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Abnormal increases in glucagon (GCG) are the primary cause of type II diabetes mellitus. When GCG interacts with a glucagon receptor (GCGR), GCG can increase the blood glucose level. In this paper, a compound that could interfere with the binding of GCG and GCGR to inhibit the increase of blood glucose was investigated. First, molecular docking was used to conduct preliminary screening of compounds whose active components could combine with GCGR by AutoDock Vina. The binding of the receptor-ligand complex was analyzed by PyMOL. Results showed that dauricine could tightly bind to the receptor pocket. Second, the plasmid pcDNA3.1(+)-GCGR containing the target gene was transfected into HEK293 cells for expression, which was the cell model established to screen GCGR antagonist. Dauricine, the lead compound of glucagon receptor antagonist (GRA), was screened using the GRA screening model in vitro. Finally, using [Des-His1, Glu9]-Glucagon amide as the positive control, flow cytometry was used to express the antagonistic effect of the compound. Consequently, dauricine can antagonize the GCGR.

In this paper, highly fluorescent carbon dots were synthesized from sodium ascorbate and polyethyleneimine at room temperature (R-CDs). The proposed green synthesis method was energy-saving, environmentally friendly and easy online. R-CDs exhibit an optimal emission peak of 490 nm under excitation at 380 nm with a quantum yield of 32 %. R-CDs morphology, composition, and properties were characterized using TEM, FTIR, XPS, UV-vis and fluorescence spectroscopy. The study revealed that nitrite quenched the fluorescence of R-CDs under acidic conditions. Subsequently, this discovered reaction of R-CDs and nitrite was combined with flow-injection technology, and a simple, precise and automatic fluorescence strategy for nitrite determination was accomplished. The response to nitrite was linear in 5-300 μg·L

Total antioxidant capacity (TAC) is an important indicator for evaluating oxidative stress of the human body. Since TAC is related to the concentration of reducing substances, it can be detected by using peroxidase-like or oxidase-like activity of nanozyme materials. In this work, the cobalt and nitrogen co-doped carbon dots (Co/N-CDs) are fabricated for building stability and high peroxidase-like nanozyme through the Box-Behnken design of response surface methodology. The morphology and luminescence properties of obtained Co/N-CDs were characterized by TEM and fluorophotometer, respectively. Interestingly, the surface charge of Co/N-CDs are innovatively investigated by a simple and widespread gel electrophoresis, which holds the potential to be an alternative to Zeta potential analysis. In addition, a flow injection spectrophotometric assay to detect ascorbic acid is develop with a high sensitivity and automation based on a Co/N-CDs/guaiacol/H

This work developed a sensitive electrochemiluminescence (ECL) biosensor based on a cyclometalated iridium(III) complex ((bt)2Irbza), which was synthesized for the first time. Annihilation, reductive-oxidative, and oxidative-reductive ECL behaviors of (bt)2Irbza were investigated, respectively. The oxidative-reductive ECL intensity was the strongest compared with the other two, which showed 16.7 times relative ECL efficiency compared with commercial [Ru(bpy)3]2+ under the same experimental conditions. Therefore, an ECL biosensing system with (bt)2Irbza as the anodic luminophore was established for miRNA detection based on a closed bipolar electrode (BPE). Combined with both steric hindrance and catalytic effects induced by hemin/G-quadruplex in the cathodic reservoir of BPE that changed the Faraday current of the cathode and thus mediated the ECL intensity of (bt)2Irbza in the anode of BPE, the ECL sensor stated an ultrahigh sensitivity for microRNA (miRNA-122) analysis with a detection limit of 82 aM.

An indene-chalcone-based fluorescence probe 1 was synthesized and characterized. Under physiological conditions (containing 5% DMSO), probe 1 showed satisfactory stability with a low background signal and recognized carboxylesterases (CEs) based on the catalytic hydrolysis of ester groups, releasing a significant green fluorescence. Probe 1 presents several features including a short response time (within 20 min), low detection limit (1.3 × 10

A fluorescence-enhanced and lysosome-targeted Al3+ probe (1) based on a pyrazole-containing hydrazone was developed in this work. The fluorescent probe 1 displays an OFF–ON fluorescence response to Al3+ in the lysosome pH environment. In addition, the resultant 1–Al3+ complex could act as an ON–OFF fluorescence sensor for F−. Fluorescence imaging shows that 1 is suitable for visualization of Al3+ in lysosomes of HeLa cells.

