Near-infrared fluorescent gold nanoclusters (AuNCs) were prepared by sonochemical method and applied for the selective and sensitive detection of nitrite. The fluorescence of AuNCs could be selectively quenched by nitrite, and the mechanism was discussed in detail. The fluorescence intensity decreased linearly upon the increasing concentration of nitrite in a wide range of 2.0×10(-8) M to 5.0×1...

Background. There are no reported data to explain how Salmonella suppress nitrite ion production in macrophages or whether this phenomenon is unique to typhoidal or non-typhoidal serovars. The aims of this study were, therefore, to investigate these phenomena. Methods. We measured survival of S. typhimurium 14028 and its phoP mutant in murine J774 macrophages, cultured with or without interfero...

A rapid isocratic method of high performance liquid chromatography system (HPLC) with a glassy carbon working electrode of electrochemical detector is set up for quantitative detection of trace amount of nitrite ion (NO2) in aqueous protein containing cell lysate, cell media, plasma, serum, urine and other body fluids. The solid extraction reversed phase cartridges (Sep-pak) are used for deprot...

Water extract of respirable particulate matter (RPM) was analyzed by Ion chromatography technique to investigate the presence of nitrite (NO2) as secondary aerosol in ambient environment. The nitrite particulates undergo photo hydroxyl radical reaction in environment produce nitrous acid, which reacts with metal and absorbs on RPM as water-soluble metal salt. The mean concentration of nitrite w...

Knowledge of relative NH(4+)-N to NO(2-)-N oxidation and NO(2-)-N to NO(3-)-N oxidation dynamics is essential before application of either single-step or two-step nitrification models to fit batch nitrification respirograms. We have previously shown that two step nitrification models based on respirometry permit the estimation of kinetic parameters for both nitrification steps from a single res...

The 1.70 Å-resolution X-ray crystal structure of the green pigment occasionally present in nitrite-cured meat reveals a regiospecific nitration of the heme at the 2-vinyl position; the regiospecificity is favored on steric grounds, and results in movement of the 2-nitrovinyl moiety into the plane of the 24-atom heme macrocycle.

By JOHN D. HARLEY AND HELEN ROBIN T HE CHANGES which result when intact erythrocytes are exposed to the nitrite ion have been studied for almost a century.’6 Such exposure has been found to cause the oxidation of oxyhemoglobin to methemoglobin,26 and of reduced glutathione ( GSH ) to oxidized glutathione ( GSSG ) . .6 In addition, erythrocytes treated with nitrite have been widely used to inves...

A novel spectrophotometric reaction system was developed for the determination of nitrite as well as nitrate in water samples, and was applied to a flow-injection analysis (FIA). The spectrophotometric flow-injection system coupled with a copperised cadmium reductor column was proposed. The detection was based on the nitrosation reaction between nitrite ion and phloroglucinol (1,3,5-trihydroxyb...