Rapid Signal Response Research Articles

Time-reversal symmetry breaking in the chemosensory array reveals a general mechanism for dissipation-enhanced cooperative sensing

The Escherichia coli chemoreceptors form an extensive array that achieves cooperative and adaptive sensing of extracellular signals. The receptors control the activity of histidine kinase CheA, which drives a nonequilibrium phosphorylation-dephosphorylation reaction cycle for response regulator CheY. Cooperativity and dissipation are both important aspects of chemotaxis signaling, yet their consequences have only been studied separately. Recent single-cell FRET measurements revealed that kinase activity of the array spontaneously switches between active and inactive states, with asymmetric switching times that signify time-reversal symmetry breaking in the underlying dynamics. Here, we present a nonequilibrium lattice model of the chemosensory array, which demonstrates that the observed asymmetric switching dynamics can only be explained by an interplay between the dissipative reactions within individual core units and the cooperative coupling between neighboring units. Microscopically, the switching time asymmetry originates from irreversible transition paths. The model shows that strong dissipation enables sensitive and rapid signaling response by relieving the speed-sensitivity trade-off, which can be tested by future single-cell experiments. Overall, our model provides a general framework for studying biological complexes composed of coupled subunits that are individually driven by dissipative cycles and the rich nonequilibrium physics within.

A signal-amplified electrochemical immunosensor for the detection of sulfadimidine in crayfish using COOH-MWCNTs-Fe3O4-GO nanohybrids modified working electrode

The label-free immunosensing technique is highly valued for its sensitivity and specificity, and advantages of simple preparation, fast detection (one-step), and rapid signal response. However, the sensitivity, stability, and specificity of this technique not only depend on the performance of antibodies, but also on the immunosensing interface of the bare glassy carbon electrode (GCE). This includes factors such as electrical conductivity, biocompatibility, and antibody loading capacity. In this study, carboxyl multiwalled carbon nanotubes-ferrosoferric oxide-graphene oxide (COOH-MWCNTs-Fe3O4-GO) was screened as the modified material of GCE to create an ideal immunosensing interface for the biological reaction between antibody-sulfadimidine (anti-SM2) and SM2. The structure of both nanomaterials and the immunosensor were characterized. The nanohybrid exhibited a uniform interwoven structure of laminar and tubular components. This unique structure allows for a higher capacity for antibody loading. Based on this, a novel electrochemical immunosensor was constructed using COOH-MWCNTs-Fe3O4-GO/GCE, which exhibited a high anti-SM2 loading capacity and a rapid detection time of 30 min. The immunosensor exhibited a linear detection range of 0.01–100 ng/mL for SM2, with a limit of detection (LOD) of 0.003 ng/mL and a limit of quantification (LOQ) of 0.01 ng/mL. Additionally, satisfactory recoveries ranging from 94.40% to 109.00% were achieved in crayfish samples, with a relative standard deviation (RSD) of 4.97–8.64%. A novel immunosensors for highly sensitive detection of SM2 has been developed, which may provide an alternative idea for determination of SM2 in crayfish and other seafood.

Fabrication of ternary hybrid composites of Co-MOFs/MoS2/PEDOTs for sensitive detection of dopamine and norepinephrine in biological samples

In this study, a simple and multifunctional application for Co-based organic frameworks (Co-MOFs) with molybdenum disulfide (MoS2) and poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate (PEDOTs:PSS) is presented. The Co-MOFs with MoS2 exhibit excellent peroxidase mimicking and catalytic activities, making them suitable for colorimetric dopamine sensors. From an electrochemical standpoint, fouling-free and selective sensing of dopamine (DA) and norepinephrine (NE) is highly challenging. However, the synergistic effect of morphological tunability of Co-MOFs with hybrid composites of MoS2 and PEDOTs:PSS offers a wide detection concentration range of 2 nM-350 µM for DA and 20 nM-1000 µM for NE, high sensitivity, excellent anti-fouling, facile kinetic rate reaction, and rapid signal response. A high selectivity rate was achieved in the presence of twenty times higher concentrations of a mixture of ascorbic acid, uric acid, and other bio-chemical co-interferents. Interestingly, ultrasensitive detection limits of 0.23 nM and 2.18 nM (S/N = 3) were achieved for DA and NE, enabling the real-time precise detection of cellular concentrations in PC12 living cells, and biological fluid samples with simple dilution pretreatments. Moreover, the sensor demonstrated satisfactory reproducibility and stability. Finally, the morphological and composite activity-based probes can detect neurotransmitter concentrations in real samples beyond the concentration limit, suggesting a potential clinical sensor tool.

