Determination of carboxylesterase by fluorescence probe to guide detection of carbamate pesticide.

A carboxylesterase fluorescent probe (Probe 1) was developed for determination of carboxylesterase to guide detection of carbamate pesticide. The probe uses benzothiazole as fluorescence group and phenyldimethyl carbamate as recognition group. The solution of the fluorescent probe gradually changes from light blue to dark blue as the concentration of carbamate pesticides increases. The concentration of carbamate pesticides can be quickly calculated according to the colour of the probe solution through Get Color software on a smartphone. It showed that Probe 1 can be used as a rapid detection tool to achieve rapid detection of carbamate pesticides in juice samples without professional personnel and equipment. Furthermore, the probe has been successfully used to detect carbamate pesticides in fruit juice and vegetable juice.

A dual-function fluorescent probe for the detection of pH values and formaldehyde.

A dual-function fluorescent probe (Probe 1) was developed in this work for the separate detection of pH value and formaldehyde (HCHO). Probe 1 could recognize HCHO and the pH value from the amino group. The colour of the probe solution was changed from grey blue to light blue with the increase in the pH value, and luminous intensity became larger with the increase in formaldehyde concentration. The curve function relationship between fluorescence intensity and the pH value was also determined. A smartphone containing a colour detector for imaging was used to record the values of the three primary colours (R value, G value, and B value) for the probe solution in formaldehyde. Importantly, there was a linear functional relationship between the B*R/G value with HCHO concentration. Therefore, the probe could be used as a rapid tool for the detection of formaldehyde. More importantly, Probe 1 was successfully used to detect formaldehyde in an actual distilled liquor sample.

Application of a luminous intensity variation fluorescent probe for the detection of ferric ions.

A luminous intensity variation fluorescent probe (Probe 1) for the detection of ferric ion was developed. The quantitative range of Fe3+ content detected was 0-600 µM with the limit of detection at 0.76 µM. Furthermore, after 20 min of Fe3+ addition, the intensity of the luminescence of Probe 1 solution gradually decreased with increase in Fe3+ concentration. In addition, the B and G values of these images showed a linear relationship with Fe3+ concentration (0-500 µM). Probe 1 was successfully used for the rapid determination of Fe3+ concentration in real samples. This study demonstrates that Probe 1 is an excellent tool for the rapid determination of Fe3+ content in real samples using a smart phone without professional equipment.

A novel fluorescence probe for the detection of water content in organic solvents and the distinction between deuterated and nondeuterated reagents.

A novel D-π-A type fluorescent probe (probe 1) was developed for water content detection in organic solvents. By analyzing the relationship between fluorescence and water content, the probe was successfully applied to determine trace water content in tetrahydrofuran, ethyl acetate, 2-butanone, acetone, dimethylformamide, and acetonitrile. High water content in THF and ethyl acetate was associated with a gradual colour change from yellowish green to earthy yellow. The red/green value had a linear relationship with the water content in THF and ethyl acetate. There was a linear relationship between the red/blue value and water content in 2-butanone and acetone. Furthermore, probe 1 could be used for human serum albumin detection. Unexpectedly, probe 1 had a different colour response in deuterated and nondeuterated solvents, and had different fluorescence intensity and fluorescence emission wavelength. Probe 1 is rare tool that can distinguish between deuterated and nondeuterated reagents.

Discovery of Hyrtinadine A and Its Derivatives as Novel Antiviral and Anti-Phytopathogenic-Fungus Agents.

Plant diseases caused by viruses and fungi have a serious impact on the quality and yield of crops, endangering food security. The use of new, green, and efficient pesticides is an important strategy to increase crop output and deal with the food crisis. Ideally, the best pesticide innovation strategy is to find and use active compounds from natural products. Here, we took the marine natural product hyrtinadine A as the lead compound, and designed, synthesized, and systematically investigated a series of its derivatives for their antiviral and antifungal activities. Compound 8a was found to have excellent antiviral activity against the tobacco mosaic virus (TMV) (inactivation inhibitory effect of 55%/500 µg/mL and 19%/100 µg/mL, curative inhibitory effect of 52%/500 µg/mL and 22%/100 µg/mL, and protection inhibitory effect of 57%/500 µg/mL and 26%/100 µg/mL) and emerged as a novel antiviral candidate. These compound derivatives displayed broad-spectrum fungicidal activities against 14 kinds of phytopathogenic fungi at 50 µg/mL and the antifungal activities of compounds 5c, 5g, 6a, and 6e against Rhizoctonia cerealis are higher than that of the commercial fungicide chlorothalonil. Therefore, this study could lay a foundation for the application of hyrtinadine A derivatives in plant protection.

