- 作者: Mir Ali Farajzadeh* and Sepideh Nagizadeh
- 作者服務機構: Department of Chemistry, Faculty of Science, Urmia University, Urmia, Iran
- 中文摘要: In this study, a dual wavelength spectrophotometric method was presented on the basis of Cu2+_NH3 complex decomposition by the citrate ion and the formation of Cu2+_citrate complex. Sum of the absorbance decreasing at 600 nm (lmax for Cu2+-NH3 complex) and the absorbance increasing at 750 nm (lmax for Cu2+-citrate complex) was used in quantification. This method is very selective, fast and inexpensive but relatively less sensitive. The calibration curve is linear in the range of 0.4-8 mmol/L with a detection limit of 0.13 mmol/L. The relative standard deviation (RSD%) for the six repeated determinations (2 mmol/L) is 1.75%. Interference studies of more than twenty common compounds, which are present in the studied samples, were carried out. Only oxalic and ascorbic acids are serious interferes and which interferences were eliminated by simple procedures. Finally, the proposed method was successfully applied in the determination of citric acid content in ORS powder and some fruit juices.
- 英文摘要: --
- 中文關鍵字: Ascorbic acid; Dual wavelength spectrophotometry; Pharmaceuticals; Fruit juices.
- 英文關鍵字: Ascorbic acid; Dual wavelength spectrophotometry; Pharmaceuticals; Fruit juices.