A rapid and sensitive method for the determination of amoxicillin trihydrate (AMXT) based on the diazo-coupling reaction was studied. Sulphanilic acid diazotizes with nitrite ion in acidic medium to produce a water soluble, colorless diazonium ion, which subsequently coupled with AMXT to form a colored azo dye in the alkaline medium, having maximum absorption at 455 nm. The calibration graph showed that Beer's law is obeyed over the concentration range of 0.3 – 30.0 μg/mL of AMXT, with the detection limit of 0.15 μg/mL and molar absorptivity was 2.3 × 104 L/mol.cm. The accuracy and the precision were acceptable depending upon the values of error percentage and relative standard deviation. The influence of common interfer

          Simple, cheap, sensitive, and accurate kinetic- spectrophotometric method has been developed for the determination of naringenin in pure and supplements formulations. The method is based on the formation of Prussian blue. The product dye exhibits a maximum absorbance at 707 nm. The calibration graph of naringenin was linear over the range 0.3 to 10 µg ml^-1 for the fixed time method (at 15 min) with a correlation coefficient (r) and percentage linearity (r²%) were of 0.9995 and 99.90 %, respectively, while the limit of detection LOD was 0.041 µg ml^-1. The method was successfully applied for the determination of naringenin in supplements with satisfac

Amiodarone 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

New, easy, simple, and fast spectral method for estimation of sulfamethoxazole (SMZ) in pure and pharmaceutical forms. The proposed method is based on the azotization of the drug compound by sodium nitrite in an acidic medium and then coupling with 2,3dimethyl phenol reagent (DMP) in a basic medium to yield an orange-coloured dye which shows λmax at 402 nm. Different affection of the optimization reaction has been completed, following the classical univariate sequence. The concentration of sulfamethoxazole about (1-15) μg. mL-1 with molar absorptivity of (14943.461) L.mol1 .cm-1 that obeyed Beer’s law. The detection and quantification limits were (0.852, 2.583) μg. mL-1 respectively, while the value of Sandell’s sensitivity (

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

A simple, fast, and sensitive spectrophotometric method was suggested for the determination of Bromhexine Hydrochloride (BHH) in its pharmaceutical formulations. The method depends on the diazotization of BHH by sodium nitrite in acidic medium to produce the corresponding diazonium salt. The latter is coupled with phloroglucinol reagent in alkali medium to form a yellow water soluble azo-dye which has a maximum absorption at 405 nm with a molar absorptivity of 2.7×10⁴ l.mol^-1.cm^-1 and Sandellʼs sensitivity of 0.01517 µg.cm^-1. Beerʼs low is obeyed within a concentration range of 0.25-15 µg.mL^-1 of BHH. The LOD and LOQ values of the proposed method were 0.087 µg.mL

Verapamil 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

     For the determination of metoclopramide hydrochloride (MCPD) in pharmaceutical formulations, a rapid and straightforward spectrophotometric method has been proposed. The method involves diazotizing the main amino group of MCPD with sodium nitrite followed by coupling reaction with reagent 1,7-Dihydroxynaphthalene (1,7-DHN) to form a stable and colored compound in alkaline medium of sodium hydroxide which showed a maximum absorbance‎ intensity at the wavelength 578 nm. The linearity of developed method has ranged from 1.0 - 15 ‎ µg.ml^-1‎‎ while the molar absorptivity 2.9867x10⁴ l.mol^-1.cm^-1, RSD% was less than 1.11%. While the LOD and LOQ were 0.059 ‎µg.ml^-1‎‎

Simple, sensitive and accurate two methods were described for the determination of terazosin. The spectrophotometric method (A) is based on measuring the spectral absorption of the ion-pair complex formed between terazosin with eosin Y in the acetate buffer medium pH 3 at 545 nm. Method (B) is based on the quantitative quenching effect of terazosin on the native fluorescence of Eosin Y at the pH 3. The quenching of the fluorescence of Eosin Y was measured at 556 nm after excitation at 345 nm. The two methods obeyed Beer’s law over the concentration ranges of 0.1-8 and 0.05-7 µg/mL for method A and B respectively. Both methods succeeded in the determination of terazosin in its tablets