functionalized materials and desirable culture systems has been made to mimic the natural environment of cells in vivo. Mechanical loading is one of the critical factors that affect cell/tissue behaviors and metabolic activities, but the reported models or detection methods offer little direct and real‐time information about mechanically induced cell responses. Herein, for the first time, a stretchable and multifunctional platform integrating 3D cell culture, mechanical loading, and electrochemical sensing is developed by immobilization of biomimetic peptide linked gold nanotubes on porous and elastic polydimethylsiloxane. The 3D scaffold demonstrates very good compatibility, excellent stretchability, and stable electrochemical sensing performance. This allows mimicking the articular cartilage and investigating its mechanotransduction by 3D culture, mechanical stretching of chondrocytes, and synchronously real‐time monitoring of stretch‐induced signaling molecules. The results disclose a previously unclear mechanotransduction pathway in chondrocytes that mechanical loading can rapidly activate nitric oxide signaling within seconds. This indicates the promising potential of the stretchable 3D sensing in exploring the mechanotransduction in 3D cellular systems and engineered tissues. [ABSTRACT FROM AUTHOR]

Electrochemical sensing based on conventional rigid electrodes has great restrictions for characterizing biomolecules in deformed cells or soft tissues. The recent emergence of stretchable sensors allows electrodes to conformally contact to curved surfaces and perfectly comply with the deformation of living cells and tissues. This provides a powerful strategy to monitor biomolecules from mechanically deformed cells, tissues, and organisms in real time, and opens up new opportunities to explore the mechanotransduction process. In this minireview, we first summarize the fabrication of stretchable electrodes with emphasis on the nanomaterial‐enabled strategies. We then describe representative applications of stretchable sensors in the real‐time monitoring of mechanically sensitive cells and tissues. Finally, we present the future possibilities and challenges of stretchable electrochemical sensing in cell, tissue, and in vivo detection. [ABSTRACT FROM AUTHOR]

The role of endogenous serotonin (5‐HT) in gastrointestinal motility is still highly controversial. Although electrochemical techniques allow for direct and real‐time recording of biomolecules, the dynamic monitoring of 5‐HT release from elastic and tubular intestine during motor reflexes remains a great challenge because of the specific peristalsis patterns and inevitable passivation of the sensing interface. A stretchable sensor with antifouling and decontamination properties was assembled from gold nanotubes, titanium dioxide nanoparticles, and carbon nanotubes. The sandwich‐like structure endowed the sensor with satisfying mechanical stability and electrochemical performance, high resistance against physical adsorption, and superior efficiency in the photodegradation of biofouling molecules. Insertion of the sensor into the lumen of rat ileum (the last section of the small intestine) successfully mimics intestinal peristalsis, and simultaneous real‐time monitoring of distension‐evoked 5‐HT release was possible for the first time. Our results unambiguously reveal that mechanical distension of the intestine induces endogenous 5‐HT overflow, and 5‐HT level is closely associated with the physiological or pathological states of the intestine. [ABSTRACT FROM AUTHOR]

The existence of a homeostatic mechanism regulating reactive oxygen/nitrogen species (ROS/RNS) amounts inside phagolysosomes has been invoked to account for the efficiency of this process but could not be unambiguously documented. Now, intracellular electrochemical analysis with platinized nanowire electrodes (Pt‐NWEs) allowed monitoring ROS/RNS effluxes with sub‐millisecond resolution from individual phagolysosomes impacting onto the electrode inserted inside a living macrophage. This shows for the first time that the consumption of ROS/RNS by their oxidation at the nanoelectrode surface stimulates the production of significant ROS/RNS amounts inside phagolysosomes. These results establish the existence of the long‐postulated ROS/RNS homeostasis and allows its kinetics and efficiency to be quantified. ROS/RNS concentrations may then be maintained at sufficiently high levels for sustaining proper pathogen digestion rates without endangering the macrophage internal structures. [ABSTRACT FROM AUTHOR]

