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Our continuous study of the dry fruits of Garcinia xanthochymus led to the isolation and structural characterization of four new prenylated acylphloroglucinols, xanthochymusones J-M (1-4), together with the known polycyclic polyprenylated acylphloroglucinols, garciniagifolone A (5) and garcinialiptone A (6). Their structures were elucidated by interpretation of NMR and MS spectroscopic data. Compound 1 bearing a similar core to that of hulupinic acid should be derived via oxidization and ring contraction of prenylated acylphloroglucinol. The inhibitory activities of all the compounds against three human hepatocellular carcinoma cell lines Huh-7, Hep 3B, and Hep G2 were evaluated, and compounds 4 and 5/6 exhibited moderate cytotoxic activities against Hep G2 cells with IC

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

The aim of this study was to evaluate the efficacy and safety of motherwort injection (MI, Yi mu cao) in preventing post-abortion hemorrhage and promoting uterine retraction after induced abortion surgery.In this multi-center randomized controlled trial undertaken between September 2014 and August 2016, 408 child-bearing age women who underwent induced abortion surgery and randomly assigned to two groups: MI group who received intramuscular MI treatment (n = 207) and no-treatment group (n = 201). The volume of vaginal bleeding and its duration were used as primary end points; and uterine size and dimension were measured as secondary end points. Blood coagulation indices, routine blood and adverse events were recorded to evaluate the safety.The efficacy analysis was based on 366 patients. No significant difference were found in baseline characteristics between the two groups (P 0.05). The amount of vaginal bleeding and duration of bleeding were significantly reduced in MI group compared with on-treatment group in Full Analysis Set (FAS) and Per Protocol Set (PPS) populations (P 0.001). The volume and perimeter of the uterine dimensions in MI group were smaller than no-treatment group (P 0.001). No significant abnormal vital signs were observed. Only 1 case of mild, transient erythema was found in MI group.MI could reduce post-abortion hemorrhage and improve uterine retraction in women undergoing surgical induced abortion, without serious adverse events. It was a safe and effective treatment in preventing post-abortion hemorrhage after induced abortion.

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

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

A novel pyrazine hydrazone 1 has been designed and synthesized, which acts as a multiprobe for selective detection of Al3+, Mg2+, and Zn2+ in DMSO solution based on fluorescent enhancement with three different emission colors. The higher affinity of 1 toward Al3+ and Zn2+ compared with Mg2+ facilitates the establishment of a simple ratiometric fluorescent method for the detection of Al3+ and Zn2+ based on the 1 + Mg2+ system. Conversely, probe 1 selectively recognized Al3+ in DMSO-H2O cosolvent with a turn-on response, and the resultant 1 + Al3+ complex could determine F− via a fluorescence quenching signal. In addition, the probe is applied for imaging of Al3+ and F− in living cells.

A series of β-β directly linked Bodipy oligomers (D1, D2, D3 and T1) based on different monomers are synthesized and the crystal structures, photophysical properties, singlet oxygen (1O2) generation abilities, bioimaging and phototoxicity are investigated. Single-crystal X-ray analyses of D1 and D2 indicate the distorted orthogonal conformation of two linked Bodipy planes. In comparison with the meso-β analogues, the β-β dimers exhibit red-shifted spectroscopy bands, strong fluorescent emission but modest 1O2 quantum yields due to the distorted orthogonal structures and electron interaction, which is demonstrated by single-crystal analysis, spectroscopy measurements and quantum calculations. The fluorescence imaging and cytotoxicity assay results indicate that the unsubstituted D1 and D2 with excellent bioimaging performance alongside with obvious phototoxicity are promising candidates in the fields of cell imaging and photodynamic therapy.

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.

Harmful metal ions have received intense attention. In particular, palladium, a rare inner transition metal, is the subject of intense research in light of its catalytic capabilities and the restrictions on the levels of residual harmful metal ions in end products，has attracted wide spread interest from chemists. A near-infrared Pd2+ probe Cy202 has been synthesized that exhibits pronounced fluorescence enhancement in the presence of Pd2+. The Pd2+ recognition properties were examined by using UV–Vis spectroscopy and fluorescence spectroscopy in DMSO/PBS buffer solution (pH 7.40, 8/2, v/v). The solution of the probe exhibits color change turned from yellow to brown upon the addition of Pd2+ while no significant response to other metal ions. The detection limit was calculated as low as 0.52 μM. The probe could be useful for imaging Pd2+ in palladium-containing catalyst and samples.