Probe-impregnated monolithic polymer as a robust solid-state colorimetric chemosensor for selective sensing of Hg2+ in environmental water and cigarette samples

The current study developed a novel aqua-compatible and naked-eye portable solid-state opto-sensor for selective and sensitive detection of ultra-trace Hg2+ ions. The developed chemosensor was fabricated by the direct impregnation of a chromoionophoric probe composed of 2,3-bis((4-isopropylbenzylidene)amino)maleonitrile (PDPM) onto the surface of structurally tailored porous polymer monolithic framework. The template exhibited a highly porous network with greater surface area, which led to the effective anchoring of probe molecules onto the surface of the polymer template, thus serving as an efficient platform to constitute a regenerative solid-state chemosensor. The sensor rendered a superior color shift from dull white to dijon yellow after complexing with Hg2+. The surface, structural, and morphological aspects of the sensor were evaluated using FE-SEM, HR-TEM, EDAX, SAED, p-XRD, N2 adsorption isotherm, and XPS. Rigorous optimization of the effects of different analytical parameters on the sensing performance of the PDPM sensor material was ensured. The monolithic sensor had an optimum sensing performance at pH 8.0, rapid signal response kinetics of 60s and a broad linear response range of 0.5–150.0 μg/L with a 0.22 μg/L detection limit. Furthermore, the sensor was also tolerant of foreign matrix constituents, thereby enabling it to be highly selective in detecting Hg2+. Sensor recovery was analyzed to be possible via Hg2+ desorption using 0.01 M EDTA without compromising its sensing performance. It had reutilization potential for up to eight regenerative cycles with excellent data reliability (recovery ≥99.4% and RSD ≤1.4%). The practicability of the fabricated sensor was investigated using various water and cigarette samples. Experimental data revealed that the developed chromoionophoric sensor was reusable, eco-friendly, low-cost, and possessed superior sensing capabilities, making it more feasible for on-site analysis of environmental samples. The designed sensor has the potential for further investigations and applications as a sensor kit for facilitating heavy metal detection in remote places.

Research on Electric Control Brake System Based on Railway Vehicle

The trackless train may be mixed with other vehicles in the city. Therefore, developing a vehicle braking system with high reliability, fast response, and powerful braking force is necessary. In this research, the chip module control is added to each control part to realize rapid electric signal collection and response, and then the pneumatic control of each actuator is used to realize rapid and flexible electric braking control of the vehicle. The braking system has been tested on the test bench in the factory, and its response speed and braking effect have increased by 10% compared with the traditional bus braking system. When the performance test is carried out on the real vehicle, the braking effect is also improved by nearly 10%. Through the design of the braking system, the braking system of domestic trackless trains can be perfectly solved.

A red fluorescent small-molecule for visualization of higher-order cyclic dimeric guanosine monophosphate (c-di-GMP) structure in live bacterial cells and real-time monitoring of biofilm formation on biotic and abiotic surfaces

Cyclic dimeric guanosine monophosphate (c-di-GMP) is an important second messenger in bacteria. It regulates a wide range of bacterial functions and behaviors including biofilm formation that causes chronic infections and antibiotic resistance. C-di-GMP being as a signal transducer in bacteria is known to exist in monomer and dimer form. Recent studies also discover that c-di-GMP can form higher-order oligomers, such as tetramer and octamer, which may have physiological roles in bacterial cells. Moreover, the tetrameric c-di-GMP structure was reported to link two subunits of a transcription factor (BldD), which controls the progression of multicellular differentiation in sporulating actinomycete bacteria and then mediates the dimerization process. Current understanding on higher-order oligomers of c-di-GMP is relatively limited compared to its monomer or dimer structure. To probe and visualize the higher-order structure of c-di-GMP and its associated biofunctions in live bacterial cells with fluorescence techniques for mechanistic study and cellular investigation is important. Nonetheless, the sensitive and selective fluorescent probe with a rapid signal response for higher-order oligomers of c-di-GMP is currently lacking. In the present study, a series of fluorescent probes that preferentially interacted with tetrameric c-di-GMP and generated red fluorescence signal promptly were synthesized and investigated. The interaction mechanism was studied with 1H NMR and molecular docking. In addition, the ligand was demonstrated as an excellent molecular fluorescent probe for bioimaging of tetrameric c-di-GMP structure and monitoring of biofilm formation on both biotic and abiotic surfaces with pathogenic bacteria including Pseudomonas aeruginosa PAO1 and Bacillus subtilis 168.