Dehalogenative Cross-Coupling of gem-Difluoroalkenes with Alkyl Halides via a Silyl Radical-Mediated Process.

Herein, we describe a convenient general protocol for monofluoroalkenylation reactions of alkyl bromides involving cooperative visible-light photoredox catalysis and halogen abstraction. Mechanistic experiments showed that the products were generated by selective cross-coupling of aliphatic radicals with fluoroalkenyl radicals. Silyl radical-mediated halogen abstraction enabled the protocol to be used for the monofluoroalkenylation of a broad range of alkyl and heteroaryl halides. The protocol could be carried out on a gram scale and was applied to cholesterol, indicating its utility for late-stage monofluoroalkenylation reactions.

Discriminative detection of mercury (II) and hydrazine using a dual-function fluorescent probe.

A dual-function fluorescent probe (Probe 1) was developed for discriminative detection of Hg2+ and N2 H4 . Probe 1 could discriminatively detect Hg2+ and N2 H4 through two different reaction sites, with the mechanism for Probe 1 for Hg2+ depending on a desulfurization reaction and for N2 H4 depending on the Schiff-base reaction. N2 H4 had minimal effect on Hg2+ detection in dimethyl sulfoxide (DMSO)/H2 O solution, but Hg2+ could interfere with N2 H4 detection in DMSO/buffer solution. Different concentrations of Hg2+ and N2 H4 resulted in different blue shades of Probe 1 test strips, and the shade of blue was different with the same concentration of Hg2+ or N2 H4 , as observed under ultraviolet light at 365 nm wavelength.

Synthesis and insecticidal activity studies of novel phenylpyrazole derivatives containing arylimine or carbimidate moiety.

Phenylpyrazole insecticides are successful for crop protection and public hygiene by blocking gamma-aminobutyric acid (GABA)-gated chloride channels and glutamate-gated chloride (GluCl) channels. A series of novel phenylpyrazoles containing arylimine or 1-methoxyaryl groups were designed and synthesized. The addition reaction of methanol to the imines 1-11 was investigated and the cayno addition products 13-15 were obtained. The compounds 1-15 were confirmed by 1H NMR and elemental analysis. The results of bioassay indicated that some compounds exhibited comparable bioactivity to fipronil against a broad spectrum of insects such as bean aphid (Aphis craccivora), mosquito (Culex pipiens pallens), diamondback moth (Plutella xylostella) and Oriental armyworm (Mythimna separata). Especially, the foliar contact activity against bean aphid of compound 7 at 10 µg mL-1 was 68%, the larvacidal activity against mosquito of compounds 5, 13 and 15 at 0.0025 µg mL-1 was 100%, the larvacidal activity against diamondback moth of compounds 9 and 11 at 0.05 µg mL-1 was 100%, the larvacidal activity against Oriental armyworm of compound 9 at 1 µg mL-1 was 100%. The 3-cayno moiety on pyrazole ring was essential for the high insecticidal activities against bean aphid, diamondback moth and Oriental armyworm, while the 3-carbimidate moiety on pyrazole ring was crucial to the excellent high insecticidal activities against mosquito.

A Magnetic Zeolitic Imidazolate Framework Nanohybrid for Fast and Efficient Extraction of Clothianidin, Imidacloprid, Acetamiprid, and Thiacloprid in Water.