Phosgene (carbonyl chloride, COCl

CRISPR-Cas12a system exhibits tremendous potential in accurate recognition and quantitation of nucleic acids and non-nucleic-acid targets thanks to the discovery of its cleavage capability toward single-stranded DNA (ssDNA). In this study, we developed an efficient electrochemiluminescence (ECL) sensing platform based on CRISPR-Cas12a for the analysis of adenosine triphosphate (ATP). In the presence of the target, the successful release of the DNA activator is specially recognized by Cas12a-crRNA duplex and activates the cleavage of ferrocene (Fc) labeled–ssDNA (Fc-ssDNA) modified on the cathode of bipolar electrode (BPE), resulting in a decrease of ECL intensity of [Ru(bpy)3]2+/TPrA in the anodic cell of BPE. By means of the unique combination of Cas12a with ECL technique based on BPE, it can convert the recognition of target ATP into a detectable ECL signal. The detection limit of ATP was determined to be 0.48 nM under the optimal conditions. This work will expand the application of CRISPR-Cas detection system and propose a potential method for the analysis of non-nucleic-acid targets.

A lysosome-targeting ratiometric fluorescent probe was synthesized for detecting sulfite based on sulfite-triggered nucleophilic addition reaction. Due to the specific reaction, the fluorescence intensity ratio (I

Hydrogen sulfide (H

This paper describes a bidirectional electrochemiluminescence (ECL) biosensor for the detection of microRNA-141 (miRNA-141) with aM level detection limit and two-segment 8 orders of magnitude linear range. Hemin/G-quadruplex DNAzyme was assembled on carbon nitride nanosheets and Au nanoparticles modified electrode. The ECL of carbon nitride nanosheets could be enhanced by the right amount of H2O2 (no more than 10 mM) and then inhibited by excessive H2O2 when 0.1 M K2S2O8 acted as coreactant. In the presence of excessive H2O2 (20 mM), a recovery of ECL intensity was obtained due to the catalytic reduction of H2O2 caused by hemin/G-quadruplex DNAzyme at lower target concentrations, and then an ECL decrease occurred mainly by biocatalytic precipitation (BCP)-induced charge transfer resistance on the electrode surface at higher target concentrations. Therefore, based on the change of the ECL intensity caused by the catalytic reduction of H2O2 and BCP, a highly sensitive bidirectional miRNA sensor with ultralow detection limit of 7.9 aM and wide linear range from 10-17 to 10-9 M was obtained. This work could attract more attention on the study of multiple mechanisms and also provides a more sensitive and precise method for the analysis of nucleic acids.

A simple rhodamine-based fluorescent probe L1, which exhibits good response to Fe3+ in CH3CN/Tris-HCl buffer (v:v = 9:1, pH 7.00) solution. With the experimental conditions optimized, the probe L1 could be used as a fluorescent and colorimetric probe for Fe3+ with the detection limit as low as 0.29 μM. The binding constant (Ka) of Fe3+ binding to the probe L1 were calculated to be 1.4 × 1010 M−2, respectively from a Benesi-Hildebrand plot. With the addition of Fe3+, the CH3CN/Tris-HCl buffer (v:v = 9:1, pH 7.00) solution of the probe L1 exhibited a obviously color change from transparent to pink with distinctive changes. More importantly, the recognition process of the probe L1 for Fe3+ was chemically reversible on the addition AcO−.

A rhodamine hydrazone 1 bearing coumarin moiety was designed and prepared. Compound 1 exhibited high selectivity toward Co2+ and trivalent metal ions with fluorescence enhancement in CH3OH solution. However, 1 selectively responded to Al3+ in nearly pure H2O media and was further applied to monitor Al3+ in live cells. Moreover, 1 could also act as a colorimetric probe toward Cu2+ in either CH3OH or H2O solution. In addition, sensor 1 displayed aggregation-induced ratiometric emission (AIRE) activities in mixed H2O/CH3OH solution.

