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The addition of a surfactant is a constructive strategy to enhance the deposition of pesticides on plant leaves in agriculture. However, currently used surfactants normally require to be used at high concentrations, and most of them are anionic or nonionic. In this work, we found that didecyldimethylammonium bromide (DDAB), a double-chain cationic surfactant, can not only inhibit droplets from receding and rebounding but also promote sufficient spreading on paraffin and Chenopodium album L. leaf surfaces at an ultralow concentration (0.05%), in comparison with widely reported sodium dodecyl sulfate (SDS) and bis(2-ethylhexyl)sulfosuccinate (AOT). This phenomenon is attributed to the fast adsorption kinetics of DDAB from the bulk to the newly created interface (mere 100 ms), decreasing the surface tension significantly. Field experiments further prove that the addition of DDAB can significantly improve the control efficiency of herbicides. Our findings provide a simple and effective way for improving the droplet deposition on hydrophobic plant surfaces, which may lead to economic and environmental benefits in the future.

In this work, by taking full advantage of the transformation of nitro group into amino moiety under the direct reduction of CO, a new metal-free colorimetric and near-infrared fluorescent probe NIR-CO for rapid and specific tracing of intracellular CO has been constructed, and it also become the first reaction-based near-infrared fluorescent probe for CO detection without additional reagents. Probe NIR-CO could quantitatively detect CO at the nanomolar level and the detection limit was calculated as low as 6.1 nM. Additionally, probe NIR-CO with preeminent sensing properties was successfully applied to monitor the fluctuations of endogenous CO levels in living systems. In particular, the up-regulation of heme oxygenase-1 (HO-1) caused by transient glucose deprivation (TGD) in living cells and the down-regulation of HO-1 inhibited by high glucose (HG) in zebrafish were confirmed for the first time via mapping the glucose-induced fluctuations of CO levels. Thus, we anticipate that probe NIR-CO not only can serve as a powerful tool to investigate the detailed biological functions of CO in the pathophysiological processes, but also possesses potential applications of in situ monitoring HO-1 activity in the complex biological systems.

Cell-selective imaging of some biological species is significant for the diseases research of a specific tissue or organ. Peroxynitrite (ONOO−) as a kind of reactive nitrogen species (RNS), plays extremely important roles in diverse physiological and pathological processes. Developing cell-specific fluorescent probes for tracing ONOO− in living systems remains a great challenge due to the complexity of internal environment and high autofluorescence. In this work, we developed a galactose-appended hepatoma-specific fluorescent probe Gal-NHP with hydroxynaphthalimide as the fluorophore and hydroquinone moiety as the responsive receptor for sensitively detecting endogenous ONOO− in live HepG2 cells. Probe Gal-NHP could selectively trace ONOO− without interference from other species such as HOCl and H2O2. In addition, the introduction of galactose enhanced the water solubility of this probe, and Gal-NHP could respond quickly to ONOO− in aqueous solution. The quantitative experiment showed the excellent sensitivity of this probe with a good linear relationship. Above all, fluorescence imaging results displayed it possessed excellent hepatoma-specific ability and could successfully detect endogenous ONOO− of hepatoma cells in real time. Thus, this newly developed probe would benefit to reveal the roles of ONOO− in hepatoma cells.

A water-soluble fluorescent probe for monitoring thiophenols based on a GFP-type TPC-OH fluorophore and a 2,4-dinitrophenyl ether recognition unit was designed. This probe possessed remarkable sensitivity and specificity toward thiophenols in an almost pure aqueous solution, and also showed good interference immunity to other related analytes including aliphatic mercaptans. Meanwhile, the probe displayed a prominent linear correlation between the thiophenol concentrations in the range of 0 to 20 μM and the fluorescence intensities at 492 nm, and the detection limit was as low as 33 nM. More strikingly, probe 1 was employed to visualize thiophenol in both living cells and zebrafish, which further demonstrated that probe 1 was a powerful practical tool in monitoring thiophenols in living systems.

Despite small-molecule surfactants and polymers being widely used as pesticide adjuvants to inhibit droplet bouncing and splashing, they still have intrinsic drawbacks either in the easy wind drift and evaporation, the unfavorable wettability, or the usage of nonrenewable resources. In this paper, we found that upon droplet impacting, 1D nanofibers assembled from natural glycyrrhizic acid (GL) could pin on the rough hydrophobic surface and delay the retraction rate of droplets effectively. Using GL as a tank-mixed adjuvant, the efficiency of glyphosate to control the weed growth was improved significantly in the field experiment, which addressed the dilemmas of current adjuvants elegantly. Our work not only provides a constructive way to overcome droplet bouncing but also prompted us to verify in future if all 1D nanofibers assembled from different small molecules can display similar control efficiencies.

