Spectrophotometric Determination Methyldopa and Salbutamol by Oxidative Coupling, Cloud Point and Flow Injection in Pharmaceutical Formulations

2019 ◽  
Vol 9 (02) ◽  
Author(s):  
Nisreen Kais Abood ◽  
Mohammed Jasim M Hassan ◽  
Muneer A AL-Da,amy
Keyword(s):  
Cloud Point ◽  
Flow Injection ◽  
Oxidative Coupling ◽  
Cloud Point Extraction ◽  
Pharmaceutical Preparation ◽  
Active Material ◽  
Coupling Reaction ◽  
Molar Absorptivity ◽  
Simple Method ◽  
Oxidative Coupling Reaction

TThree methods study in this research simple, sensitive, an expensive and rapid Oxidative Coupling reaction, Cloud Point Extraction and Flow Injection spectrophotometric methods for determination Methyldopa and Salbutamol, the first method oxidative coupling reaction between the Methyldopa and thiosemicarbazide in presence of ferric nitrate anhydrous to yield dark green colored product that have absorbance at λ max 460 nm. Salbutamol coupling reaction with 4-nitrophenyl hydrazine in presence the potassium Iodide and sodium hydroxide to product the violet colored has absorbance at λ max 530 nm. Beer’s law is obeyed from (1-50) µg/ mL with sandall’s sensitivity (0.039,0.073), correlation coefficient (0.9998) and molar absorptivity (0.536×104,0.327×104) for Methyldopa and Salbutamol respectively. The secondly method to estimation the trace amount of phenolic drugs that product from the oxidative coupling reaction it is cloud point extraction, cloud point extraction enables the drugs to be precisely estimated under the optimal experimental conditions, the maximum absorption at λ max (470,535) nm respectively. The concentration was range (0.25-6) µg/mL, molar absorptivity 0.510×105 ,0.483×105 and enrichment factor (9.51,14.72) respectively for Methyldopa and Salbutamol.Flow injection analysis is simple method to determination the phenolic is based on the measurement of absorption signal for product resulting from oxidative coupling reaction , study all experimental parameters chemical and physical to development and stability the colored of product .Total flow injection of 1.5mL/min was pumped and active material was detect at λ max (460,530)nm respectively for Methyldopa and Salbutamol . In this the proposed methods were suxciffuly, applied to the determination Methyldopa and Salbutamol in pharmaceutical preparation.

scholarly journals Spectrophotometric Determination of Bisacodyl in Pure and Pharmaceutical Preparation via Oxidative Coupling Organic Reaction

2017 ◽  
Vol 14 (1) ◽  
pp. 181-188
Author(s):  
Baghdad Science Journal
Keyword(s):  
Oxidative Coupling ◽  
Pharmaceutical Preparation ◽  
Pharmaceutical Preparations ◽  
Coupling Reaction ◽  
Molar Absorptivity ◽  
Water Soluble ◽  
Alkaline Media ◽  
Oxidative Coupling Reaction ◽  
Relative Standard ◽  
Limit Of Quantitation

A simple, accurate and sensitive spectrophotometric way is used to determine Bisacodyl in pure and pharmaceutical preparations. The proposed method depends on using 2,4-Dinitrophenylhydrazine as chromogenic reagent . The method was based on the oxidative coupling reaction of Bisacodyl with 2,4-Dinitrophenylhydrazine with Sodium periodate in the presence of sodium hydroxide as alkaline media to form red water soluble dye product , that has a maximum absorption at ?max 522nm . Beer ,s law is obeyed in the concentration of (2.00–20.00) ?g.ml -1 .The molar absorptivity is (6505) L.mol-1.cm-1,a sandall sensitivity of(0.0555) ?g.cm-2), correlation coefficient of (0.9970) , Limitof detection (LOD) (0.0312 ?g.ml-1), limit of Quantitation (LOQ) (0. 3125 ?g.ml-1) and the relative standard deviation of RSD% (1.6). The method gave a successful determination for Bisacodyl in pharmaceutical preparations and the value of recovery % was better than (100.16%)

scholarly journals Spectrophotometric method for the determination of benzocaine by cerium ammonium sulphate with promethazine hydrochloride in pure and phar-maceuticals preparation