A simple asymmetric hydrazone 1 based on salicylaldehyde was designed and prepared, and exhibited an evident aggregation-induced emission (AIE) at a long wavelength of 570 nm in aqueous medium. Probe 1 can selectively sense Al3+ in CH3OH solution through the chelation-enhanced fluorescence mechanism and also recognize Cu2+ via fluorescence quenching in H2O solution through the Cu2+-induced assembly of aggregates. In addition, the probe can be applied for detecting Cu2+ in biological samples.

A novel rhodamine-based Schiff base derivative was obtained via the simple condensation of substituted formyl-1H-pyrrole and rhodamine 6G hydrazone. Fluorescence resonance energy transfer enabled the subsequent use of the derivative as a naked-eye colorimetric and ratiometric fluorescent sensor for Cu2+ in semi-aqueous solution, and the existence of the morpholine group enabled the further application of the sensor in imaging Cu2+ in the lysosomes of HeLa cells.

A ratiometric fluorescent probe for Pd2+ has been constructed through appending indole to rhodamine B. The response process of Pd2+ to probe was also verified by UV-vis, fluorescence, ESI-MS, 1H NMR and density functional theory calculation. Moreover, the highly sensitive and selective probe was successfully applied to monitor Pd2+ in living cells.

Hypochlorite plays a significant role in physiological processes, particularly regulation of lysosomal functions, and is involved in various diseases. Thus, it is crucial to develop highly sensitive and selective molecule tools to detect HClO in lysosomes. Herein, a novel 2H-benzo[h]chromene-pyridine derivative (1) was synthesized through condensation reaction, which exhibited a notable deep-red emission at 640 nm in pure water. This deep-red emission was specifically quenched by adding ClO−. The response of probe 1 toward ClO− was rapid (within 10 s), sensitive (detection limit of 0.012 μM), and effective over a wide range of pH (1.0–12.0). Due to the existence of morpholine as the lysosome-targeting unit, the probe was successfully utilized to monitor lysosomal ClO−. Moreover, the probe 1 was also applied to detecting ClO− in zebrafish.

The hydrazone sensor (1) derived from pyrazine-2-carbohydrazide and 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) was applied to the fluorescent “turn-on” detection of Al3+ in semi-aqueous solutions. The strongly emissive 1+Al3+ complex could identify F− among other tested anions. The detection limits of sensor 1 for Al3+ and F− were 0.18 and 0.20 μM, respectively, which are both much lower than the corresponding values recommended by the World Health Organization, namely, 7.41 and 79 μM. Several spectral methods, including single crystal X-ray analysis for the crystal structures of the Cu2+ and Ni2+ complexes of sensor 1, as well as the density-functional theory method, were used to elucidate the binding mode between the sensor and Al3+. 1 can also be used for a selective sensor to continuously monitor Al3+ and F− in living cells.

A simple hydrazone probe (1) was designed and synthesized for the successive detection of Al3+ and pyrophosphate (PPi) in almost 100% buffer environment. The probe provided O2N donor set for chelation with Al3+, leading to a distinct fluorescence boost at 510 nm. The in-situ formed 1-Al3+ complex detected PPi with an “on-off” behavior. The detection limits for Al3+ and PPi were 35.7 nM and 76 nM, respectively. Benefiting from the existence of morpholine as lysosome-targeting group, probe 1 was successfully applied to the detection of Al3+ and PPi in lysosomes.

A simple water soluble hydrazone sensor (1·Cl) has been developed to selectively chelate with Zn2+ via an O2N donor set, leading to specific fluorescence enhancements. The highly emissive 1-Zn2+ complex can serve as a reversible on-off sensor for S2−. The detection limits of 1·Cl for Zn2+ and S2− are 66.0 and 32.6 nM, respectively. The recognition mechanism was carefully investigated through FL, UV-vis, 1H NMR, ESI-MS, time-resolved fluorescence, and density functional theory (DFT) calculations. Owing to the mitochondria-targeting ability of the terminal quaternary ammonium moiety, 1·Cl was successfully applied to image mitochondrial Zn2+ and S2−.

