A Carbazole-based Fluorescent Probe with AIE Performance and a Large Stokes Shift for Peroxynitrite Detection and Imaging in Live Cells.

A carbazole-based fluorescent probe YCN with AIE performance and a large Stokes shift (242 nm) shift was synthesized by attaching 4-acetonitrile pyridine to the 3-phenylaldehyde butylcarbazole. Its structure was characterized by H NMR, C NMR and MS. Probe YCN has high selectivity and sensitivity toward ONOO.

Continuous Detection of Cobalt Ions and Pyrophosphates by NAC-CdTe Quantum Dots Fluorescence Probes.

In this work, a simple and sensitive N-acetyl-L-cysteine (NAC)-covered CdTe quantum dots (NAC-CdTe QDs) fluorescence probe for continuous detection of Co and pyrophosphate ions (PPi, PO) was synthesized. The fluorescence of the quantum dots was significantly quenched by Co through the coordination of Co and the carboxyl groups on the NAC-CdTe quantum dots. Interestingly, the combination of NAC-CdTe quantum dots with Co yields a new fluorescence probe of Co-modified NAC-CdTe QDs (Co@NAC-CdTe).

A Novel DNBS-based Fluorescent Probe for the Detection of HS in Cells and on Test Strips.

Hydrogen sulfide (HS) plays a key role in the physiology and pathology of organisms, and HS in the environment is easily absorbed and harmful to health. It is of great significance to develop a probe with good selectivity, high sensitivity and good stability that can detect hydrogen sulfide inside and outside organisms. In this work, we designed a novel "turn-on" fluorescent probe CIM-SDB for the detection of HS.

A novel fluorescent probe based on carbazole-thiophene for the recognition of hypochlorite and its applications.

A carbazole thiophene-aldehyde and 4-methylbenzenesulfonhydrazide conjugate CSH was synthesized by introducing 5-thiophene aldehyde at the 3-position of the carbazole group as the precursor and then condensing it with 4-methylbenzenesulfonhydrazide. CSH has high selectivity and sensitivity towards ClO, which can specifically identify ClO by UV-Vis and fluorescence spectroscopy. CSH can rapidly respond to ClO in the physiological pH range through a fluorescence quenching pattern, accompanied by the color of CSH changing markedly from turquoise to yellowish green under the 365 nm UV light.

A Novel L-Arginine Functionalized CdTe Quantum Dots Fluorescence Probe for Pyrophosphate Anion Detection.

In this paper, a novel amino acid surface-functionalized semiconductor CdTe quantum dot fluorescent probe amidated by carboxyl and amide groups was synthesized to detect pyrophosphate ions (PO, PPi). L-Arginine (L-Arg) was grafted onto cysteine modified CdTe quantum dots (Mea-CdTe QDs) to form a new L-Arginine-functionalized quantum dot fluorescent probe (L-Arg@Mea-CdTe). The prepared probe has good optical properties with multiple grafted functional groups on the surface.

A novel lipid droplets/lysosomes-targeting colorimetric and ratiometric fluorescent probe for Cu and its application.

A novel multifunctional fluorescent probe LL2 was prepared via a one-step condensation reaction between 3-formyl-N-butylcarbazole and 2-Hydroxy-1-naphthylhydrazone. LL2 can work as a colorimetric probe for Cu, and can also selectively recognize Cu via ratiometric fluorescence signal. After the addition of Cu, the probe LL2 responded rapidly within 5 s and reached stability within 30 s.

Construction of continuously enhanced fluorescent sensor for detection of glutathione in normal and cancer cells.

In this paper, water-soluble cysteamine (CA)-capping CdSe quantum dots (CA-CdSe) could be used as a continuous fluorescent sensor. The CA-CdSe QDs can respond to Ag with a detection limit of 54.1 nM.

A fluorescent probe based on triphenylamine with AIE and ICT characteristics for hydrazine detection.

A fluorescent probe MAM based on triphenylamine scaffold was synthesized. The electron donating group 4-methoxyphenyl and the electron acceptor dicyanoethylene were introduced on the triphenylamine scaffold to form a D-π-A fluorescent probe. The probe MAM exhibited the typical aggregation-induced emission (AIE) and intramolecular charge transfer (ICT) characteristics with the bright orange-red fluorescent emission in high water fraction (f ≥ 50%) and negligible emission in low water fraction.

Using an affinity analysis to identify phytoplankton associations.