A method for the preparation of chiral triarylmethanes via organocatalytic 1,6‐addition of arylboronic acids to para‐quinone methides (p‐QMs) was established. Here the use of salicylaldehyde‐derived p‐QMs with an ortho‐hydroxy substituent as a directing group was essential for the remote stereocontrol. In the presence of a BINOL catalyst, chiral triarylmethanes can be obtained in high yields (up to 99%) with excellent enantioselectivities (up to 99% ee). This method shows broad substrate tolerance and can be easily scaled up, both electron‐rich and electron‐deficient arylboronic acids are suitable substrates for this addition reaction. [ABSTRACT FROM AUTHOR]

Abstract: Glutamate (Glu) is recognized as a vital neurotransmitter released via vesicular exocytosis and plays important roles in many physiological processes. Microelectrode amperometry has become a powerful method to study the secreted electroactive biochemicals via exocytosis, however, there was no means for direct monitoring of exocytosis of the non‐electroactive Glu so far. Herein, we developed an enzymatic micro‐biosensor by co‐modification of glutamate oxidase (GluOx) and Pt nanoparticles (Pt NPs) on the surface of a carbon fiber microelectrode. The Glu was enzymatically transformed by GluOx to an electroactive product, H2O2, which was then electrochemically detected by the Pt NPs. The prominent catalytic activity of enzyme and micrometer scale of microelectrode endow the sensor with high sensitivity and spatio‐temporal resolution, allowing real‐time monitoring Glu exocytosis from single hippocampal varicosities. The results demonstrate the capability of this biosensor in monitoring and quantification of the quantal release of neurotransmitter Glu, indicating its great potential in exploring the cellular mechanism of neuron communication and synaptic plasticity. [ABSTRACT FROM AUTHOR]

Nanoelectrodes allow precise and quantitative measurements of important biological processes at the single living-cell level in real time. Cylindrical nanowire electrodes (NWEs) required for intracellular measurements create a great challenge for achieving excellent electrochemical and mechanical performances. Herein, we present a facile and robust solution to this problem based on a unique SiC-core-shell design to produce cylindrical NWEs with superior mechanical toughness provided by the SiC nano-core and an excellent electrochemical performance provided by the ultrathin carbon shell that can be used as such or platinized. The use of such NWEs for biological applications is illustrated by the first quantitative measurements of ROS/RNS in individual phagolysosomes of living macrophages. As the shell material can be varied to meet any specific detection purpose, this work opens up new opportunities to monitor quantitatively biological functions occurring inside cells and their organelles. [ABSTRACT FROM AUTHOR]

Existing methods offer little direct and real-time information about stretch-triggered biochemical responses during cell mechanotransduction. A novel stretchable electrochemical sensor is reported that takes advantage of a hierarchical percolation network of carbon nanotubes and gold nanotubes (CNT-AuNT). This hybrid nanostructure provides the sensor with excellent time-reproducible mechanical and electrochemical performances while granting very good cellular compatibility, making it perfectly apt to induce and monitor simultaneously transient biochemical signals. This is validated by monitoring stretch-induced transient release of small signaling molecules by both endothelial and epithelial cells cultured on this sensor and submitted to stretching strains of different intensities. This work demonstrates that the hybrid CNT-AuNT platform offers a versatile and highly sensitive way to characterize and quantify short-time mechanotransduction responses. [ABSTRACT FROM AUTHOR]

Real-time and in situ monitoring of H2S in biological systems has become crucial, but faces big challenges as H2S has been identified as an important endogenous gas signaling molecule. Herein, we prepare a poly(3,4-ethylenedioxythiophene) (PEDOT)-modified nanoporous gold (NPG) microelectrode for the electrochemical detection of H2S. The NPG framework possesses excellent conductivity, a 3D porous structure, and a large specific area. The PEDOT sensing film effectively retards electrode fouling during the detection, which ensures a stable response towards H2S over the range of interest. The synergetic properties of the NPG scaffold and the PEDOT sensing films endow the microelectrode with high sensitivity and a fast response, thus allowing H2S release from single cells to be monitored. This work represents the first step toward real-time electrochemical monitoring of H2S from single cells, thereby potentially facilitating future studies to better understand the function of H2S in biological and pathological processes. [ABSTRACT FROM AUTHOR]