A water-soluble salicylaldehyde-based thiosemicarbazone has been designed and applied to the selective fluorescent turn-off detection of Hg2+ ions. The probe-Hg2+ system acted as a turn-on probe toward biothiols, including cysteine, homocysteine, and glutathione. The limits of detection of the probe toward Hg2+, cysteine, homocysteine, and glutathione are 0.52 μM, 0.74 μM, 0.31 μM, and 0.27 μM, respectively. The mechanisms are carefully confirmed by fluorescence spectrometry, UV-visible spectrometry, electrospray ionization mass spectra, hydrogen nuclear magnetic resonance, time-resolved fluorescence spectrum, and density functional theory calculation. Moreover, due to the presence of a morpholine group, the probe was successfully used to monitor Hg2+ and biothiols in the lysosomes of HeLa cells.

A morpholine-functionalized pyrrole-cyanine probe was synthesized via a simple condensation reaction in high yield. This probe exhibits high selectivity toward ClO− on fluorescence and UV–vis spectra in neat aqueous solution. The strong green emission of the probe solution was quenched and the yellow color faded immediately upon the addition of ClO−. The detection limit of the probe for ClO− was 0.165 μM. The mechanism of hypochlorite-induced C C breakage was supposed on the basis of EIS-MS, NMR, and density functional theory (DFT) calculation. Finally, the probe was utilized to image ClO− in lysosomes of living cells.

A novel 'D-π-A' sensor 1 has been designed and prepared via the condensation reaction of 3‑ethyl‑2‑methyl‑1,3‑benzothiazol‑3‑ium iodide and 5‑nitro‑o‑vanillin. Upon treatment with cyanide, sensor 1 exhibited a significant near-infrared (NIR) fluorescence quenching at 663nm. The MS, IR, 1H NMR and DFT methods confirmed that the response of 1 to cyanide is due to the nucleophilic addition reaction, which results in the inhibition of the Intramolecular Charge Transfer (ICT) process in the sensor. Furthermore, sensor 1 was used for the determination of CN- in HeLa cells.

An aggregation-induced emission (AIE) active bis-hydrazone in the aqueous medium is designed and prepared, which can be used as a multi-probe that selectively detects Cu2+, Zn2+, and Hg2+ by monitoring the changes in absorption and fluorescence spectral patterns. Results show that Zn2+ and Hg2+ can enhance the fluorescence in EtOH solution. The addition of Cu2+ strongly improves absorption in the visible range. In contrast to the fluorescence of 1 + Zn2+, the fluorescence of 1 + Hg2+ can be maintained in the presence of water. The crystal structure of the Hg(II) complex based on 1 is further determined through X-ray crystallographic analysis. To test the practical use of the probe, the determination of Hg2+ in real water samples was also evaluated.

A simple chemosensor, namely, ethyl 5-(isonicotinoylimino)methyl-2,4-dimethyl-pyrrole-3-carboxylate (1), was synthesized and characterized. Probe 1 exhibited great selectivity when used as an off–on fluorescent sensor for Zn2+. Moreover, 1 can be used as a colorimetric probe for the detection of Cu2+ in semiaqueous media. The putative binding mechanism of 1 with its target analytes was confirmed through UV-Vis absorption analysis, fluorescence measurements, mass spectroscopy, 1H NMR analysis, and density functional theory calculations. In addition, the resulting 1 + Cu2+ complex can be used as a colorimetric sensor for pyrophosphate. Probe 1 is successfully applied in monitoring intracellular Zn2+ in the glioma cell line U251.

A simple chemosensor, namely, N-((quinolin-8-yl)methylene)acetohydrazide (1) was synthesized and used as an off–on fluorescence sensor, which exhibits high selectivity toward Zn2 + in aqueous media. The probe has large Stokes shift of > 200 nm, and its detection limit for Zn2 + is 89.3 nM. The binding process was confirmed through UV–vis absorption analysis, fluorescence measurements, mass spectroscopy study, 1H NMR spectra and density functional theory calculation. The crystal structures of Zn2 +, Ni2 +, and Cu2 + complexes based on 1 were determined through X-ray crystallographic analysis. The fluorescent probe was then applied to monitor intracellular Zn2 + in HeLa cells.