Highly conductive organic-ionogels with excellent hydrophobicity and flame resistance

Very different from electronic conductors, ionic conductors usually possess some unique functions such as stretchability, transparency and ionic conductivity, thus exhibiting a great promise in the flexible wearable electronic devices. Herein, we develop a novel stretchable transparent organic-ionogel (OIG-TBP-50) via a rapid photo-curing process, in which we select the mixture of tributyl phosphate (TBP) and 1-butyl-2,3-dimethylimidazolium bis(trifluoromethylsulfonyl)amine ([BMMIm][NTf2]) as fireproof and conductive solvent, respectively. Just benefiting from the good synergistic effect of TBP and [BMMIm][NTf2], our-designed OIGs demonstrate excellent hydrophobicity and flame resistance as well as perfect stretchability (757%), high transparency (93%) in visible region, good environmental stability, wide temperature tolerance range (from −55 °C to 180 °C) and high ionic conductivity (1.73 × 10-3 S cm−1 at room temperature). In addition, our stretchable transparent OIGs even could light LED lamps under an alternating current field when directly used as the flexible conductive substrate. Further applying such OIGs as ionic conductor to assemble flexible sensor and touch screen, both of them could transport rapid signal response under slight touch stress.

Colorimetric optical nanosensors for trace explosive detection using metal nanoparticles: advances, pitfalls, and future perspective

Warfare threats and acts of terror are challenging situations encountered by defense agencies across the globe and are of growing concern to the general public, and security-minded policy makers. Detecting ultra-low quantities of explosive compounds in remote locations or under harsh conditions for anti-terror purposes as well as the environmental monitoring of residual or discarded explosives in soil, remains a major challenge. The use of metal nanoparticles (NPs) for trace explosive detection has drawn considerable interest in recent years. For nano-based explosive sensor devices to meet real-life operational demands, analytical parameters such as, long-shelf life, stability under harsh conditions, ease-of-use, high sensitivity, excellent selectivity, and rapid signal response must be met. Generally, the analytical performance of colorimetric-based nanosensor systems is strongly dependent on the surface properties of the nanomaterial used in the colorimetric assay. The size and shape properties of metal NPs, surface functionalisation efficiency, and assay fabrication methods, are factors that influence the efficacy of colorimetric explosive nanosensor systems. This review reports on the design and analytical performances of colorimetric explosive sensor systems using metal NPs as optical signal transducers. The challenges of trace explosive detection, advances in metal NP colorimetric explosive design, limitations of each methods, and possible strategies to mitigate the problems are discussed.

A NEW METHOD FOR ACCURATE PREDICTION OF SPERMATOGENESIS: FSH/T AND T IN SEMINAL PLASMA

A NEW METHOD FOR ACCURATE PREDICTION OF SPERMATOGENESIS: FSH/T AND T IN SEMINAL PLASMA

Porous silica and polymer monolith architectures as solid-state optical chemosensors for Hg2+ ions

We demonstrate a simple strategy to concoct a competent solid-state opto-chemosensor for the selective and sensitive visual detection of Hg2+ ions. The sensor fabrication involves the utilization of indigenously prepared mesoporous silica and polymer monoliths as probe anchoring templates and 8-hydroxy-7-(4-n-butylphenylazo) quinoline (HBPQ) as the chromo-ionophoric probe for Hg2+ sensing. Both the monoliths are designed with discrete structural and morphological features to serve as efficient host templates. The structural and surface features of the monoliths are characterized using p-XRD, TEM, SEM, SAED, EDAX, XPS, and N2 isotherm analysis. The synergetic features of monolith structural hierarchy along with the probe's selective chelating ability enable rapid signal response and remarkable ion selectivity for Hg2+. The solid-state sensors evince a linear signal response from 0.6 to 150μg/L for Hg2+ recognition, with superior data authenticity and replication that is preceded by an RSD value of ≤ 2.25% when tested with real water samples.Graphical abstract Mesoporous silica and polymer monolith architects hosting HBPQ probe molecules demonstrate an excellent visual sensing of ultra-trace (μg/L) Hg2+ in various water samples with a striking color transition from light orange to dark red upon complexation of probe with Hg2+. The solid-state sensors are Hg2+ ion selective, super-responsive, real-time applicable, and also reusable.

