A novel dual-responsive colorimetric/fluorescent probe for the detection of N2H4 and ClO- and its application in environmental analysis and bioimaging.

Hydrazine (N2H4) and hypochlorite (ClO-) are both reactive chemical substances extensively utilized across various industrial domains. Excessive hydrazine (N2H4) and hypochlorite (ClO-) can pose significant risks to the environment, ecosystems, and human health. In order to assess and control the environmental hazard caused by N2H4 and ClO-, there is an imperative need for efficient methods capable of rapid and precise detection of these contaminants. This paper introduces a novel dual-responsive colorimetric/fluorescent probe (MDT) for the detection of N2H4 and ClO- in environmental and biological samples. The probe exhibits turn-on fluorescent responses to N2H4 or ClO- with low detection limits (N2H4: 8 nM; ClO-: 15 nM), large Stokes shifts (N2H4: 175 nm; ClO-: 203 nm), short response time (N2H4: 4 min; ClO-: 5 s) and broad pH range (5-10). In practical applications, MDT has been successfully employed in detecting N2H4 and ClO- in water and soil samples from diverse locations. Test strips loaded with MDT offer a visual and convenient means to track N2H4 vapor and quantify N2H4 and ClO- concentrations in solutions. Finally, MDT has been utilized for sensing N2H4 and ClO- in Arabidopsis thaliana roots and living zebrafish. This study presents a promising tool for monitoring N2H4 and ClO- in the environment and living organisms.

Design, synthesis, antifungal evaluation and mechanism study of novel norbornene derivatives as potential laccase inhibitors.

BACKGROUND: To discover novel fungicide candidates, five series of novel norbornene hydrazide, bishydrazide, oxadiazole, carboxamide and acylthiourea derivatives (2a-2t, 3a-3f, 4a-4f, 5a-5f and 7a-7f) were designed, synthesized and assayed for their antifungal activity toward seven representative plant fungal pathogens. RESULTS: In the in vitro antifungal assay, some title norbornene derivatives presented good antifungal activity against Botryosphaeria dothidea, Sclerotinia sclerotiorum and Fusarium graminearum. Especially, compound 2b exhibited the best inhibitory activity toward B. dothidea with the median effective concentration (EC50) of 0.17 mg L-1, substantially stronger than those of the reference fungicides boscalid and carbendazim. The in vivo antifungal assay on apples revealed that 2b had significant curative and protective effects, both of which were superior to boscalid. In the preliminary antifungal mechanism study, 2b was able to injure the surface morphology of hyphae, destroy the cell membrane integrity and increase the intracellular reactive oxygen species (ROS) level of B. dothidea. In addition, 2b could considerably inhibit the laccase activity with the median inhibitory concentration (IC50) of 1.02 µM, much stronger than that of positive control cysteine (IC50 = 35.50 µM). The binding affinity and interaction mode of 2b with laccase were also confirmed by molecular docking. CONCLUSION: This study presented a promising lead compound for the study of novel laccase inhibitors as fungicidal agrochemicals, which demonstrate significant anti-B. dothidea activity and laccase inhibitory activity. © 2024 Society of Chemical Industry.