Phytoplankton functional traits can represent particular environmental conditions in complex aquatic ecosystems. Categorizing phytoplankton species into functional groups is challenging and time-consuming, and requires high-level expertise in species autecology. In this study, we introduced an affinity analysis to aid the identification of candidate associations of phytoplankton from two data sets comprised of phytoplankton and environmental information.

Construction of Hybrid Fluorescent Sensor for Cu Detection Using Fluorescein-functionalized CdS Quantum Dots Via FRET.

A new hybrid fluorescent nanosensor (Flu@Mea-CdS) for the Cu detection in aqueous solution was constructed through fluorescence resonance energy transfer (FRET). The Flu@Mea-CdS was fabricated by amide linkage between CdS quantum dots capped with cysteamine (Mea-CdS) and fluorescein. With the formation of FRET process from Mea-CdS quantum dots to fluorescein, the fluorescence intensity of fluorescein at 520 nm was significantly enhanced.

A MADS-box transcription factor FoRlm1 regulates aerial hyphal growth, oxidative stress, cell wall biosynthesis and virulence in Fusarium oxysporum f. sp. cubense.

The fungal pathogen Fusarium oxysporum f. sp. cubense (Foc) causes Fusarium wilt that affects banana plants.

MPA-CdTe quantum dots as "on-off-on" sensitive fluorescence probe to detect ascorbic acid via redox reaction.

Mercaptopropionic acid (MPA) capped CdTe quantum dots (MPA-CdTe QDs) were synthesized in aqueous medium by hydrothermal method, which modified by Fe could be used as a fluorescent probe to detect ascorbic acid (AA). MPA-CdTe QDs fluorescence probe could be used as successive sensor for metal ions and AA with "on-off-on" process. The fluorescence of QDs was quenched after adding Fe to MPA-CdTe QDs.

AIE-active fluorescent polymeric nanoparticles about dextran derivative: preparation and bioimaging application.

Aggregation-induced emission (AIE), as a special phenomenon of fluorescence, can elegantly overcome the fluorescence quenching caused by common fluorescent materials under high concentration conditions and has attracted interest of researchers in many fields. Particularly AIE-active polymer nanoparticles have been widely utilized in a modern biomedical research. In this work, we prepared a novel kind of AIE-active fluorescent polymeric nanoparticals (Dex-OH-CHO) through a facile esterification between a new hydrophobic AIE-active 1, 8-naphthalimide derivative and the hydrophilic dextran.

Genome-Wide Identification of Calcium-Dependent Protein Kinases in and Functional Analyses in Nitrogen Deficiency-Induced Oil Accumulation.

Calcium-dependent protein kinases (CDPKs) are recognized as important calcium (Ca) sensors in signal transduction and play multiple roles in plant growth and developmental processes, as well as in response to various environmental stresses. However, little information is available about the CDPK family in the green microalga . In this study, 15 genes were identified in genome, and their functions in nitrogen (N) deficiency-induced oil accumulation were analyzed.

A RNA-Targeted Two-Photon Bioprobe with High Selective Permeability into Nuclear Pore Complexes for Dynamically Tracking the Autophagy Process among Multi-Organelles.

Dynamic tracking of the spatiotemporal coordination among various organelles to in-depth understanding of the mechanism of autophagy have attracted considerable attention. However, the monitor of nucleoli participation in autophagy was somehow neglected. Herein, we report a RNA-targeted bioprobe (ADAP) with high selective permeability into nuclear pore complexes, which induced a two-photon (TP) fluorescence "off-on" response by groove combination with RNA, dynamically monitoring the autophagy process among multiorganelles (nucleoli, mitochondria, and mitochondria-containing lysosomes).

A lipid droplet-targeted fluorescence probe for visualizing exogenous copper (II) based on LLCT and LMCT.

A simple and sensitive probe, pyridine-based Schiff base (PBSB), is prepared based on the previous studies, which shows a rapid response to copper (II) through a fluorescence enhancement process. On association with copper (II), PBSB immediately presents a large red-shift (130 nm) in emission spectrum simultaneously accompanying with increasing emission intensity. The mechanism and binding sites of PBSB detecting copper (II) have been established by theoretical calculations and HNMR study, respectively.

Exploration research on synthesis and application of a new dye containing di-2-picolyamine.