As the applications of supramolecular assemblies are ultimately inscribed in their nanostructures, strategies that can precisely fabricate and regulate supramolecular architectures from small molecules are of great importance. Herein, in this research multiple modulations of supramolecular assembled structures of a natural triterpenoid-tailored bipyridinium amphiphile, 1-[2-(methyl glycyrrhetate)-2-oxoethyl]-[4,4']bipyridinium bromide (MGBP), have been achieved by adjusting solvents or counterions. Depending on the polarity of solvents, MGBP assembled into nanofibers, helices, pentagon and hexagon microsheets, respectively. Moreover, the nanofibers in methanol/water can transform into ribbons, robust fibers and fiber bundles by addition of counterions with different ionic sizes and valences. This work presents a simple and feasible methodology to modulate assembly structures of a natural triterpenoid-based amphiphile, which may expand the application of natural products in supramolecular materials.

Developing highly specific and ultrasensitive techniques for monitoring hypochlorous acid (HOCl) in the environment and living systems is very important to guarantee its safe use and disclose its diverse biological functions. We herein presented a simple water-soluble lysosome-targeted fluorescent probe TCRH for the detection of HOCl. Probe TCRH could sensitively monitor HOCl at the nanomolar levels with the detection limit of 0.12 nM. Additionally, probe TCRH with the response unit of thiocarbamate could selectively detect HOCl over other various analytes. Furthermore, probe TCRH showed an ultrafast response for HOCl (

Retention, a crucial process in pesticide spraying, is closely related to pesticide utilization efficiency and severely impacted by both low surface energy components and micro/nanostructures of foliage. To date, many pesticide carriers have been designed based on either foliar components or structures to enhance pesticide retention. However, as far as we know, there have been no reports taking these two factors into account simultaneously. Herein, we present a novel strategy to address this issue by taking advantage of both non-covalent interactions and topology effect between pesticide carriers and crop leaves. By grafting adhesive catechol-containing polymers onto the surface of hat-shape carriers (HSCs) via a one-step esterification reaction, a series of pesticide-loaded catechol functionalized hat shape carriers (pesticide-loaded Cat-HSCs) with high loading capacity were successfully prepared. Upon spraying on rice and wheat leaves, these functionalized carriers could target both the micropapillae and nanosplinters on foliage driven by the “hanger-hat” topology effect and non-covalent interactions, resulting in great improvement of foliar affinity, pesticide retention, and flush resistance. Moreover, pesticide-loaded Cat-HSCs possess a 15-day sustained-release property and satisfactory efficacy in controlling wheat powdery mildew. Overall, our resource-saving pesticide carrier provides an effective strategy for prolonging pesticide retention and reducing pesticide loss in agro-production.

Exploring techniques for monitoring the intracellular signaling molecule carbon monoxide (CO) in biosystems is important to help understand its various cellular functions. Therefore, a simple long-wavelength colorimetric fluorescent probe LW-CO was designed for selectively and sensitively detecting intracellular CO in living systems. Probe LW-CO is ultrasensitive and can track CO levels in the range of 0–1 μM, with a detection limit of about 3.2 nM. Additionally, the obvious color changes of probe LW-CO with CO (yellow to pink) provide a convenient way for on-site detection of CO with the naked eye. Probe LW-CO was applied to track the exogenous levels of CO in RAW264.7 cells. Probe LW-CO proved to be an efficient method for investigating various cellular functions of CO.

Liver cancer is a kind of high mortality cancer due to the difficulty of early diagnosis. And according to the reports, the concentration of reactive oxygen species (ROS) was higher in cancer cells than normal cells. Therefore, developing an effective fluorescent probe for hepatoma-selective imaging of hypochlorous acid (HOCl) which is one of the vital ROS is of great importance for understanding the role of HOCl in liver cancer pathogenesis. However, the cell-selective fluorescent probe still remains a difficult task among current reports. Herein, a galactose-appended naphthalimide (Gal-NPA) with p-aminophenylether as a new receptor and galactose moiety as hepatoma targeting unit was synthesized and employed to detect endogenous HOCl in living HepG2 cells. This probe was proved to possess good water solubility and could respond specifically to HOCl. In addition, probe Gal-NPA could completely react to HOCl within 3 s meanwhile accompanied by tremendous fluorescence enhancement. The quantitative linear range between fluorescence intensities and the HOCl concentrations was 0 to 1 μM (detection limit = 0.46 nM). More importantly, fluorescence confocal imaging experiments showed that probe Gal-NPA could discriminate hepatoma cells over other cancer cells and simultaneously trace endogenous HOCl levels in living HepG2 cells. And we thus anticipate that probe Gal-NPA has the potential application for revealing the functions of HOCl in hepatoma cells.