A magnetic zeolitic imidazolate framework nanohybrid (Fe3O4/ZIF-8) was synthesized and applied as an efficient magnetic solid-phase extraction (MSPE) adsorbent for fast adsorption and separation of clothianidin, imidacloprid, acetamiprid, and thiacloprid from various water samples. Fe3O4 and ZIF-8 were combined via a simple modified in situ method and the obtained nanohybrid (Fe3O4/ZIF-8) showed both excellent adsorption capacity and convenient magnetic property. ZIF-8 was found to play a dominant role in adsorbing the analytes and π-π interaction was found to be the main adsorption mechanism of analytes by Fe3O4/ZIF-8. Parameters affecting the MSPE efficiency, such as the Fe3O4 amount loaded onto the ZIF-8, salt and pH of the sample solution, extraction time, and the type and volume of desorption solvent, were systematically evaluated. Under the optimum conditions, the developed MSPE coupled with LC-MS/MS achieved good linearities (R² > 0.9940) in the range of 10-800 µg L-1 with low limits of detection (0.03-0.3 µg L-1) and satisfactory recoveries of 79.5-108.2% with relative standard deviations (RSDs) <10%. The method was successfully applied to monitor various water samples and conclusively highlighted the excellent flexibility and practicability of Fe3O4/ZIF-8 for analyzing emerging environmental contaminants in various types of water samples.

Serum albumin as a significant prognostic factor in patients with malignant pleural mesothelioma.

Our aim was to evaluate the prognostic role of the pretreatment serum albumin level in patients with malignant pleural mesothelioma (MPM) receiving platinum-based systemic chemotherapy. From 1995 to 2013, a total of 97 patients receiving platinum-based systemic chemotherapy for newly diagnosed MPM were enrolled. All clinical information and laboratory results were retrospectively collected from the medical records. The Kaplan-Meier method was used to calculate survival. The Cox proportional hazards model was used to identify significant independent prognostic factors for predicting survival. In total, 34 of the 97 patients (35.1 %) had hypoalbuminaemia (albumin ≤ 35 g/l). The 1-year overall survival rate was 44.1 % for patients with hypoalbuminaemia and 72.0 % for patients with a normal albumin level. Multivariate analysis indicated that pretreatment albumin was an independent prognostic factor in MPM. Patients with hypoalbuminaemia had a greater risk of death than those with a normal albumin level [hazard ratio (HR) 1.778; 95 % confidence interval (CI) 1.504-2.998; P = 0.031]. When albumin was entered as a continuous variable in the Cox regression model, the HR of death was significantly decreased by 9.8 % (95 % CI 0.851-0.956) for each 1-g/l increment. The pretreatment serum albumin level is a simple, inexpensive and easily measurable marker with prognostic significance in MPM patients treated with platinum-based systemic chemotherapy.

Research Progress on the Application of Multifunctional Amino Derivative Fluorescent Probes in Food, the Environment, and the Microenvironment.

The amino group is regarded as a multifunctional recognition group in fluorescent probes. It is nucleophilic, a strong electron-donating group and is a polar group with active hydrogen. Based on these characteristics, amino-based fluorescent probes combined with various fluorescent precursors have been constructed, with excellent sensing performance and low cytotoxicity. These probes have significant application value in the detection of food, living cells and organisms. Here, the relevant studies on amino fluorescent probes from 2016 to 2024 are systematically reviewed and their molecular design principles, recognition mechanisms and applications are described. These studies included 14 on exogenous and endogenous formaldehyde detection, five that detected polarity changes in the external environment and organelles in vivo, four intracellular mitochondrial and lysosomal viscosity detections, seven physiological environment and intracellular pH detections, seven metal ion detections in biological and environmental systems and four rapid detections of the hypochlorite anion (ClO-) in a variety of physiological processes and cells. The application scope of amino fluorescent probes is constantly expanding at present but, research progress in multiple application fields has not been summarized. This article mainly reviews the latest progress in amino fluorescent probes in the fields of food, the environment and the microenvironment, as well as looking forward to the development prospects of these fluorescent probes. Improving the reactivity of amino recognition groups and visual detection may become hot issues in future research.

A colorimetric probe for the detection of hydrazine and its application.

A colorimetric probe was developed to detect N2H4 content based on the colour change in natural light, and the recognition mechanism is the N2H4 cutting the ester bond of probe 1. As the N2H4 concentration increases, the Ultraviolet absorption ratio (A352nm/A505nm) of the probe solution was gradually increases, and the colour of the solution changed from colourless to pink under natural light. The detection limit of probe 1 for N2H4 was 0.1 µM. The probe can also be applied to test paper detection, and the test paper of probe was changed from colourless to fluorescent yellow under UV light as the concentration of N2H4 increased. There was a linear functional relationship between the RGB (Red, Green, Blue) values of the photos and the N2H4 concentration. Probe 1 is a rapid detection tool for N2H4 concentration using a smartphone. Furthermore, the probe can also be used to detect N2H4 in tap water, tea and apple juice.