A newly designed fluorescence dye L based on di-2-picolyamine (DPA) moiety as a chelator was obtained under the protection of N at 120°C, and KI as catalyst with relatively better yield. More interestingly, L not only could selectively and sensitively detect Cu ions in aqueous medium but also examine the Cu ions of the actual water samples. Nevertheless, L could be visual in Hela cells with excellent cell permeability, viz, monitoring exogenous Cu ions as well as realizing an "on-off-on" process.

Rationally designed two-photon absorption compounds based on benzoxazole derivatives: structure-property relationships and bio-imaging applications.

A new series of benzoxazole-based two-photon absorption (2PA) chromophores (T1-5) were synthesized and fully characterized. Among them, T1-3 are linear donor (D)-π-acceptor (A) type fluorophores with various electron-donating groups, while T4 and T5 are multi-branched compounds stemming from T3. Their photophysical properties have been systematically investigated, and the two-photon absorption properties indicate that the highest 2PA cross-section (σ) is 2702 GM for T5 (in DMF).

A reversible and highly selective fluorescence "on-off-on" probe for detecting nickel ion in the mitochondria of living cells.

A simple molecular fluorescent probe L has been designed, synthesized and characterized. The probe upon interaction with different metals ions show high selectivity and sensitivity for Ni(2+) through fluorescence "turn-off" response in acetonitrile, and the fluorescence could be recovered when chelating agent TPEN is added in this system, viz an "on-off-on" process. Its recognition mechanism has been established by fluorescence spectra, (1)H NMR study.

Application and recognition behaviors of TPA-cored probes with subtle structural change.

Two new triphenylamine-cored probes (L1, L2) with different receptor units have been synthesized and fully characterized by IR, NMR and MS spectra. Their photophysical properties have been investigated in detail. The recognition abilities of two probes were evaluated by a series of metal ions, which showed that L1 could recognize Cu(2+) over other metal ions.

Synthesis, photophysical and electrochemical properties of two novel carbazole-based dye molecules.

Two carbazole-based dye molecules: 3-(6-benzothiazol-2-yl-9H-hexylcarbazole-3-yl)-2-cyano-acylic acid (D3) and 3-[5-(6-benzothiazol-2-yl-9H-hexylcarbazole-3-yl)-thiophen-2-yl]-2-cyan-acylic acid (D4) were synthesized by an approach from carbazole derivate using Vilsmeier-Haack, Suzuki cross-coupling and Knoevenagel reactions. Their physical and electrochemical properties were investigated. D3 and D4 exhibit different optical properties, such as UV absorption, photoluminescence, fluorescence quantum yield and fluorescence lifetime in different solvents.

Bis((E)-2-{5,5-di-methyl-3-[4-(1H-1,2,4-triazol-1-yl-κN (4))styr-yl]cyclo-hex-2-enyl-idene}malono-nitrile)-diiodido-mercury(II).

In the title complex, [HgI2(C21H19N5)2], the Hg(II) ion is located on a twofold rotation axis and is coordinated by two I atoms and two N atoms from two (E)-2-{5,5-di-methyl-3-[4-(1H-1,2,4-triazol-1-yl)styr-yl]cyclo-hex-2-enyl-idene}malono-nitrile ligands in a distorted tetra-hedral geometry. In the crystal, the mol-ecules are linked by inter-molecular π-π inter-actions between the triazole and benzene rings [centroid-centroid distance = 3.794 (3) Å] into a band extending in [010].

A new carbazole-based Schiff-base as fluorescent chemosensor for selective detection of Fe3+ and Cu2+.

A new carbazole-based Schiff-base (1) as a multi-functional fluorescent chemosensor was designed, synthesized and characterized, which can selectively recognized Fe(3+) and Cu(2+) ions over a number of other metal ions. Compound 1 could detect Fe(3+) and Cu(2+) by UV-Vis method and fluorescence method. The stoichiometry ratio of 1-Fe(3+) and 1-Cu(2+) are 2:1 and 1:1, respectively, by the method of Job's plot.

Investigation of optical nonlinearities and transient dynamics in a stilbenzene derivative.

The temporal properties of nonlinear absorption of a stilbenzene derivative have been investigated by time-resolved pump-probe techniques with picosecond laser pulses at the wavelength of 532 nm. With the help of an additional nanosecond and picosecond open-aperture Z-scan technique, numerical simulations based on a new five-energy level model are used to interpret the experimental results, and the nonlinear optical parameters of this new compound are determined. The five-energy level model is described by two-photon absorption (TPA) excited from ground-state-induced excited-state absorption (ESA) including singlet ESA and triplet ESA.