Mercury, as a highly toxic heavy metal, can cause very serious harm to human health and even death in severe cases. Therefore, we synthesized a novel ratiometric fluorescent probe for detecting mercury ions, with mercaptoethanol as the recognition receptor. Probe CMER could determine mercury ions in 0–1.6 μM and the detection limit is 7.6 nM. Moreover, CMER manifested a fast response for Hg2+ (within 5 s) and simultaneously observed that the color changed from light yellow to orange by naked eye. In addition to these preeminent spectral properties, the probe also had satisfactory bioimaging results in RAW 264.7 macrophage cells and zebrafish.

Peroxynitrite, one of the well-known reactive nitrogen species (RNS), which is considered to be an important oxidant. Besides, peroxynitrite plays an important role in the broad spectrum of biological processes, and it is also a vital participant in the emergence of cancer. To this end, the fluorescent probe PN-1 was rationally synthesized, which contains a coumarin-fused coumarin dye and borates as the specific recognition group. Probe PN-1 exhibits several obvious performances, for instance, high specificity, excellent sensitivity, and it could promptly respond toward ONOO−. Using this simple fluorescent probe, we achieved the imaging of endogenous and exogenous ONOO− fluctuations in living cells and zebrafish. Moreover, PN-1 has efficiently differentiated cancerous cells from normal cells owing to image their different native ONOO− levels, these results indicated that PN-1 is expected to be an analytical tool, for researching ONOO− related cancer biology and studying the related effect of ONOO− in food.

A facile method to synthesize novel monodispersed SnO2@N-doped carbon hollow nanoclusters as a high-performance anode material for lithium-ion batteries was explored. The uniqueness of this structure results from the large amount of ultrafine small SnO2 nanoparticles, the hollow interior space, and the continuous N-doped carbon shells, which successfully buffer problems associated with huge volume changes and guarantee electrical connectivity. All of these features make the nanocomposite well fitted for lithium storage. As a result, the electrochemical performance of monodispersed SnO2@N-doped carbon hollow nanoclusters as an anode in lithium-ion batteries is significantly improved, as it shows high initial discharge and charge capacities of 1572 and 1003 mA h g–1, respectively. Importantly, nearly 100 % discharge/charge efficiency is maintained during 100 consecutive cycles with a specific capacity above 910 mA h g–1.

A facile, reproducible, and scalable method was explored to construct uniform Au@poly(acrylic acid) (PAA) Janus nanoparticles (JNPs). The as-prepared JNPs were used as templates to preferentially grow a mesoporous silica (mSiO2 ) shell and Au branches separately modified with methoxy-poly(ethylene glycol)-thiol (PEG) to improve their stability, and lactobionic acid (LA) for tumor-specific targeting. The obtained octopus-type PEG-Au-PAA/mSiO2 -LA Janus NPs (PEG-OJNP-LA) possess pH and NIR dual-responsive release properties. Moreover, DOX-loaded PEG-OJNP-LA, upon 808 nm NIR light irradiation, exhibit obviously higher toxicity at the cellular and animal levels compared with chemotherapy or photothermal therapy alone, indicating the PEG-OJNP-LA could be utilized as a multifunctional nanoplatform for in vitro and in vivo actively-targeted and chemo-photothermal cancer therapy.

