A thiomorpholine substituted malonyl-coumarin dye for discriminative detection of hydrazine and strong acidity.

Detection of toxic hydrazine and harmful strong acidity is of great importance for survival of organisms. In the present paper, a new thiomorpholine substituted malonyl-coumarin dye was synthesized for discriminative detection of hydrazine and strong acidity. At pH 7.4, the fluorescence at 560 nm decreased and that at 496 nm increased upon reaction with hydrazine, which was used for on-site detection of hydrazine vapor and endogenous hydrazine in live cells. From pH 2.0 to 1.2, the fluorescence at 563 nm increased greatly, which could be ascribed to the PET process from thiomorpholine to malonyl-coumarin. The probe was desirable for discriminative detection of toxic hydrazine and strong acidity.

The preparation of new covalent organic framework embedded with silver nanoparticles and its applications in degradation of organic pollutants from waste water.

A covalent organic framework (COF) featuring a unique light porous structure and silver nanoparticles shows high efficiency in the degradation of environmental pollutants. However, the combination of a COF with silver nanoparticles has never been reported until now. Toward this end, 2,4,6-tris-(4-formylphenoxy)-1,3,5-triazine (TPT-CHO) and hydrazine hydrate were selected as the construction units of the COF material (TPHH-COF), which possesses rich nitrogen and oxygen sites. Then a new type of composite catalyst (Ag@TPHH-COF) was successfully obtained by solution infiltration. The obtained materials were also fully characterized by standard methods. The results showed that the silver nanoparticles (with diameters of 5 ± 3 nm) were uniformly dispersed on the surface and in the interlayer gaps of the TPHH-COF substrate. Catalytic studies showed that Ag@TPHH-COF could catalyze the reduction of the various nitroaromatic compounds (NACs) with high efficiency, such as 4-nitrophenol, 2-nitrophenol, 4-nitroaniline, nitrobenzene, 4-nitrotoluene and 1-butyl-4-nitrobenzene. Ag@TPHH-COF could also catalyze the reduction of organic dyes such as Rhodamine B (RhB), Methylene Blue (MB), Methyl Orange (MO) and Congo Red (CR). Moreover, Ag@TPHH-COF has good reusability and high recovery.

A new triazine-based covalent organic polymer for efficient photodegradation of both acidic and basic dyes under visible light.

A new triazine-based covalent organic polymer (named COP-NT), which showed high catalytic activities for the degradation of acidic and basic dyes, is synthesized. Its structure characteristics were fully investigated, which featured large specific surface area, homogeneous porosity, strong visible light absorption, excellent thermal stability and semiconductor performance. The as-prepared COP-NT exhibits good chemical stability both in acidic and alkaline aqueous solutions, which could be used as an efficient photocatalyst for the degradation of methyl orange (MO), rhodamine B (RhB) and methylene blue (MB). The Ea values for the degradation of MO, RhB or MB are 9.40 kJ mol-1, 30.94 kJ mol-1 or 17.54 kJ mol-1, respectively. Furthermore, COP-NT showed excellent reusability in degrading all the above dyes without obvious performance decay.

A new fluorescent probe for colorimetric and ratiometric detection of sulfur dioxide derivatives in liver cancer cells.

A new ratiometric fluorescent probe was constructed with hemicyanine and 7-nitrobenzofurazan for detection of sulfur dioxide derivatives (HSO3-/SO32-). The ratiometric response mode could be attributed to the efficient FRET (Förster resonance energy transfer) platform. The probe exbihited some desirable properties including fast response (within 2 minutes), good selectivity and high sensitivity. Moreover, the probe could detect endogenous HSO3- in liver cancer cells rather than normal liver cells, implying the diagnosal potential of the probe.

Fluorescence detection of endogenous bisulfite in liver cancer cells using an effective ESIPT enhanced FRET platform.

Probe L-HF1, which featured large (pseudo) Stokes shifts and high FRET efficiency, was designed on a new ESIPT enhanced FRET platform for the detection of HSO3-/SO32-. L-HF1 could detect endogenous bisulfite in HepG2 cells but not in L-02 cells, implying the different bisulfite levels in normal and cancer cells of liver.

A mitochondria-targeted fluorescent probe for ratiometric detection of endogenous sulfur dioxide derivatives in cancer cells.

A new mitochondria-targeted fluorescent probe HCy-D, constructed by dansyl and hemicyanine fluorophores, for SO2 derivatives (HSO3(-)/SO3(2-)) was presented. This probe was designed based on a new FRET platform. HCy-D showed a ratiometric, sensitive and rapid response to HSO3(-)/SO3(2-). Importantly, HCy-D was successfully used for fluorescence imaging of endogenous bisulfite in HepG2 cells, which may benefit cancer diagnosis by discriminating liver cancer cells from normal liver cells.

Probing the symmetries of the Dirac Hamiltonian with axially deformed scalar and vector potentials by similarity renormalization group.

Symmetry is an important and basic topic in physics. The similarity renormalization group theory provides a novel view to study the symmetries hidden in the Dirac Hamiltonian, especially for the deformed system. Based on the similarity renormalization group theory, the contributions from the nonrelativistic term, the spin-orbit term, the dynamical term, the relativistic modification of kinetic energy, and the Darwin term are self-consistently extracted from a general Dirac Hamiltonian and, hence, we get an accurate description for their dependence on the deformation. Taking an axially deformed nucleus as an example, we find that the self-consistent description of the nonrelativistic term, spin-orbit term, and dynamical term is crucial for understanding the relativistic symmetries and their breaking in a deformed nuclear system.

Improving the anti-tumor effect of genistein with a biocompatible superparamagnetic drug delivery system.

The practical application of genistein as a low toxicity chemotherapeutic drug is hindered by many of its in vivo properties. To overcome these obstacles, a new multifunctional drug delivery system is developed, which is based on covalently attaching genistein onto Fe3O4 nanoparticles coated by cross-linked carboxymethylated chitosan (CMCH). The structure of the Fe3O4-CMCH-genistein nano-conjugate was confirmed by transmission electron micrographs (TEM), X-ray diffraction (XRD) and Fourier-transfer infrared (FT-IR) spectroscopy. The nano-conjugate shows good water solubility and superparamagnetic properties with a saturation magnetization of 55.1 emu/g. The effects of free genistein and FeO4-CMCH-genistein nano-conjugate on the proliferation and apoptosis of gastric cancer cell line SGC-7901 were investigated by MTT assay and flow cytometry (FACS). MTT results indicate that the Fe3O4-CMCH-genistein nano-conjugate exhibits a significantly enhanced inhibition effect to the SGC-7901 cancer cells than the free genistein. FACS data suggests that the inhibition on cell proliferation of the nano-conjugate is related with an induced apoptosis process. This drug delivery system is promising for future multifunctional chemotherapeutic application that combines drug release and magnetic hyperthermia therapy.