A simple Schiff-base fluorescent chemosensor (1) was synthesized by the reaction of 3-amino-pyrazine-2-carbohydrazide and 7-diethylamino-3-formylcoumarin; the sensor 1 displayed a notable green emission at 524 nm in DMSO and an aggregation-induced ratiometric emission (AIRE) at 555 nm in an almost buffered aqueous media (0.5% DMSO content). The AIRE of 1 was quenched following binding to Zn2+ ions, while the fluorescence emission in the far-red region was evidently enhanced at 628 nm. Notably, the ratiometric signal output could be utilized to specifically distinguish Zn2+ among various metal ions. Moreover, the 1-Zn2+ complex was effectively employed as a fluorescent ratiometric chemosensor for pyrophosphate (PPi) detection. The detection limit was 3.52 μM and 2.45 μM for Zn2+ and PPi, respectively. The binding mechanism was evaluated by 1H NMR, ESI-MS, single-crystal X-ray diffraction, TEM, time-resolved fluorescence spectrophotometry, and density functional theory studies. Overall, owing to its sensitive fluorescence behavior, cell imaging studies demonstrated that this sensor is capable of sensing Zn2+ and PPi in living cells.

A new morpholine functionalized coumarin-based fluorescent probe 1 was easily synthesized. The probe realized the sequentially detecting of Cu2+ and H2S in the HEPES buffer solution (20 mM, pH = 5.0). It made a turn-off fluorescence response to Cu2+ by using a complex formation with a 2:1 binding mode, and the resulting complex was able to detect H2S according to the displacement approach with a turn-on fluorescence response. The detecting limits of probe 1 for Cu2+ and 1–Cu2+ system for H2S were calculated to be 26 nM and 88.5 nM, respectively. This “on-off-on” recognition process was demonstrated by ultraviolet–visible spectroscopy, fluorescence spectroscopy, using proton nuclear magnetic resonance studies, electrospray ionization mass spectroscopy, single crystal X-ray diffraction, and using density functional theory calculations. In addition, both cell imaging and co-staining experiments showed that the probe could be utilized to visually detect Cu2+ and H2S in lysosomes.

An aggregation-induced emission (AIE)- and intramolecular charge transfer (ICT)-based probe 1 (7‑hydroxy‑3‑(3‑methyl‑isoxazol‑5‑yl)‑chromen‑2‑one) that is highly selective for N2H4 has been synthesized, exhibiting a ‘turn-on’ response toward N2H4 in CH3CN/H2O solution. The detection limit of the probe was 2.90 ppb, which was evidently lower than the threshold limit value (10 ppb) recommended by the Environmental Protection Agency. Notably, the sensor could be used for the detection of N2H4 in living cells.

The fluorescent probes with good water-solubility, long-wavelength emission and large Stokes shift are greatly desirable for in vivo detection. Herein, we designed a novel 1,8-naphthalimide-based near-infrared (NIR) optical and fluorescent probe (NTC) for sensing cysteine (Cys). Using acrylate as the recognition site, the probe demonstrated high selectivity and sensitivity for Cys with a low detection limit (0.093 μM) in aqueous buffer solution due to the excellent water-solubility. Upon the reaction with Cys, the recovery of intramolecular charge transfer (ICT) in the probe led to about 40-fold fluorescence enhancement. Furthermore, the reaction result was investigated by 1H NMR, and HRMS analyses, and the sensing mechanism was validated by quantum calculations. Finally, NTC was applied to image exogenous and endogenous Cys in HeLa cells and zebrafish selectively, implying that the probe possessed great potential application in biological fluorescence sensing.