The root of Oplopanax elatus (Nakai) Nakai has a well-known history of use for the treatment of diseases such as neurasthenia, cardiovascular disorders, and cancer by the native people in northeast China. It is important to screen and identify the bioactive molecules from its root rapidly. Hereby, an off-line two-dimensional high performance liquid chromatography coupled with diode array detection and tandem time-of-flight mass spectrometry together with 2,2ʹ-diphenyl-1-picrylhydrazyl was established to screen antioxidants from the root of O. elatus. A Waters cyanogen column (150 × 3.9 mm, id, 4 μm) was used for the first dimensional liquid chromatography, while a Hypersil BDS-C18 column (250 × 4.6 mm, id, 5 μm) was installed for the second dimension liquid chromatographic analysis. Twenty-eight compounds had been tentatively identified from the methanol extract of the air-dried root of O. elatus including six polyynes and eight phenolic derivatives were screened with antioxidant activity. The developed method could be expedient for screening and identifying antioxidants from O. elatus. [ABSTRACT FROM AUTHOR]

Stretchable electrochemical sensors are conceivably a powerful technique that provides important chemical information to unravel elastic and curvilinear living body. However, no breakthrough was made in stretchable electrochemical device for biological detection. Herein, we synthesized Au nanotubes (NTs) with large aspect ratio to construct an effective stretchable electrochemical sensor. Interlacing network of Au NTs endows the sensor with desirable stability against mechanical deformation, and Au nanostructure provides excellent electrochemical performance and biocompatibility. This allows for the first time, real-time electrochemical monitoring of mechanically sensitive cells on the sensor both in their stretching-free and stretching states as well as sensing of the inner lining of blood vessels. The results demonstrate the great potential of this sensor in electrochemical detection of living body, opening a new window for stretchable electrochemical sensor in biological exploration. [ABSTRACT FROM AUTHOR]

Electrode fouling and passivation is a substantial and inevitable limitation in electrochemical biosensing, and it is a great challenge to efficiently remove the contaminant without changing the surface structure and electrochemical performance. Herein, we propose a versatile and efficient strategy based on photocatalytic cleaning to construct renewable electrochemical sensors for cell analysis. This kind of sensor was fabricated by controllable assembly of reduced graphene oxide (RGO) and TiO2 to form a sandwiching RGO@TiO2 structure, followed by deposition of Au nanoparticles (NPs) onto the RGO shell. The Au NPs-RGO composite shell provides high electrochemical performance. Meanwhile, the encapsulated TiO2 ensures an excellent photocatalytic cleaning property. Application of this renewable microsensor for detection of nitric oxide (NO) release from cells demonstrates the great potential of this strategy in electrode regeneration and biosensing. [ABSTRACT FROM AUTHOR]

Chemical synaptic transmission is central to the brain functions. In this regard, real-time monitoring of chemical synaptic transmission during neuronal communication remains a great challenge. In this work, in vivo-like oriented neural networks between superior cervical ganglion (SCG) neurons and their effector smooth muscle cells (SMC) were assembled in a microfluidic device. This allowed amperometric detection of individual neurotransmitter release events inside functional SCG-SMC synapse with carbon fiber nanoelectrodes as well as recording of postsynaptic potential using glass nanopipette electrodes. The high vesicular release activities essentially involved complex events arising from flickering fusion pores as quantitatively established based on simulations. This work allowed for the first time monitoring in situ chemical synaptic transmission under conditions close to those found in vivo, which may yield important and new insights into the nature of neuronal communications. [ABSTRACT FROM AUTHOR]