A dual-site fluorescent probe for the detection of γ-glutamyl transpeptidase activity and its application in garlic.

Developing convenient γ-glutamyl transpeptidase (GGT) activity detection methods is of great significance for soaking Laba garlic and human diseases detection. A dual-site fluorescent probe (probe 1) was developed for detection the activity of GGT. Probe 1 could recognize GGT by the enzymatic hydrolysis of peptide bond by GGT. There has a linear relationship between the fluorescence intensity of probe 1 at 416 nm and the activity of GGT. And the color of the probe solution gradually changed from colorless to blue with the increase of GGT activity under 365 nm ultraviolet light. Importantly, it has a linear relationship between the activity of GGT and the blue (B) value of probe solution photo. Therefore, probes can serve as a convenient tool for detecting GGT activity. More importantly, the probe has been successfully applied to detect of GGT activity in garlic.

Ultrasonic synthesis of magnetic covalent organic frameworks and application magnetic solid phase extraction for rapid adsorption of trace bisphenols in food samples.

A simple ultrasonic synthesis strategy was developed for a novel magnetic covalent organic framework. Firstly, the Fe3O4 nanoparticles were encapsulated by imine-type COF, which generated by the Schiff reaction of 4,4',4''-(1,3,5-Triazine-2,4,6-triyl)-trianiline (TAPT) and tris(4-formylphenyl)-amine (TFPA) using ultrasonic synthesis method within 2 h. The synthesised nanocomposites showed a sizeable specific surface area, and high adsorption capacity. A fast, sensitive MSPE method with Fe3O4@TAPT-TFPA-COF as adsorbent for analysing bisphenol compounds was developed. This method's advantages were simple operation, short extraction time, and avoidance of the use of centrifugal equipment. The method validation indicate that this method exhibited superior linearity, and detection limits range between 0.33 and 0.60 µg L-1. The recoveries of BPs ranged from 74.7 % to 107.0 %, with relative standard deviations of less than 3.8 % in water, milk, vinegar, and soy sauce samples. The proposed method was successfully applied for extracting BPs in food samples.

A colorimetric fluorescent probe for the detection of carboxylesterase and carbamate pesticides.

A colorimetric fluorescent probe (BTCNA) was developed for the determination of carboxylesterase and carbamate pesticides. The probe used naphthalene-benzothiazole as the fluorescent group and naphthyl acetate as the recognition group. The recognition mechanism of BTCNA for carboxylesterase was based on the enzymatic hydrolysis of naphthyl acetate by carboxylesterase (CES). The test paper of the BTCNA gradually changed from light blue to bright yellow with the increase of CES activity. The probe solution gradually changed from light blue to earth-yellow as the carbaryl concentration increased. There was a linear functional relationship between the R*G (red, green) value of the photo and the CES activity. And a linear functional relationship between the carbaryl concentration and the R*G value of the photo was found. Additionally, BTCNA was successfully used to detect the concentration of carbaryl in actual samples. BTCNA is a rapid detection tool for CES activity and carbamate pesticides using a smartphone.

Research Progress on Multifunctional Fluorescent Probes for Biological Imaging, Food and Environmental Detection.

There has been rapid progress in the development of fast, sensitive, cheap and low-cytotoxicity micro-molecule fluorescent probes for application in various fields, including disease diagnosis, food safety and environmental safety. As an analytical tool, dual-function fluorescent probes with dual-emission responses have attracted considerable attention due to their cost-effectiveness and efficiency over single-function sensors. This review primarily describes research progress on multifunctional probes in terms of the reaction type and coordination type, as well as the general design principles of probes. The analytes include reactive oxygen species (ROS), reactive sulfur species (RSS), harmful cations and anions, etc. Multifunctional probes for food, medical and environmental applications are listed for future research. To improve the development of rapid detection methods, trends and strategies in the development of multifunctional fluorescent probes are also discussed.