A quinoline-based hydrazone, namely, bis((quinolin-8-yl)methylene)carbonohydrazide (1), has been designed and synthesized, which could be used as a dual probe for selective recognition of Co2+ and Zn2+ by monitoring changes in absorption and fluorescence spectral pattern, respectively. The detection limits of 1 for these two ions are 0.21 and 0.66 μM, respectively. The complex formation between 1 and Co2+/Zn2+ is responsible for the detection process, as confirmed through several spectral methods and DFT calculations. The application of the as-synthesized sensor is demonstrated in Zn2+ imaging in living cells.

A simple chemosensor, 6-(1H-pyrrol-2-yl)-5,6-dihydro-benzo[4,5]imidazo[1,2-c]quinazoline (1), was synthesized via simple nucleophilic addition reaction coupled with Schiff base condensation. The probe 1 is aggregation-induced emission-active and could be used as an on–off fluorescence sensor toward Cu2+ in H2O/CH3CN (99.5%, v/v) solution. Furthermore, the resultant Cu2+ complex selectively responded to pyrophosphate (PPi) among various anions based on fluorescent on–off signal. In addition, the probe could be used for detecting Cu2+ and PPi in HeLa cells.

A coumarin-based sensor C1, namely 3-acetoacetylcoumarin was designed, synthesized and applied for hydrazine detection. Hydrazinolysis of the chemosensor gives a fluorescent coumarin-pyrazole product C1-N2H4 [3-(3-methyl-1H-pyrazol-5-yl)coumarin], and thus resulting in a prominent fluorescence off-on response toward hydrazine under physiological conditions. The probe is highly selective toward hydrazine over cations, anions and other biologically/environmentally abundant analytes. The detection limit of the probe is 3.2ppb. The sensing mechanism was supported by 1H NMR, IR, MS and DFT calculation. The application of the fluorescent probe in monitoring intracellular hydrazine in glioma cell line U251 was also demonstrated.

Two rhodamine-based Hg2 + probes L1 and L2 were prepared and confirmed by NMR, MS and crystal data. The sensing behavior of these probes was studied by UV–visible and fluorescence spectroscopy. The probe L1 couldn't be widely applied in aqueous media or mixed media because of its poor solubility. However, the probe L2 displayed selective and sensitive fluorescence enhancement response to Hg2 + at physiological pH value for biological use. The selectivity of this system for Hg2 + over other metal ions was remarkably high, and its sensitivity was at ppb level. The probe L2 responded rapidly to Hg2 + in aqueous solutions with a 1:1 stoichiometry and was successfully applied to image Hg2 + in living cells.

Excessive accumulation of iron in the body can lead to organ injury. Some flavonoids which possess high affinity to iron can be used as iron chelators for curing iron overload diseases such as haemochromatosis. In this article, the effects of baicalin and quercetin on different mouse tissues (liver, kidney and heart) afflicted with iron overload-induced injury were studied. It was found that after administration of 500 mg kg⁻¹ iron dextran for 45 days, the degree of oxidative injury in the three organs was different. When iron dextran-induced iron-overloaded mice were fed a diet containing baicalin or quercetin (1% w/w), both flavonoids showed significant effects in suppressing iron overload-induced injury. The efficiencies of both flavonoids on different tissues varied. Both flavonoids caused a significant decrease of iron content in liver and kidney tissues but not in the heart, whereas the flavonoids were more efficient in inhibiting the increase of carbonyl content and the thiobarbituric acid reactive substance levels in heart tissues. The results indicate that the protective effects of baicalin and quercetin on different tissues of iron-overloaded mice are different.

1-Cyclohexyl-3-tosylurea (HL) and its two complexes, ML 2 ·2H 2 O [M Ni( 1 ), and Cd( 2 )], have been synthesized and characterized on the basis of elemental analyses, molar conductivities, IR spectra and thermal analyses. In addition, the DNA-binding properties of the ligand and the two complexes have been investigated by electronic absorption, fluorescence, CD spectroscopy and viscosity measurements. The experiment results suggest that the ligand and its two complexes bind to DNA via a groove binding mode, and the binding affinity of the complex 2 is higher than that of the complex 1 and the ligand.