Hypobromous acid is an important reactive oxygen species (ROS), which is involved in operating various cellular functions. However, the abnormal production of HOBr can induce the generation of a variety of diseases. Although fluorescence probes are huge contributor to our understanding of the biological roles of HOBr, relatively few probes have been used to detect HOBr. Hence, we constructed a ratiometric fluorescent probe Ratio-HOBr with high selectivity to sensitively monitor HOBr. Probe Ratio-HOBr exhibited quick response (

It is very important to determine mercury owing to its complex biological poisonousness that could cause various physical diseases and even death. In this study, we designed a novel coumarin-based ratiometric fluorescent probe, CR-Hg, with DL-dithiothreitol moiety as the recognition receptor to detect mercury ions (Hg2+). CR-Hg could realize the quantitative detection of Hg2+ between 0 and 1.4 μM with low detection limit (1.6 nM). Furthermore, CR-Hg could react quickly with Hg2+ in a few seconds and accompanied by color changes from pale yellow to orange. In the end, the applications of CR-Hg in the water samples, living cells and zebrafish more deeply indicated that the probe could serve as a novel promising tool for revealing mercury distribution in the environment and organisms.

As one of the reactive oxygen species (ROS), hypochlorous acid (HOCl) plays a key role in the pathogenesis of a range of diseases. The detection of HOCl has been a hot research topic. Herein, this paper proposes a new conjugate of 4-hydroxy-1,8-naphthalimide and p-methylaminophenylether as fluorescent probe HNPE with simple synthesis and excellent performances to detect HOCl. The probe has a good linear relationship with HOCl (0–1 μM), and its detection limit is 6.56 nM. Moreover, this probe has good selectivity, which can distinguish HOCl from other common analytes. Importantly, the probe HNPE has some achievements in HOCl imaging of living cells and zebrafish. Hence, the probe HNPE is competent as a tool to visualize HOCl in biosystems.

In the appropriate Golgi stress response, adaptive repair will occur by changing or triggering the expression of related pathways. Furthermore, it also can inhibit the cytotoxicity of cells in the altered redox homeostasis. Elevated biosynthesis and transport of cysteine (Cys) will be induced to restore the abnormal redox state, and more evidences are needed to confirm this process in the Golgi stress response. Herein, we developed a novel Golgi-targetable Cys-specific fluorescent probe GT-Cys for sensitively detecting Cys generation during the Golgi stress response. In probe GT-Cys, thiobenzoate moiety was chosen as recognition group of Cys, and 4-CF3-7-aminoquinoline dye was selected as fluorophore and Golgi targetable unit. Probe GT-Cys can selectively and sensitively respond to Cys. Additionally, it has good targetable properties, facilitating the study of complicated stress response of Golgi apparatus. Importantly, the applications of probe GT-Cys in biological imaging showed that it is sensitive enough to basal Cys, especially to endogenous Cys during the Golgi stress response.

Iron plays an essential role in the chemical transformation of cells via the transition of multiple oxidation states of iron. Misregulation of iron may lead to the disorder of reactive oxygen species (ROS) catalyzed by iron, which is associated with diverse diseases. Therefore, the monitoring of labile iron in vivo is crucial for revealing its diverse functions in the biosystems. In this work, a novel “off-on” fluorescent probe NT-Fe was designed to detect ferrous ion (Fe2+) in both aqueous solutions and biological systems, based on the reduction of nitroxides to hydroxylamine. Probe NT-Fe manifested highly selective and sensitive detection (DL = 89 nM) of Fe2+. In addition, probe NT-Fe can detect Fe2+ within 50 s, which is conducive to real-time detection of labile iron in the biological system. Moreover, the intracellular Fe2+ can be tracked with probe NT-Fe in living cells effectively. Most of all, as far as we know, probe NT-Fe has been used for the first time to monitor Fe2+ in zebrafish.

CO-releasing molecule-2 (CORM-2), as a safe donor for releasing CO, has been widely adopted to disclose the physiopathological roles of CO and used as therapeutic drug replacing gaseous CO. The accurate determination of CORM-2 levels in biological systems is central for understanding its safe use as therapeutic agent and the cellular functions of CO. In this paper, a novel fluorescent probe CPD-NB was synthesized, which provided a safe and convenient way for detecting CORM-2 without the requirement of Pd2+ as an additional substrate. It featured a robust fluorescence response to CORM-2 with desirable sensitivity (the detection limit was as low as 4 nM), and showed high selectivity toward CORM-2 over other biologically relevant species. Moreover, with the low cytotoxicity of probe CPD-NB, the visualizations of CORM-2 changes in live cells and zebrafish were also achieved. Thus, we expected that probe CPD-NB could be as an ideal platform for safe and powerful imaging of CORM-2 in biological systems, and may thus promote the progress of CO-related research.

