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Chromium(iii) selective membrane sensors based on schiff bases as chelating ionophores. Author information (1)department of chemistry, indian institute of technology-roorkee, roorkee 247667, india. Sensitive and selective spectrofluorimetric determination of chromium(vi) in water by fluorescence enhancement. Author information (1)department of chemistry, tsinghua university, beijing 100084, pr china. Determination of chromium in sea water by atomic absorption spectrometry. Chromium(vi) concentrations may be arrived at by subtraction of the concentration of cr iii from total dissolved cr. A microfluidic paper-based analytical device for rapid quantification of particulate chromium. Chromium detection is of intense interest, as cr(vi) is highly toxic even at trace (low mg l 1) levels. Due to the strong oxidizing nature of cr(vi), exposure leads to health problems that include lung cancer, stomach cancer, nasal cancer, allergic dermatitis, and mutagenesis 1-5. Despite its known effects on human health cr(vi) species are found in many places including. Chromium(iii) is converted to its acetylacetone complex and extracted into mibk. Calibrate the method by refluxing 3 g of cliromium(iii) in 10 ml of solution with acetylacetone, and carry through the complete extraction procedure. The interaction of chromium (iii) with humic substances obtained from pond sediment was experimentally studied using electrophoresis combined with ultrafiltration. The results show that within the neutral ph range chromium (iii) in the presence of humic substances and some organic acids forms uncharged andor negatively charged organic complexes of various molecular weights. This paper presents an electrochemical sensor for cr(vi) (chromate ion) in water. A disposable screen-printed electrode was modified with gold nanostars (aunss) that were synthesized by goods buffer method. Linear sweep voltammetry (lsv) was employed for the detection of cr(vi) in 0. The aunss are shown to provide higher current response to cr(vi) than spherically. Chromium exists in environmental water and seawater in two different oxidation states, cr(iii) and cr(vi). Thermodynamic calculations predict that in oxygenated natural waters chromium should exist almost exclusively as cr.