Gamma Visual Stimulation Induces a Neuroimmune Signaling Profile Distinct from Acute Neuroinflammation.

Many neurodegenerative and neurological diseases are rooted in dysfunction of the neuroimmune system; therefore, manipulating this system has strong therapeutic potential. Prior work has shown that exposing mice to flickering lights at 40 Hz drives gamma frequency (∼40 Hz) neural activity and recruits microglia, the primary immune cells of the brain, revealing a novel method to manipulate the neuroimmune system. However, the biochemical signaling mechanisms between 40 Hz neural activity and immune recruitment remain unknown. Here, we exposed wild-type male mice to 5-60 min of 40 Hz or control flicker and assessed cytokine and phosphoprotein networks known to play a role in immune function. We found that 40 Hz flicker leads to increases in the expression of cytokines which promote microglial phagocytic states, such as IL-6 and IL-4, and increased expression of microglial chemokines, such as macrophage-colony-stimulating factor and monokine induced by interferon-γ. Interestingly, cytokine effects differed as a function of stimulation frequency, revealing a range of neuroimmune effects of stimulation. To identify possible mechanisms underlying cytokine expression, we quantified the effect of the flicker on intracellular signaling pathways known to regulate cytokine levels. We found that a 40 Hz flicker upregulates phospho-signaling within the nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) and mitogen-activated protein kinase (MAPK) pathways. While cytokine expression increased after 1 h of 40 Hz flicker stimulation, protein phosphorylation in the NF-κB pathway was upregulated within minutes. Importantly, the cytokine expression profile induced by 40 Hz flicker was different from cytokine changes in response to acute neuroinflammation induced by lipopolysaccharides. These results are the first, to our knowledge, to show how visual stimulation rapidly induces critical neuroimmune signaling in healthy animals.SIGNIFICANCE STATEMENT Prior work has shown that exposing mice to lights flickering at 40 Hz induces neural spiking activity at 40 Hz (within the gamma frequency) and recruits microglia, the primary immune cells of the brain. However, the immediate effect of 40 Hz flicker on neuroimmune biochemical signaling was unknown. We found that 40 Hz flicker leads to significant increases in the expression of cytokines, key immune signals known to recruit microglia. Furthermore, we found that 40 Hz flicker rapidly changes the phosphorylation of proteins in the NF-κB and MAPK pathways, both known to regulate cytokine expression. Our findings are the first to delineate a specific rapid immune signaling response following 40 Hz visual stimulation, highlighting both the unique nature and therapeutic potential of this treatment.

MnII-Doped Cesium Lead Chloride Perovskite Nanocrystals: Demonstration of Oxygen Sensing Capability Based on Luminescent Dopants and Host-Dopant Energy Transfer.

The design of photoluminescence-quenching probes for molecular oxygen (O2) is always a large space to explore. Luminescent semiconductor nanocrystals (NCs) have been proposed as emerging oxygen-responsive probes, but the inherent O2 sensing of phosphorescent semiconductor NCs has not been reported so far. Here, we demonstrate the O2 sensing capability of MnII-doped CsPbCl3 nanocrystals (Mn:CsPbCl3 NCs) and reveal the role of O2 on the optical de-excitation process of such perovskite nanocrystals (PNCs). By adjusting the amount and distribution of MnII dopants, as well as the host-dopant energy transfer process in PNCs, we highlight that O2 can reversibly quench the MnII emission due to the temporary disturbance to the ligand field of near-surface MnII dopants in PNCs. In phosphorescence mode, the photoluminescence intensity of the Mn:CsPbCl3 NCs is quenched by 53% on increasing O2 concentration from 0 to 100%. The Stern-Volmer plot shows a good linear in the 0-12% O2 concentration range. High sensing reversibility and rapid signal response are also achieved. In our perception, the mechanism study makes our PNCs candidates for the optical probes of O2, and it is enlightening to explore more possibilities of the inherent O2 sensing based on the semiconductor-doped NCs (not restricted to MnII-doped PNCs) with phosphorescence emission.

