Absorbance Of Organic Phase Research Articles

Studies and analytical application of reaction of imipramine with chrome azurol S

Chrome azurol S (CAS) was tested as a spectrophotometric reagent for the determination of imipramine (IMP). It reacts in aqueous media with IMP forming pink–red, sparingly soluble in water ion association compound. This compound was quantitatively extracted with chloroform and the absorbance of organic phase was measured at 510 nm. The extraction conditions were studied using a batch method. On the basis of the results obtained with batch method, three-line flow-injection system was constructed. Batch and flow-injection methods were successfully applied for the determination of IMP in pharmaceutical preparation.

Ion-pair extraction of cadmium(II)-1,10-phenanthroline complex cation with tetraiodofluorescein.

In the presence of citrate ion, the ion-pair of cadmium (II)-1, 10-phenanthroline (phen) complex cation with tetraiodofluorescein (TIF) can be extracted into ethyl acetate from aqueous solution of 0.40.8 M NaOH. The extraction behavior was studied in order to apply to the spectrophotometric determination of cadmium(II). The extracted complex has a composition of [Cd(II)-(phen)2] (TIF). Its molar absorptivity at 543 nm is 1.38 × 105 dm3 mol-1 cm-1. Beer's low is held up to 5.6μg cadmium (II) in the 10ml of ethyl acetate. The recommended procedure is as follow : To a solution containing up to 5.6μg of cadmium (II) in a separatory funnel, 1 ml of 0.01 M phen, 1 ml of 0.3 M Na citrate, 3 ml of 5 M NaOH, and 1 ml of 1.5 × 10-3 M TIF added and the mixture is made up to 30 ml with water. After 5 min, the solution is shaken with 10 ml of ethyl acetate for 7 min. After two phases are separated with a centrifuge, the absorbance of organic phase is measured at 543 nm against the reagent blank. Zinc (II) seriously inteferes with the determination of cadmium (II).

Butanol extraction of copper-zincon complex with dibenzo-18-crown-6

The method is based on the extraction of ion-pair formed between copper-zincon anion and potassium-dibenzo-18-crown-6 cation (K-DBC-6). A sample containing (240) μg of copper was taken into a 100 ml separating funnel and diluted to 50 ml with water. After addition of 1 ml of zincon solution (0.12 %) and 2 ml of potassium citrate solution (10 %), the pH of the solution was adjusted to about 13 with a potassium hydroxide solution (2.5 M). The solution was then shaken with 20 ml of K-DBC-6 solution (0.1 %) in butanol for 2 min and allowed to stand for (23) min. The absorbance of organic phase was measured at 610 nm against butanol. In this method 93 % of the ion-pair of copper-zincon and K-DBC-6 can be extracted while the excess of zincon remaines in the aqueous phase. A linear calibration curve is obtained.