A simple monocarbazone 1 derived from 2H-benzo[h]chromene-3-carbaldehyde and carbazide exhibited aggregation-induced ratiometric emission upon the addition of water to CH3OH solution (Δλem= 30 nm). Upon Cu2+ treatment, the fluorescence emission of 1 displayed a significant red shift in both CH3OH and H2O solutions. In addition, 1 can detect Hg2+ through the fluorescence quenching in H2O solution. The response mechanism to Cu2+ involved an intermolecular charge transfer coupled with a metal-induced assembly, whereas that to Hg2+ was probably due to a photo-induced electron transfer coupled with metal-induced assembly, which were thoroughly investigated by spectral methods and theoretical calculation. In addition, the sensor could successfully detect the corresponding ions in HeLa cells.

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 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.

A new fluorescein-based probe (Py-F) was designed and synthesized to develop an optical and fluorescent sensor for biological thiols. Py-F possessed the thiol-responsed disulfide group and displayed selectivity and sensitivity for glutathione (GSH) and cysteine (Cys) over homocysteine (Hcy) in the CH3CN/PBS buffer solution, and the fluorescence detection limit was calculated to be 0.12 μM and 0.13 μM, respectively. Besides, the recognition mechanism was explained by density functional theory (DFT) calculation, and confirmed by mass spectroscope measurement. Furthermore, the thiols detection application in cellular imaging assays indicated that the probe has appreciable cell permeability and can serve as a fluorescent probe for detecting biothiols in living cells.

A novel pyrene-based Schiff base derivative, 1, was synthesized by one-pot reaction. This compound was then used for aggregation emission enhancement and as fluorescence turn-on sensor toward Cu2+ in semi-aqueous solution based on metal-induced self-assembly. Detection limit of Cu2+ ion was 35 nM. The fluorescent sensor was further applied in monitoring intracellular Cu2+ 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, 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.

In this study, we developed a fluorescence-enhanced probe (1) based on a simple Schiff-based condensation reaction for Cu2+ selection. We investigated its distinct recognition mechanism through mass spectra, 1H NMR studies, and DFT calculations. The imaging and costaining experiments indicated that the probe could successfully image lysosomal Cu2+.

A 1,8-naphthalimide hydrazone derivative bearing a pyrrole unit is a highly selective ratiometric fluorescent Cu 2+ probe used to monitor intracellular Cu 2+ in HeLa cells. This probe functions via a unique hydrolysis mechanism through Cu 2+ -promoted electrophilic substitution. Binding is confirmed through UV–vis absorption, fluorescence measurements, mass spectroscopy, IR, X-ray single crystal diffraction, and DFT calculation.

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.

Monitoring levels of SO2 and its derivatives, including sulfite (SO32−) and bisulfite (HSO3−) ions, in biological systems is of great importance because their aberrant concentrations in cells may cause several diseases. Aggregation-induced-emission (AIE) active probes are exhibited good photophysical properties in aqueous solution, and have been applied in many fields. Herein, we report benzo[h]chromene aldehyde (1) with aggregation-induced ratiometric emission (AIRE) that showed a blue emission in a solution, whereas in an aggregate state, a green emission with 43-nm Stocks shift was observed. Furthermore, this green AIRE was specifically quenched using HSO3− under physiological conditions owing to the formation of a water-soluble and non-emissive product after the addition of bisulfite to the aldehyde group of 1. Finally, the imaging experiments indicated that probe 1 could be utilized to detect exogenous HSO3− in HeLa cells.