Third instar larvae of the cotton bollworm (Helicoverpa armigera) were reared with artificial diet containing a Bacillus thuringiensis - abamectin (BtA) biopesticide mixture that resulted in 20% mortality (LD20). The adult male survivors from larvae treated with BtA exhibited a higher percentage of “orientation” than control males but lower percentages of “approaching” and “landing” in wind tunnel bioassays. Adult female survivors from larvae treated with BtA produced higher sex pheromone titers and displayed a lower calling percentage than control females. The ratio of Z-11-hexadecenal (Z11–16:Ald) and Z-9-hexadecenal (Z9–16:Ald) in BtA-treated females changed and coefficients of variation (CV) of Z11–16:Ald and Z9–16:Ald were expanded compared to control females. The peak circadian calling time of BtA-treated females occurred later than that of control females. In mating choice experiment, both control males and BtA-treated males preferred to mate with control females and a portion of the Bt-A treated males did not mate whereas all control males did. Our Data support that treatment of larvae with BtA had an effect on the sex pheromone communication system in surviving H.armigera moths that may contribute to assortative mating.

UNLABELLED Loop-mediated isothermal amplification (LAMP) allows a rapid amplification of nucleic acids under isothermal conditions. It can be combined with a rhodamine-based dual chemosensor for much more efficient, field-friendly detection of Listeria monocytogenes. In this report, LAMP was performed at 63 °C for 10 min, followed by a rapid reaction of DNA amplification and the byproduct, pyrophosphate ion, with a rhodamine-based dual chemosensor and Cu(2+) is visualized as a disappearance of red color. The detection limit of L. monocytogenes by the LAMP-chemosensor was 8 to 10 cells per reaction tube, and the total assay time including 10 min for rapid DNA extraction was approximately 30 min. Data on naturally contaminated raw milk samples indicated that the LAMP method was highly specific and sensitive, giving 100% concordance with the ISO 10560 reference method. The results showed that the LAMP-chemosensor method has the advantages of better sensitivity and speed and less dependence on equipment than the standard Polymerase Chain Reaction for specifically detecting low levels of L. monocytogenes DNA, and this can be useful in the field as a routine diagnostic tool. PRACTICAL APPLICATION The LAMP-chemosensor method reported here provided a powerful tool for detection of L. monocytogenes in raw milk samples due to its specificity, sensitivity, and rapidity.

A turn-on chemosensor L1, which exhibits high selectivity and sensitivity toward Hg(2+) over other common metal ions in aqueous media under a physiological pH window via a 1:1 binding mode, had been synthesized and characterized. L1 provides good fluorescent imaging of Hg(2+) in living cells. Particularly, we adopted the "micro computed tomography (MCT)" technology, successfully demonstrating the method of Hg(2+) sensing by L1 in cell lines, also the cell permeability of L1 and its imaging position in the cells.

A new complex, manganese(II) azide complex with N-methylimidazole, has been synthesized and characterized by elemental analysis, IR spectra and single crystal X-ray studies. Absorption spectroscopy, emission spectroscopy, viscosity measurements and CD spectroscopy have been used to investigate the binding of the complex with calf thymus DNA (CT-DNA). The intrinsic binding constant K b of the complex with DNA was obtained by electronic absorption titration; the value is consistent with the result by fluorescence titration method. The spectroscopic studies together with viscosity measurements support the claim that the title complex bonds to CT-DNA by a groove mode. Control cleavage experiments using pBR 322 plasmid DNA which suggest minor groove binding for the complex.

Four novel water-soluble complexes of Ln(III) with gatifloxacin (HGA), [La(HGA)3Cl3] x 2H2O, [Nd(HGA)3Cl3] x 2H2O, [Eu(HGA)3Cl3] x 2H2O, [Tb(HGA)3Cl3] x 2H2O, have been synthesized and characterized by elemental analyses, molar conductivities, IR spectra, fluorescence spectra, and thermogravimetry/differential thermal analysis (TG-DTA). In addition, the DNA-binding properties of the ligand and its complexes have been investigated by absorption, fluorescence spectra, and viscosity measurements. The experimental results indicated that the complexes and ligand bind to DNA via groove binding mode.