2019 ◽  
Vol 10 (2) ◽  
pp. 1420-1423 ◽  
Author(s):  
Amal H. Mhemeed
Keyword(s):  
Ammonium Sulphate ◽  
Spectrophotometric Method ◽  
Oxidative Coupling ◽  
Pharmaceutical Preparation ◽  
Coupling Reaction ◽  
Molar Absorptivity ◽  
Oxidative Coupling Reaction ◽  
Promethazine Hydrochloride ◽  
Cerium Ammonium

Easy, the accurate, sensitive spectrophotometric method used to determine Benzocaine in a pure and pharmaceutical preparation. The proposed method depends on using Promethazine hydrochloride as a reagent. Where it depends on oxidative coupling reaction of benzocaine by cerium ammonium sulphate with promethazine hydrochloride in the presence of hydrochloric acid to form green dye product, lmax 615 nm. Beers law is obeyed in the concentration of (5 –300 µg.ml-1). The molar absorptivity is (1.77 * 10 3) L.mol -1.cm-1, a sandal sensitivity of (0.0098) µq.cm-2 and RSD (± 0.56 %). The method gave a successful determination for benzocaine in a pharmaceutical preparation.

scholarly journals Indirect spectrophotometric Indirect spectrophotometric determination of chlordiazepoxide in pharmaceutical formulations via oxidative coupling reaction with phenothiazine

2018 ◽  
pp. 7-14
Author(s):  
Hind Hadi ◽  
Mariam Jamal
Keyword(s):  
Oxidative Coupling ◽  
Coupling Reaction ◽  
Pharmaceutical Formulations ◽  
Molar Absorptivity ◽  
Dosage Forms ◽  
Calibration Plot ◽  
Pharmaceutical Dosage Forms ◽  
Oxidative Coupling Reaction ◽  
Formed Product

Abstract A sensitive, precise and reliable indirect spectrophotometric method for the determination of chlordiazepoxide (CDE) in pure and pharmaceutical dosage forms is described. The method is based on oxidative coupling reaction between amino group resulting from acidic decomposition of CDE with phenothiazine in the presence of sodium periodate to produce an intense green soluble dye that is stable and shows a maximum absorption at 602 nm. The calibration plot indicates that Beer’s law is obeyed over the concentration range of 0.1?50 µg/mL, with a molar absorptivity of 1×104 L/mol cm and correlation coefficient of 0.9994.All the conditions that affecting on the stability and sensitivity of the formed product were studied and optimized and the suggested method was effectively applied for the determination of CDE in commercial dosage forms.

scholarly journals Spectrophotometric Methods for the Assay of Pyrilamine Maleate Using Chromogenic Reagents

2010 ◽  
Vol 7 (4) ◽  
pp. 1507-1513 ◽  
Author(s):  
V. Annapurna ◽  
G. Jyothi ◽  
V. Nagalakshmi ◽  
B. B. V. Sailaja
Keyword(s):  
Charge Transfer ◽  
Oxidative Coupling ◽  
Coupling Reaction ◽  
Pharmaceutical Formulations ◽  
Molar Absorptivity ◽  
Method Of Least Squares ◽  
Spectrophotometric Methods ◽  
Oxidative Coupling Reaction ◽  
Charge Transfer Complexation

