A simple, new, and sensitive spectrophotometric technique for the determination of methyldopa was presented in this research article. The suggested technique includes reacting metoclopramide with NaNO2 in the presence of hydrochloric acid to produce diazonium salt, and then the drug methyldopa reacts with the diazonium salt to produce a yellow azo dye. The maximum wavelength of the dye was 458 nm. This method is effectively used for the determination of methyldopa in different pharmaceutical formulations. It has been found that there are no significant interactions between common excipients and pure methyldopa. The results were processed statistically, and compared with those obtained from officially approved methods, they were found to be reasonable.
The determination of captopril (CAP) using a new continuous flow injection analysis (CFIA) method was given in this work CAP in its pure state and some of its pharmaceutical preparations. The technique can be described as simple, fast, sensitive, easy to operate, and low-cost. The CAP reacted with ammonium ceric(IV) sulfate (ACS)2(NH4 )2SO4Ce(SO4)2. 3 H2O in an acidic medium and the reaction led to the formation of a white, slightly yellowish precipitate. The formed precipitate was studied using Ayah 6S×1-ST-2D Solar cell-CFI Analyzer, a through the reflection of accident light on the surfaces of the precipitate particles at (0-1800), expressed as the response
... Show MoreAmiodarone hydrochloride (AH) has been determined spectrophotometrically Using methyl orange (MO). In our previous researches MO was used for determination of Mexiletine Hydrochloride [1]. The method based on complexation between MO and AH. After shaking and diluting the complex solution with D.W, the pH was adjusted with NaOH and HCl to pH 3. The colored complex formed between AH and the reagent were transferred into separating funnels and extracted using 5.5ml CH2Cl2 and were shaken for (5 minutes). The extracted organic layer was used for preparation of the calibration curves for spectrophotometric measurements of AH at 434nm. The blanks were carried out in exactly the same way throughout the whole procedure.&n
... Show MoreThe present study describes employing zero-, 1st - and 2nd -order derivative spectrophotometric methods have been developed for determination of lorazepam (LORA) and clonazepam (CLON) in commercially available tablets. LORA was determined by means of 1st (D1), 2nd (D2) derivative spectrophotometric techniques using zero cross, peak height, and Peak area. D1 used for the determination of CLON by using zero cross and peak height while D2 (zero cross) was used for the determination of CLON. The method was established to be linear in concentration containing different ratios of LORA and CLON range of (20-200 mg/L) and (5-35 mg/L) at wavelength range (250 -370 nm), (210-370nm) respectively. The proposed techniques are highly sensitive, precise a
... Show MoreVerapamil Hydrochloride (VH) has been determined spectrophotometrically by using Methyl Orange (MO). In our previous researches MO was used for determination of Mexiletine Hydrochloride [1]. The method was based on complexation between (MO and VH). After shaking and diluting the complex solution with D.W, the pH was adjusted with NaOH and HCl to pH 4. The colored complex formed between VH and the reagents were transferred into separating funnels and extracted using 4.5 ml CH2Cl2 and were shaken for (4 minutes). The extracted organic layer was used for the preparation of the calibration curves for spectrophotometric measurements of VH at 437nm. The blanks were carried out in exactly the same way throughout the whol
... Show MoreTwo simple, sensitive, accurate and economic methods A and B have been developed for the quantitative estimation of vancomycin hydrochlorid (VHC) and its formulations using another two drug compounds as a coupling reagents.The proposed methods are based on a coupling reaction between VHC and diazotized procain (method A) or diazotized sulphacetamide sodium (method B) in alkaline medium to form intense yellow, water-soluble dyes that are very stable and have a maximum absorption at 447 and 439 nm for methods A and B respectively. Regression analysis of Beer’s law plots showed good correlation in the concentration ranges 1-28 and 1-45 μg ml-1 for methods A and B, respectively with a molar absorbtivity of 4.605×104 L mol-1cm-1 and 4.516
... Show MoreA simple, accurate, precise, rapid, economical and a high sensitive spectrophotometric method has been developed for the determination of tadalafil in pharmaceutical preparations and industrial wastewater samples, which shows a maximum absorbance at 204 nm in 1:1 ethanol-water. Beer's law was obeyed in the range of 1-7?g/ mL ,with molar absorptivity and Sandell ? s sensitivity of 0.783x105l/mol.cm and 4.97 ng/cm2respectively, relative standard deviation of the method was less than 1.7%, and accuracy (average recovery %) was 100 ± 0. 13. The limits of detection and quantitation are 0.18 and 0.54 µg .ml-1, respectively. The method was successfully applied to the determination of tadalafil in some pharmaceutical formulations
... Show MoreTwo simple, sensitive, accurate and economic methods A and B have been developed for the quantitative estimation of vancomycin hydrochlorid (VHC) and its formulations using another two drug compounds as a coupling reagents.The proposed methods are based on a coupling reaction between VHC and diazotized procain (method A) or diazotized sulphacetamide sodium (method B) in alkaline medium to form intense yellow, water-soluble dyes that are very stable and have a maximum absorption at 447 and 439 nm for methods A and B respectively. Regression analysis of Beer’s law plots showed good correlation in the concentration ranges 1-28 and 1-45 μg ml-1 for methods A and B, respectively with a molar absorbtivity of 4.605×104 L mol-1cm-1 and 4.516
... Show MoreA new, simple, rapid and sensitive spectrophotometric method for the determination of sulfamethoxazole in both pure form and pharmaceutical preparations has been reported.The adapted technique based on utilization 4-aminobenzene sulfonic acid as a new modern chromogenic through an oxidative coupling reaction with sulfamethoxazole and potassium iodate in basic media to form orange soluble dye product with absorption maxima at 490 nm. Subject to Beer's law in the range 2–32μg mL-1. The values of molarabsorption coefficient (ε) and correlation coefficient were found to be 9.118 × 103 and0.9999 respectively whereas the Sandels index was
... Show MoreIn this study, the development of an indirect spectrophotometric method for the determination of folic acid in pure and pharmaceutical preparations is described. The method is based on the oxidation of pyrocatechol with iron (III) in an acidic medium, followed by the reaction with folic acid (FA) to produce a stable, water-soluble orange compound with maximum absorption at 350 nm versus the blank reagent. The complex of charge transfer was studied under optimal conditions; the titration graph was linear over the range of 0.5-25 μg/mL with a relative error of 1.2-2.8 and a relative standard deviation of 2.43-1.45 depending on the concentration level.