A colourimetric fluorescent probe for the sensitive detection of total iron in wine.

As the iron content of wine affects the wine quality, a highly selective and simple detection method is needed to detect the iron content in wine. A colourimetric fluorescent probe (BTBAP probe) for the detection of total iron in wine was developed. The quantitative range of Fe2+/3+ content detected with the probe was 0 to 200 µM with a limit of detection (LOD) of 1.16 µM. After 10 min of Fe2+/3+ addition, the luminescence intensity of the BTBAP probe solution gradually decreased with increasing Fe2+/3+ concentration. Moreover, the B and G values of the luminescence photos were linearly related to the concentration of Fe2+/3+ (0-200 µM). BTBAP probe was successfully applied for rapid determination of the Fe2+/3+ concentration of wine. This work demonstrates that BTBAP probe is an excellent tool for rapid determination of the total iron content of wine using only a smartphone and no other professional equipment.

The recent advance of organic fluorescent probe rapid detection for common substances in beverages.

The beverage industry is confronted with tremendous challenges in terms of quality assurance. The allowed contents of common ingredients such as copper ions, hydrogen sulfide, cysteine and caffeine are stipulated by various governing bodies, and the beverage industry must ensure that it meets these requirements. Due to its unique advantages of high sensitivity, low cost and relatively low toxicity over high-performance liquid chromatography, atomic absorption spectrometry and nanomaterials, the use of organic fluorescent probes for the rapid detection of beverage contents has become a hot research topic. This review summarizes the detection of common substances in wine, tea, mineral water, milk and other beverages. Furthermore, the preparation of test paper and simple colour comparison are discussed to display the rapid qualitative capability of designed probes. To improve the current state of beverage safety, future trends and strategies for fast organic fluorescent probe detection in the beverage industry are also discussed.

Long noncoding RNA NR2F1-AS1 plays a carcinogenic role in gastric cancer by recruiting transcriptional factor SPI1 to upregulate ST8SIA1 expression.

Gastric cancer (GC) is a highly malignant solid tumor of the digestive tract, which is associated with a high mortality rate. Long non-coding RNA (lncRNA) nuclear receptor subfamily 2 group F member 1 antisense RNA 1 (NR2F1-AS1) has been reported to exert a tumor-promoting effect in some types of cancer. The present study aimed to investigate the role of NR2F1-AS1 in GC. The expression levels of NR2F1-AS1 and its potential target gene were measured in GC cell lines. Bioinformatics analysis, an RNA immunoprecipitation assay and a chromatin immunoprecipitation assay were used to determine the binding relationship between NR2F1-AS1 and downstream genes. The effect of NR2F1-AS1 regulatory axis on AGC cell viability, proliferation, migration, invasion and epithelial-mesenchymal transition was evaluated. The results of the present study revealed that the knockdown of NR2F1-AS1 inhibited the proliferation, invasion and migration of GC cells. NR2F1-AS1 also upregulated the expression levels of ST8SIA1 by recruiting transcriptional factor SPI1. Thus, the effects of the knockdown of NR2F1-AS1 on GC cell functions were suggested to occur via regulation of ST8SIA1. In conclusion, the findings of the current study indicated that NR2F1-AS1 may promote the proliferation, invasion and migration of GC cells by recruiting SPI1, to upregulate ST8SIA1 expression. Thus, the regulation of their expression levels may provide a novel direction for the treatment of GC.

A ratiometric fluorescent probe for the detection of ß-galactosidase and its application.

Herein, a coumarin fluorescent probe (Probe 1) was developed for the ratiometric detection of ß-galactosidase (ß-gal) activity. The detection range was 0-0.1 U mL-1 and 0.2-0.8 U mL-1, and the limit of detection (LOD) was 0.0054 U mL-1. Moreover, the luminous intensity of Probe 1 increased gradually with increase in ß-gal activity. It could be observed under 254 nm UV irradiation by the naked eye. Furthermore, this method only required a small amount of sample (20 µL) and a short analytical time (30 min) for the detection of ß-gal activity with a low LOD. Probe 1 was successfully used to detect ß-gal activity in real fruit samples, and can be applied to the quantitative and qualitative detection of ß-gal activity.