A sensitive and simple method for simultaneous preconcentration of trace heavy metal ions in some cerealand vegetable samples has been reported. The method is based on the adsorption of Cu2+, Fe3+, Zn2+ and Pb2+on 2-(2-nitro-phenylazo)-naphthalen-1-ol (NPN) loaded on activated carbon (AC). The adsorbed metals onactivated carbon were eluted using 3 ml 4 mol L−1 nitric acid. The influences of the...

A novel iridium(III) complex-based chemosensor bearing the 5,6-bis(salicylideneimino)-1,10-phenanthroline ligand receptor was developed, which exhibited a highly sensitive and selective color change from colorless to yellow and a visible turn-off luminescence response upon the addition of Cu(II) ions. The interactions of this iridium(III) complex with Cu2+ ions and thirteen other cations have b...

in this work, a novel hg2+ sensitive fluorescent chemosensor is constructed. the proposednano-chemosensor was prepared through the preparation of 3-(benzo[d]thiazol-2-yl)-7-hydroxy-2h-chromen-2-one functionalized silica nanoparticles which has high magnetization properties (btc-fe3o4@sio2). theûnal product was characterized by fourier transform infrared spectroscopy (ft-ir), thermal gravimetric...

We report herein a novel luminescent iridium(III) complex with two hydrophobic carbon chains as a non-reaction based chemosensor for the detection of Hg(2+) ions in aqueous solution (<0.002% of organic solvent attributed to the probe solution). Upon the addition of Hg(2+) ions, the emission intensity of the complex was significantly enhanced and this change could be monitored by the naked eye u...

In order to survive in an oxygen environment, aerobic organisms have developed numerous mechanisms to protect against oxygen radicals and singlet oxygen. One such mechanism, which appears to have attained particular significance during primate evolution, is the direct scavenging of oxygen radicals, singlet oxygen, oxo-haem oxidants and hydroperoxyl radicals by uric acid. In the present paper we...

Interaction of flavonoids with transition metals can be partially responsible for their impact on humans. Stoichiometry of the iron/copper complex with a flavonoid glycoside isoquercitrin, a frequent component of food supplements, was assessed using competitive and non-competitive methods in four (patho)physiologically-relevant pH values (4.5. 5.5, 6.8, and 7.5). Isoquercitrin chelated all test...

2014 57Fe Mössbauer spectroscopy has been combined with bulk magnetic measurements to determine the valence state and coordination of iron as well as the magnetic properties of the ternary oxide glasses, Li2O-B2O3Fe2O3. In all investigated glasses (~ 8.4 at % Fe), the Fe3+ ions coexist in tetrahedral and octahedral coordinations ; the presence of Fe2+ ions ( 15 %), which is observed in some gla...

The sensing of microcystin-LR (MC-LR) as a nonfluorescent species is still challenging since it has negligible influence on the emission fluorescent nanomaterials. Herein, well-defined “on–off–on” indirect chemosensing strategy developed by means nitrogen/phosphorus-codoped carbon dots (N/P CDs) for highly sensitive and selective MC-LR determination. nanoscale N/P CDs were conveniently synthesi...