Hypobromous acid (HOBr) is profoundly implicated in many physiological and pathological conditions. In vivo, the production of HOBr is a double-edged sword for organisms. Appropriate amount of HOBr have effective antibacterial activity, however, abnormal production of HOBr can easily cause tissue damages. Unfortunately, the detailed cellular functions of HOBr are still unclear, which are mainly because highly specific and sensitive sensing of HOBr in living organism remains to be challenged. Based on that, a new n aphthalimide-derived 1-(2- a mino e thyl) p iperidine-containing highly selective fluorescent probe NAEP-HOBr for bioimaging endogenous HOBr was designed. Probe NAEP-HOBr possesses satisfactory sensitivity reflected in low detection limit (200 nM), pleasurable selectivity over others biological molecules, and rapid response for HOBr (∼1 min). Moreover, probe NAEP-HOBr is competent for tracking endogenous HOBr in living cells and zebrafish, which further provides an effective and powerful tool for tracking the fluctuations of endogenous HOBr in living organisms.

Developing a reliable tool for monitoring peroxynitrite (ONOO−) in the complex organisms is critical to uncover its detailed cellular functions in numerous physiological and pathological processes. Thus, a novel ratiometric fluorescent probe was reasonably designed for ONOO−, in which the rhodol-HBT conjugate dye was chosen as a fluorophore, and hydrazine moiety was adopted as recognition receptor of ONOO−. The probe exhibited outstanding sensitivity, specificity, and a fast response towards ONOO−. More importantly, the probe with a large emission shift (Δλem = 127 nm) has been proven to be capable of tracking ONOO− with high resolution in live cells and zebrafish. This work provides a simple and reliable tool for detecting and imaging ONOO− in the living systems, and thus we anticipate that the designed probe could be used as a powerful imaging tool in unraveling biological functions of ONOO−.

As a reactive nitrogen species (RNS), peroxynitrite (ONOO−) is known for its crucial functions in biological systems. Excessive formation of ONOO− is very closely related to the pathogenesis of a series of diseases, and thus, effective methods are needed for highly sensitive detection of ONOO−. Herein, a simple fluorescent probe RHHP-PN was proposed to detect ONOO−, and manifested obvious color changes from colorless to red in less than 10 s. Besides, it is not only suitable for quantitative detection of ONOO−, but also satisfactory in distinguishing ONOO− from other related species. What is particularly noteworthy is the fluorescence bioimaging for tracing endogenous and exogenous ONOO− in living cells and zebrafish. Therefore, probe RHHP-PN could be used as an imaging tool to visualize intracellular ONOO− in biological systems.

The accurate and sensitive determination of basal hypochlorous acid (HOCl) in the biosystems is critical for unraveling its various physiological and pathological functions. Additionally, recent studies have shown that cancer cells possess higher concentration HOCl than normal cells. However, related studies about the discrimation of tumor cells and tissues from normal cells and tissues by using a simple HOCl probe have seldom been reported. Herein, we presented a simple, water-soluble, two-photon long-wavelength fluorescent probe TPFR for detecting HOCl with outstanding selectivity over other potential interfering substances. The fluorescence titration experiments demonstrated that probe TPFR was capable of quantitatively detecting 0–500 nM HOCl (DL = 0.9 nM). Additionally, the rapid response (

Effective and rapid treatment of tularemia is needed to reduce morbidity and mortality of this potentially fatal infectious disease. The etiologic agent, Francisella tularensis, is a facultative intracellular bacterial pathogen which infects and multiplies to high numbers in macrophages. Nanotherapeutics are particularly promising for treatment of infectious diseases caused by intracellular pathogens, whose primary host cells are macrophages, because nanoparticles preferentially target and are avidly internalized by macrophages. A mesoporous silica nanoparticle (MSN) has been developed functionalized with disulfide snap-tops that has high drug loading and selectively releases drug intracellularly in response to the redox potential. These nanoparticles, when loaded with Hoechst fluorescent dye, release their cargo exclusively intracellularly and stain the nuclei of macrophages. The MSNs loaded with moxifloxacin kill F. tularensis in macrophages in a dose-dependent fashion. In a mouse model of lethal pneumonic tularemia, MSNs loaded with moxifloxacin prevent weight loss, illness, and death, markedly reduce the burden of F. tularensis in the lung, liver, and spleen, and are significantly more efficacious than an equivalent amount of free drug. An important proof-of-principle for the potential therapeutic use of a novel nanoparticle drug delivery platform for the treatment of infectious diseases is provided.