Dynamic seesaw model for rapid signaling responses in eukaryotic chemotaxis

Directed movement of eukaryotic cells toward spatiotemporally varied chemotactic stimuli enables rapid intracellular signaling responses. While macroscopic cellular manifestation is shaped by balancing external stimuli strength with finite internal delays, the organizing principles of the underlying molecular mechanisms remain to be clarified. Here, we developed a novel modeling framework based on a simple seesaw mechanism to elucidate how cells repeatedly reverse polarity. As a key feature of the modeling, the bottom module of bidirectional molecular transport is successively controlled by three upstream modules of signal reception, initial signal processing, and Rho GTPase regulation. Our simulations indicated that an isotropic cell is polarized in response to a graded input signal. By applying a reversal gradient to a chemoattractant signal, lamellipod-specific molecules (i.e. PIP3 and PI3K) disappear, first from the cell front, and then they redistribute at the opposite side, whereas functional molecules at the rear of the cell (i.e. PIP2 and PTEN) act oppositely. In particular, the model cell exhibits a seesaw-like spatiotemporal pattern for the establishment of front and rear and interconversion, consistent with those related experimental observations. Increasing the switching frequency of the chemotactic gradient causes the cell to stay in a trapped state, further supporting the proposed dynamics of eukaryotic chemotaxis with the underlying cytoskeletal remodeling.

Tyrosine nitration of cytosolic peroxidase is probably triggered as a long distance signaling response in sunflower seedling cotyledons subjected to salt stress.

Present work focuses on tissue and concentration-dependent effect of nitric oxide (NO) on the modulation of cytosolic peroxidase (POD; EC 1.11.1.7) activity in 2-day old etiolated sunflower (Helianthus annuus L.) seedlings. Exogenously supplied NO (in the form of sodium nitroprusside [SNP] or diethylenetriamine NONOate [DETA]; 125 to 500 μM) results in noteworthy enhancement in seedling growth in a concentration dependent manner irrespective of salt-stress and differentially affects POD activity in 2-day old seedling cotyledons. Elevated NO availability leads to an increase in the specific activity of POD in a concentration-dependent manner within 48 hrs as a rapid signaling response. Purification of POD protein using immunoprecipitation technique has shown that cotyledons derived from salt stressed seedlings exhibit a higher extent of tyrosine nitration of POD as compared to the control seedlings. Out of the four tyrosine residues found in the amino acid sequence of POD, the one at position 100 has been predicted to undergo nitration. Thus, a probable NO-POD crosstalk is evident in sunflower seedling cotyledons accompanying salt stress.

Advances in Nanowire Transistor‐Based Biosensors

AbstractSemiconducting nanowires (NWs) present new opportunities for developing electrical biosensors due to their inherent properties, including large surface‐to‐volume ratio, rapid signal response, configurability in electronic devices, and nanoscale footprint comparable to biomolecular and subcellular structures. Field‐effect transistors (FETs) based on silicon nanowires (SiNWs) have proven to be a powerful and versatile tool in the biomedical fields. Recent advances in SiNW‐FET biosensors, including fundamental aspects and working principles, preparation of nanowires, and surface functionalization, as well as applications in biological analysis and cellular investigation, are discussed here. It is envisioned that nano‐FET devices will have several applications in fields such as clinical diagnosis, point‐of‐care testing, and screening for early disease.

Sensitive Detection of a Nerve-Agent Simulant through Retightening Internanofiber Binding for Fluorescence Enhancement.

In this work, we develop fluorescent hierarchical nanofiber bundles 1, which involve the internanofiber hydrogen-bonding interactions, for rapid and sensitive detection of diethyl chlorophosphate (DCP) vapor. First, the internanofiber hydrogen-bonding strength can be weakened by photoexcitation, which thereby increases the internanofiber spacing and decreases the fluorescence intensity. Then, when exposed to trace DCP vapor, the strong interactions between DCP and hydroxyl groups on the nanofibers can effectively retighten the nanofibers and enhance the fluorescence as the detection signal. In contrast, the interferences, such as common organic solvents, cannot retighten nanofiber bundles 1 because of the lack of strong interactions with the nanofibers. On the basis of this novel detection mechanism, fluorescence detection of DCP with rapid signal response (ca. 3 s) and high sensitivity (15 ppb) is achieved.

