- Turkish Journal of Chemistry
- Vol: 27 Issue: 5
- Catalytic Spectrophotometric Determination of Manganese in Some Medicinal Plants and Their Infusions
Catalytic Spectrophotometric Determination of Manganese in Some Medicinal Plants and Their Infusions
Authors : Konstantin L. Mutaftchiev
Pages : 619-626
View : 13 | Download : 4
Publication Date : 9999-12-31
Article Type : Makaleler
Abstract :The catalytic effect of manganese (II) on the oxidation of the dye 1,3-Dimethyl- 2 [4-N (N,N-dimethylamino) phenylazo] imidazolium perchlorate (BR) with potassium periodate in the presence of 1,10-phenanthroline was investigated. The reaction was followed spectrophotometrically by measuring the decrease in the absorbance of the dye at 540 nm. Under optimum conditions (5 \times 10-5 mol dm-3 BR, 2 \times 10-4 mol dm-3 potassium periodate, 1 \times 10-4 mol dm-3 1,10-phenanthroline, 0.1 mol dm-3 buffer -- pH 3.0, 70 °C, 5 min) manganese (II) in the range 0.1--4.5 ng cm-3 can be determined by the fixed-time method with a detection limit of 0.03 ng cm-3. The developed method is highly sensitive, selective, and simple. The method was applied successfully to analyse infusions of some medicinal plants (common balm, creeping thyme, common lungwort, and colt's-foot) for trace amounts of total manganese and free manganese (II) ions without separation. The results showed good agreement with those obtained by atomic absorption spectrophotometry.Keywords : manganese determination, catalytic spectrophotometric method, medicinal plants, infusions