الفهرس | Only 14 pages are availabe for public view |
Abstract The aim of this work is to develop new spectrophotometric and potentiometric methods for the determination of micro amounts of different pharmaceutical compounds such as citalopram hydrobromide (CTP) and tadalafil (TDF) in pharmaceutical preparations and biological samples. The spectrophotometric methods in the present investigation include: ion-pair technique which is based on the formation of yellow ion-pair complexes between the basic nitrogen of the drug and four sulphonphthalein acid dyes, namely; bromocresol green (BCG), bromothymol blue (BTB) , bromocresol purple (BCP) and bromophenol blue (BPB) in acetate buffer. The formed complexes were extracted with chloroform, and oxidation-reduction technique which is based on the oxidation of the studied drugs by a known excess of potassium permanganate in acidic medium and estimation the unreacted permanganate with amaranth dye (AM), indigocarmine (Indigo) and methylene blue (MB). The proposed methods are successfully applied to determine the studied drugs in the pure and in their dosage forms. The results obtained are compared statistically by Student’s Hest (for accuracy) and variance ratio F-test (for precision) with the official methods at 95 % confidence level. The results showed that the t- and F- values are less than the critical tabulated value indicating that there is no significant difference between the proposed and official methods. Thus the proposed spectrophotometric and potentiometric methods can applied in routine analysis for determination of the studied drugs in pure and in dosage forms. |