Chemical synaptic transmission is central to the brain functions. In this regard, real-time monitoring of chemical synaptic transmission during neuronal communication remains a great challenge. In this work, in vivo-like oriented neural networks between superior cervical ganglion (SCG) neurons and their effector smooth muscle cells (SMC) were assembled in a microfluidic device. This allowed amperometric detection of individual neurotransmitter release events inside functional SCG-SMC synapse with carbon fiber nanoelectrodes as well as recording of postsynaptic potential using glass nanopipette electrodes. The high vesicular release activities essentially involved complex events arising from flickering fusion pores as quantitatively established based on simulations. This work allowed for the first time monitoring in situ chemical synaptic transmission under conditions close to those found in vivo, which may yield important and new insights into the nature of neuronal communications. [ABSTRACT FROM AUTHOR]

Four new phenolic derivatives, including two phenylpropanoid glycosides, one benzoate glycoside, and one lignan glycoside, together with one known glyceride, were isolated from the root bark of Oplopanax horridus. The structures of the new compounds were elucidated as 3-{4-[(6- O-acetyl- β- D-glucopyranosyl)oxy]-3,5-dimethoxyphenyl}propanoic acid ( 1), (+)-[5,6,7,8-tetrahydro-7-(hydroxymethyl)-10,11-dimehoxydibenzo[ a, c][8]annulen-6-yl]methyl β- D-glucopyranoside ( 2), (+)-methyl 4-[6- O-{3-hydroxy-3-methyl-5-(1-methylpropyl)oxy]-5-oxopentanoyl}-4- O-( β- D-glucopyranosyl)- β- D-glucopyranosyl)oxy]-3-methoxybenzoate ( 3), and 2-methoxy-4-[(1 E)-3-methoxy-3-oxoprop-1-en-1-yl]phenyl 6- O-{3-hydroxy-3-methyl-5-[(1-methylpropyl)oxy]-5-oxopentanoyl-4- O- β- d-glucopyranosyl- β- d-glucopyranoside ( 4) on the basis of spectroscopic techniques including NMR and MS analyses. The known compound was identified as glycer-2-yl ferulate ( 5) by comparing its physical and spectral data with those reported in the literature. [ABSTRACT FROM AUTHOR]

Recent biochemical results suggest that auxin (IAA) efflux is mediated by a vesicular cycling mechanism, but no direct detection of vesicular IAA release from single plant cells in real-time has been possible up to now. A TiC@C/Pt-QANFA micro-electrochemical sensor has been developed with high sensitivity in detection of IAA, and it allows real-time monitoring and quantification of the quantal release of auxin from single plant protoplast by exocytosis. [ABSTRACT FROM AUTHOR]

The Inside Cover picture shows the synergetic properties of poly(3,4‐ethylenedioxythiophene)(PEDOT)‐modified nanoporous gold (NPG), which endow the microelectrode with high sensitivity and a fast response for the electrochemical detection of H2S, thus allowing H2S release from single cells to be monitored in real time. More details can be found in the Communication by W.‐H‐ Huang and co‐workers on page 1998 in Issue 12, 2016 (DOI: 10.1002/celc.201600411). [ABSTRACT FROM AUTHOR]

Review: 86 refs. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Parkinson's disease (PD) is one of the most common neurogenerative diseases (NDDs), characterized as less neurotransmitter release and loss of dopaminergic (DAergic) neurons with microglial inflammatory response as a key player. Natural product harpagide with anti‐inflammatory function is a potential therapeutic drug of PD, but its role towards microglial activation and inflammation‐mediated neuronal injury remained unsure. In this work, taking advantage of nanoelectrode amperometry with high temporal‐spatial resolution, we used nanowire electrodes (NWEs) to monitor intracellular reactive oxygen species (ROS) level and carbon fiber nanoelectrodes (CFNEs) to detect synaptic dopamine exocytosis, to explore the effect of harpagide in modulating microglial inflammatory reaction and protecting DAergic neurons in neuron‐microglia co‐culture system. The results indicate that harpagide inhibits microglia from activation induced by LPS/IFN‐γ and generation of ROS, therefore reduces inflammation‐mediated neural injury and maintains dopamine exocytosis function. These conclusions establish that harpagide possesses promising avenues for preventive or therapeutic interventions against PD and other NDDs. [ABSTRACT FROM AUTHOR]