Ratiometric fluorescence probe for hydrazine vapor detection and biological imaging.

Hydrazine (N2H4) has been widely applied in most of the chemical industry; however, it is now believed that it can cause serious damage to protein and nucleic acid upon ingestion. Herein we introduced a specially designed molecular probe 1, with an electron deficient lactone group as a specially designed reactive site and a naphthalimide fluorophore that is easily modified owing to lactone involvement. The free probe 1 exhibited blue fluorescence in neutral buffer owing to the low favorability of ICT (intramolecular charge transfer), while the specially designed lactone group could potentially undergo a ring-opening reaction with hydrazine, resulting in a favoured ICT effect and bathochromically shifted (125 nm) fluorescence response. The ratiometric fluorescence signal enabled quantitative determination of hydrazine using probe 1 in complex applications. Besides, probe 1 features a rapid signal response time (within 5 min) and low detection limit (36 nM) for hydrazine. Utilizing these excellent properties, probe 1 was further applied in hydrazine vapor detection and bio-imaging. Conceptually, we now present a new approach for the detection of hydrazine, and the enhanced performances of probe 1 will promote its applications in living systems and the environment.

“Turn-on” fluorescent probe detection of Ca2 + ions and applications to bioimaging

Ca2+ is intracellular divalent cation with the largest concentration variations and involved in many biological phenomena and often acted as a second messenger in signaling pathway. Therefore, the development of probes for specific Ca2+ detection is of great importance. Herein, a novel turn-on fluorescent probe for the detection of Ca2+ in MeCN-aqueous medium was designed and synthesized. The probe displayed responses to Ca2+ with a fluorescence enhancement at 525nm, accompanying with a distinct fluorescence change from nearly colorless to bright yellow-green. Besides, the probe exhibited a rapid signal response time (within 25s), a good linearity range and a lower detection limit (2.70×10−7M). In addition, the ability of the probe to detect Ca2+ in living cells (HeLa cells) via an enhancement of the fluorescence has also been demonstrated.

Importance of Estrogenic Signaling and Its Mediated Receptors in Prostate Cancer.

Prostate cancer (PCa) treatment was first established by Huggins and Hodges in 1941, primarily described as androgen deprivation via interference of testicular androgen production. The disease remains incurable with relapse of hormone-refractory cancer after treatments. Epidemiological and clinical studies disclosed the importance of estrogens in PCa. Discovery of estrogen receptor ERβ prompted direct estrogenic actions, in conjunction with ERα, on PCa cells. Mechanistically, ERs upon ligand binding transactivate target genes at consensus genomic sites via interactions with various transcriptional co-regulators to mold estrogenic signaling. With animal models, Noble revealed estrogen dependencies of PCa, providing insight into potential uses of antiestrogens in the treatment. Subsequently, various clinical trials were conducted and molecular and functional consequences of antiestrogen treatment in PCa were delineated. Besides, estrogens can also trigger rapid non-genomic signaling responses initiated at the plasma membrane, at least partially via an orphan G-protein-coupled receptor GPR30. Activation of GPR30 significantly inhibited in vitro and in vivo PCa cell growth and the underlying mechanism was elucidated. Currently, molecular networks of estrogenic and antiestrogenic signaling via ERα, ERβ and GPR30 in PCa have not been fully deciphered. This crucial information could be beneficial to further developments of effective estrogen- and antiestrogen-based therapy for PCa patients.

A rapid and highly sensitive fluorescent imaging materials for thiophenols

Thiophenols, a class of toxic and polluting compounds, are widely used in industrial production. Meanwhile, some aliphatic thiols play important roles in living organisms. Therefore, the development of probes for specific thiophenol detection is of great importance. Herein, a novel highly sensitive and selective ‘off-on’ fluorescent probe for detecting thiophenols has been developed by an ICT mechanism through a rational design. The probe displays a large Stokes shift (140 nm) and 60-fold fluorescence intensity enhancement. More importantly, the probe features a rapid signal response time (within 100 s), a good linearity range and the detection limit is as low as 13 nM. In addition, the ability of the probe to detect thiophenols in living cells (HepG2 cells) via an enhancement of the fluorescence has also been demonstrated.