Spectrophotometric Determination Of Valsartan In Pure Form And In Its Pharmaceutical Preparations

Abstract

An easy, rapid and economical spectrophotometric method for determination of Valsartan (Val), by reaction with 4-chloro-7-nitrobenzofurazan (NBD-Cl) as reagent in an alkaline interemediate. This method is based on the forming of product between (Val) and the chromogenic reagent (NBD-Cl), to produce a brown color at (pH 11.9) and λmax. 470 nm. Beer’s Law is obeyed at the concentrations range of (0.4-14.8 µg/ml), with molar absorptivity of (1.05×104 L/mol.cm) and correlation coefficient 0.9827, The limit of detection was 0.557 µg/ml. The suggested method was prosperity implement to the determination of (Val) in pure form and in its pharmaceutical formulations (tablets).

Preconcentration and Spectroscopic estimation of Zn (II) by sensitive Cloud Point Extraction Technique using Imidazole Azo Reagent

“…As for the FT-IR signals, the spectrum showed several bands: (A band at 3421.72 υ -1 belongs to the (N-H group, a band at 1680 υ -1 belongs to the (C=O group, and a band at 1597.06 υ -1 belongs to the (C=N group, and a band at 1575.84 υ -1 belongs to a group (N=N) show in Fig. 3 ) until formation cloud point layer, then separated this layer and dissolved in 5ml ethanol and measured the absorbance of alcoholic solution against blank prepared at the same manner in absence Zn 2+ ion at wave length of maximum absorbance for ion pair association complex extracted to CPL (, λ max ) 500 nm, on well on the aqueous phase treated according to Dithizone spectrophotometric method [14] and return to calibration care to determine the remainder quantity of Zn(II) ion in aqueous solution at extracted the subtraction this quantity from the original quantity of Zn(II)ion which is already in the aqueous solution to determine the transfer quantity of Zn 2+ ion to the CPL in order to formation an association complex afterward calculated distribution ratio [15,16,17,18] .…”

“…When extracting the Zn(II)using the cloud point technique (CPE), the presence of some positive ions in the aqueous solution had an effect on the extraction efficiency, which can be seen in the absorption values and distribution ratios D, and by observing the values of D for positive ions when extracting Zn(II)using the cloud point technique (CPE) has an effect on the extraction efficiency, as Ni +2 bon when it is ionized. In terms of the Cd 2+ ions in the As a result, the process of separating Zn(II)slows down, implying that it has a competitive impact in building a complex between the reagent and Zn(II)lowering the value of D and the separation ratio % E percent As for the rest of the ions They range in effect [15,[17][18][19]21,22,26]. To validate the potential structures of the isolated complexes, a continuous changes procedure was used, which included creating solutions with (1* 10 -4) M of organic reagents.…”