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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]

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]

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]

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]

Conventional photoelectrochemical (PEC) analysis mostly utilizes photoactive material modified planar indium tin oxides (ITOs) to obtain photocurrent responses for the measurement of analytes in solution. In this work, a CdS quantum dot (QD) modified nanopipette was prepared for the PEC analysis of the alkaline phosphatase (ALP) activity in single MCF-7 cells. The nanopipette was filled with ascorbic acid 2-phosphate (AAP) that was egressed outside the nanopipette by electrochemical pumping. Next, AAP was catalyzed by ALP to generate ascorbic acid (AA), which is an efficient electron donor for CdS QDs under illumination. Based on the result that the nanopipette showed a linear photocurrent response to AA, a nearly linear correlation between the photocurrent and the activity of ALP was established. Accordingly, using these CdS QD modified nanopipettes, the ALP activity in single MCF-7 cells was determined to be 0.12 U mL−1 by PEC analysis. This work does not expand the application of PEC bioanalysis, but offers a new strategy for single cell analysis. [ABSTRACT FROM AUTHOR]

Based on the nonlinear plasmonic scattering response to the modulated excitation in time, we realized a single-wavelength super-resolution imaging method on a custom-built system which is named as a scattering saturation STED (ssSTED) microscope. A spatial resolution of λ/7 (65 nm) was obtained on 50 nm gold nanoparticles. [ABSTRACT FROM AUTHOR]

Drop-on-demand microkits with a diameter of ∼20 μm are used to measure the activity of acetylcholinesterase (AChE) in a brain slice with single-cell resolution. The relative standard deviation from 25 cellular regions reached 73.3% exhibiting the difference of enzyme activity in the brain slice. Therefore, this approach utilizing the well-established kits provides an alternative single-cell-resolved strategy for the elucidation of enzymatic heterogeneity at the tissue level. [ABSTRACT FROM AUTHOR]

Three new ruthenium(II) complexes containing an N-heterocyclic carbene (NHC) ligand (RuNHC) have been successfully synthesized and proved to be efficient near-infrared (NIR) ECL (electrogenerated chemiluminescence) luminophores. In addition to the advantages of the lower-charge main motif (+1), the much lower oxidation potentials, and the longer metal to ligand charge transfer (MLCT) absorption bands, most importantly, these RuNHC complexes show higher, or at least comparable, ECL efficiency compared with Ru(bpy)32+ under the same experimental conditions; this demonstrates their great potential for applications in the NIR ECL imaging field in the future. [ABSTRACT FROM AUTHOR]

Potassium-selective polymer dots (K-Pdots) containing potassium ionophores were for the first time used for photoelectrochemical (PEC) analysis and yielded sensitive and specific detection of potassium ions. The successful PEC analysis using ion-selective Pdots underscored the effectiveness of the strategy deployed and suggested the potential universality of this strategy for the detection of metal ions, which should advance the development of PEC sensors in ion analysis. [ABSTRACT FROM AUTHOR]

Upconverting ion-selective nanoparticles that emit light at the near-infrared region are prepared here. The transport of calcium ions induces the deprotonation of the incorporated chromoionophore (P6) through ion exchange resulting in an increase in the emission of UCNPs for the detection of intracellular calcium ions. [ABSTRACT FROM AUTHOR]

We report a GNR-assisted NIR-activated tool that could open TRPV1 ion channels and regulate apoptotic protein expression, thereby inducing cell apoptosis, which might be an effective approach for cancer therapy. [ABSTRACT FROM AUTHOR]

We developed an electrochemiluminescence (ECL) microscopy technique to image the structure-dependent electrocatalytic reactivity of bimetallic Pd–Au nanorods (NRs) at the single-particle level. [ABSTRACT FROM AUTHOR]

Based on the structural programmability and spatial addressability of DNA nanodevices, a target-triggered, enzyme-free 3D DNA walker, comprising of hairpin DNA assembled gold nanoparticles with a local catalytic hairpin assembly reaction, was developed for the highly sensitive detection of intracellular tumor-associated microRNAs. [ABSTRACT FROM AUTHOR]

A target-triggered, self-powered strategy for in situ monitoring of intracellular microRNAs was fabricated via a versatile DNAzyme–MnO2 nanosystem, which integrates delivery, quenching, target recognition, self-supply of cofactors and signal amplification all in one. [ABSTRACT FROM AUTHOR]

Ratiometric electrochemiluminescence (ECL) assays have been widely applied in biosensing because of eliminated outside interferences and improved reliability in detection. In order to construct ratiometric ECL biosensors with high sensitivity and reliability, it is critical to find two signal emitters with suitable applied potentials or emission wavelengths. This review aims to discuss recent advances and trends of ratiometric ECL biosensors in terms of ECL materials and corresponding ratiometric sensing approaches. We focus on four types of ratiometric ECL biosensors based on particular ECL materials and ratiometric sensing strategies. [ABSTRACT FROM AUTHOR]

We demonstrate an approach using a plasmon-accelerated electrochemical reaction to improve the performance of scanning electrochemical microscopy. [ABSTRACT FROM AUTHOR]