A rhodamine-2-thioxoquinazolin-4-one derivative ( R1 ) has been synthesized by an addition-elimination reaction of rhodamine 6G ethylenediamine with methyl 2-isothiocyanatobenzoate, which exhibits high selectivity and sensitivity as a fluorescent sensor toward Fe 3+ under physiological conditions. Moreover, R1 could sense Fe 3+ by “naked eye” with a color change from colorless to yellow. To test the practical use of the probe, the determination of Fe 3+ in real water samples was evaluated. The application of the fluorescent sensor in monitoring intracellular Fe 3+ in glioma cell line U251 has also been demonstrated. In addition, single crystal structures of R1 ·1·5H 2 O·0·5CH 3 CN, as well as the possible intermediate of R1 with Ag + and Hg 2+ ions were reported.

A rhodamine derivative (R1) has been synthesized by an additive reaction of rhodamine 6G hydrazide with methyl 2-isothiocyanatobenzoate, which exhibits high selectivity and sensitivity as a fluorescent sensor toward Cu2+ under physiological conditions. The detection limit of Cu2+ ion is 47.2 nM. Moreover, R1 could sense Cu2+ by “naked eye” with a color change from colorless to pink. This selective signaling behavior is not affected by other canions that might be present in the environmental samples. The application of the fluorescent sensor in monitoring intracellular Cu2+ in HeLa cells was also demonstrated.

World-wide wetlands are experiencing increasing pressure from economic development, including the conversion of wetlands to agriculture. While it is assumed that this land use change will have negative impacts on local biodiversity, the specific impacts of agriculture on insect biodiversity in wetland ecosystems are poorly understood. To address this knowledge gap we investigated insect communities in the multi-land use Wuxijiang National Wetland Park, quantifying both species diversity and functional diversity. Four species diversity indexes and twelve functional diversity indexes were used to describe species diversity and functional diversity respectively. We provide three primary results: 1.) Species diversity and functional diversity of natural wetland plants is not necessarily higher than artificial economic plants; 2.) Species diversity indexes are generally correlated with functional diversity indexes; and 3.) Straw mulch cultivation can increase the species diversity and functional diversity of insect.

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 novel rhodamine-based hydrazone (1) bearing morpholine as the lysosome-locating group was synthesized via Schiff base condensation. Probe 1 exhibited a remarkable fluorescent turn-on response over the pH range of 4.0–3.0, which corresponds to the acidic microenvironment of lysosomes in cancer cells. The results of fluorescence cell imaging and a subcellular localization study conducted with HeLa and HepG2 cancer cells and 293T normal cells revealed the good cell membrane permeability and potential applications of 1 in the selective differentiation of cancer cells from normal cells.

A novel dicyanomethylene-4H-pyran-based sensor bearing 2-thiophenecarbonyl as a masking group was established for the detection of cyanide anions. Upon the addition of cyanide, sensor 1 manifested a near-infrared emission band at 717 nm, with an extremely large red-shift (~180 nm) in the absorption spectrum. It also showed an obvious color change from yellow to green. Sensor 1 was used to sensitively measure CN− with low detection limit of 1.44 μM. The stoichiometric ratio between probe and CN− were determined as 1:1, with the association constant of 7.87 × 102 M−1. The reaction mechanism was investigated by ESI-MS, 1H NMR, HPLC, and density functional theory methods. Results indicate that the nucleophilicity of the cyanide catalyzes the elimination of 2-thiophenecarbonyl, which strengthens the intramolecular charge transfer effect of the dicyanomethylene-4H-pyran fluorophore. Furthermore, sensor 1 was found to be efficient in detecting cyanide in the intracellular region of MCF-7 cells.

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 novel hemicyanine-based near-infrared (NIR) fluorescence probe CY1OH2S for Hg2+ ions detection was synthesized, which can selectively and sensitively responds to Hg2+ ions based on the Hg2+-promoted deprotection of thioacetal. The probe exhibits good response and anti-interference performance for Hg2+ ions based on the fluorescence enhancement in the NIR region under physiological conditions. The detection limit of probe CY1OH2S for Hg2+ ions was as low as 0.32 μM. Probe-coated test paper was fabricated as a “naked-eye” indicator for Hg2+ ions in water samples. In addition, probe CY1OH2S exhibited good cell permeability and was successfully applied in living cells by NIR fluorescence imaging.

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.