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Updated: Jun 28, 2026

Quantifying the Binding Interactions Between Cu(II) and Peptide Residues in the Presence and Absence of Chromophores
Published on: April 5, 2022
Spectrophotometric determination of molybdenum based on charge transfer complexes sensitized by copper(II)
1Department of Chemistry, Suzhou University, Suzhou 215006, China.
Abstract:
A new high sensitive spectrophotometric determination of trace molybdenum was investigated. The sensitivity of the determination of molybdenum, which based on the color charge transfer complex of molybdotungstophosphate-3,3',5,5'-tetramethylbenzidine, was greatly enhanced by copper(II) ions in the presence of polyvinyl alcohol. The improved method maintained the features of simplicity, rapidity and selectivity, especially eliminating the interference from tungsten. Under the optimum conditions, Beer's law was obeyed over the range from 2 to 32 ng ml(-1) molybdenum with molar absorptivity being 4.92x10(5) l mol(-1) cm(-1) at 660 nm. The relative standard deviation was 1.2% under nine determinations for 16 ng ml(-1) Mo(VI). The present method had been applied to the determination of trace molybdenum in tungsten ores with satisfactory results.
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