We report a facile approach to fabricate a gold nanocone electrode for monitoring dopamine release from individual vesicles. [ABSTRACT FROM AUTHOR]

The molecular profiling of single axons and dendrites in living neurons could provide important information for the better understanding of neuron function. Here, electrosyringe-assisted electrospray mass spectrometry (MS) is established for the first time to achieve intracellular sampling from one axon or dendrite in living neurons for mass spectrometric analysis. The key is the insertion of a ∼130 nm capillary tip into one axon or dendrite to load the cytosol through electro-osmotic flow. The ionization efficiency from the nano-capillary is enhanced to guarantee mass spectrometric analysis of multiple components from the axon and dendrite. Higher levels of pyroglutamic acid and glutamic acid are revealed in the axon compared to in the body and dendrite. This uneven distribution is in accordance with the accumulation of neurotransmitters in the axon for information delivery. The achievement of electrosyringe-assisted electrospray MS is to unveil the molecular distribution in the whole living neuron, which offers the feasibility to deeply investigate molecular communication between the axon/dendrite and the body inside neurons. [ABSTRACT FROM AUTHOR]

Herein, we present a rapid, efficient and regioselective phosphorylation method at the 5′-position of unprotected ribose and ribonucleosides with pyrophosphate in the gas phase, which involves the formation of anionic complexes via electrospray ionization and collisional activation to induce phosphorylation within the complexes. [ABSTRACT FROM AUTHOR]

Proximity induced intramolecular nucleotide strand displacement, which can be simply performed in a single tube or in a complex cellular environment, is one of the key mechanisms for the detection of biological targets, especially for significant genetic molecules. The host factor for RNA phage Qb replication (Hfq), with two distinct single stranded RNA binding sites, has excellent properties as an affinity ligand in a proximity induced reaction. In this research, a versatile RNA chaperone-Hfq assisted RNA annealing strategy for the sensitive detection of the intermediate product, oligouridylated RNA, in a genetic regulation process was developed. Benefiting from the high binding affinity of Hfq for the probe and the target, the sensitive determination of oligouridylated RNA in cell lysis and human cervical cancer (HeLa) cells was successfully achieved. This study has also revealed that the Hfq assisted RNA annealing strategy can be further extended and applied in specific microRNA analysis, and RNA related tumorigenicity and disease diagnosis. [ABSTRACT FROM AUTHOR]

Modern optical detection technology plays a critical role in current clinical detection due to its high sensitivity and accuracy. However, higher requirements such as extremely high detection sensitivity have been put forward due to the clinical needs for the early finding and diagnosing of malignant tumors which are significant for tumor therapy. The technology of isothermal amplification with nucleic acids opens up avenues for meeting this requirement. Recent reports have shown that a nucleic acid amplification-assisted modern optical sensing interface has achieved satisfactory sensitivity and accuracy, high speed and specificity. Compared with isothermal amplification technology designed to work completely in a solution system, solid biosensing interfaces demonstrated better performances in stability and sensitivity due to their ease of separation from the reaction mixture and the better signal transduction on these optical nano-biosensing interfaces. Also the flexibility and designability during the construction of these nano-biosensing interfaces provided a promising research topic for the ultrasensitive detection of cancer diseases. In this review, we describe the construction of the burgeoning number of optical nano-biosensing interfaces assisted by a nucleic acid amplification strategy, and provide insightful views on: (1) approaches to the smart fabrication of an optical nano-biosensing interface, (2) biosensing mechanisms via the nucleic acid amplification method, (3) the newest strategies and future perspectives. [ABSTRACT FROM AUTHOR]

A multifunctional Ag NP based nanocomposite was fabricated which realized accurate targeting of specific cancer cells and completely initiative therapy without any photoexcitation. [ABSTRACT FROM AUTHOR]

Plasmon rulers (PRs) exploit the potential of plasmon coupling between individual pairs of noble metal nanoparticles in biological processes, especially single-molecule detection. Herein, for the first time, we report a strategy based on Ag PRs for in situ monitoring of the extension process of telomerase primer (TSP) activated by a single telomerase. [ABSTRACT FROM AUTHOR]

In this paper, we propose a generalized concept of microfluidic polydimethylsiloxane (PDMS) on paper (POP) devices, which combines well the merits of paper chips and PDMS chips. First, we optimized the conditions for accurate PDMS spatial patterning on paper, based on screen printing and a high temperature enabled superfast curing technique, which enables PDMS patterning to an accuracy of tens of microns in less than ten seconds. This, in turn, makes it available for seamless, reversible and reliable integration of the resulting paper layer with other PDMS channel structures. The integrated POP devices allow for both porous paper and smooth channels to be spatially defined on the devices, greatly extending the flexibility for designers to be able to construct powerful functional structures. To demonstrate the versatility of this design, a prototype POP device for the colorimetric analysis of liver function markers, serum protein, alkaline phosphatase (ALP) and aspartate aminotransferase (AST), was constructed. On this POP device, quantitative sample loading, mixing and multiplex analysis have all been realized. [ABSTRACT FROM AUTHOR]