Simple, accurate and reproducible UV spectrophotometric methods were established for the assay of pyrilamine maleate (PYRA) based on the formation of oxidative coupling and precipitation, charge transfer complexation products. Method A includes the oxidative coupling reaction of PYRA with 3-methyl-2-benzathiazolinone hydrazone (MBTH) in presence of Ce(IV). The formation of oxidative coupling product with 4-amino phenazone (4-AP) in presence of K3Fe(CN)6is incorporated in method B. Precipitation/charge transfer complex formation of the PYRA with tannic acid (TA)/Metol-Cr(VI) in method C were proposed. The optical characteristics such as Beers law limits, molar absorptivity and Sandell’s sensitivity for the methods (A-C) are given. Regression analysis using the method of least squares was made to evaluate the slope (b), intercept (a) and correlation coefficient (r) and standard error of estimation (Se) for each system. Determination of pyrilamine in bulk form and in pharmaceutical formulations were also incorporated.

scholarly journals A novel sensitive colorimetric determination of catecholamine drug in dosage form via oxidative coupling reaction with MBTH and potassium ferricyanide

2021 ◽  
Vol 5 (1) ◽  
pp. 51-58
Author(s):  
Safwan Ashour
Keyword(s):  
Oxidative Coupling ◽  
Colorimetric Method ◽  
Standard Free Energy ◽  
Coupling Reaction ◽  
Pharmaceutical Formulations ◽  
Molar Absorptivity ◽  
Potassium Ferricyanide ◽  
Colorimetric Determination ◽  
Oxidative Coupling Reaction

A new and direct colorimetric method has been established for the determination of catecholamine (methyldopa, MD) in both pure form and in pharmaceutical formulations. The method is based on the oxidative coupling reaction of MD with 3-methyl-2-benzothiazolinone hydrazone hydrochloride monohydrate (MBTH) and potassium ferricyanide at pH 10.4 in aqueous medium to form an orange product that has a maximum absorption at 460 nm. Beer's law plot showed good correlation in the concentration range of 1.0−56.0 µg mL-1, with detection limit of 0.31 µg mL-1. Molar absorptivity for the above method was found to be 6.56×103 L mol-1 cm-1. All the measurements were carried out at 25 ± 1.0 °C, the formation constant (logKf) value of colored species is 9.48 and the standard free energy (DG‡) is − 54.09 KJ mol-1. This method was applied successfully to determination of MD in tablets and the results were compared with the USP method. Common excipients used as additives in tablets do not interfere in the proposed method. The method is accurate, precise and highly reproducible, while being simple, cheap and less time consuming and hence can be suitably applied for routine analysis of MD in bulk and dosage forms.

scholarly journals Determination of Cefixime Using Batch, Cloud Point Extraction and Flow Injection as New Spectrophotometric Methods

2019 ◽  
Vol 30 (3) ◽  
pp. 28
Author(s):  
Nisreen Kais Abood ◽  
Mohammed Jasim M. Hassan ◽  
Muneer A. AL-Da'amy
Keyword(s):  
Bisphenol A ◽  
Cloud Point ◽  
Flow Injection ◽  
Cloud Point Extraction ◽  
Pharmaceutical Formulations ◽  
Sample Volume ◽  
Molar Absorptivity ◽  
Spectrophotometric Methods ◽  
Beer's Law ◽  
Beer’S Law

Three simple, sensitive, selective, accurate and efficient spectrophotometric methodsfor determining cefixime in bulk drug and pharmaceutical formulations havedescribed. The first method involved conversion of NH 2 in cefixime to diazoniumsalt, which has coupled with Bisphenol A in an alkaline medium. The orange coloredproduct showed λ max at 490 nm and followed Beer's law over a concentration range of1-50 μg mL -1 , with molar absorptivity of 0.866×10 4 L.mol -1 .cm -1 and the detectionlimit was 0.157 μg.mL -1 . The second method involved pre-concentration of a traceamount of cefixime-azo dyes using cloud point extraction (CPE). The extracted drug-dye was spectrophotometrically measured at λ max 500. The constructed calibrationcurve to determine cefixime followed Beer’s law in a range of 0.25-6 μg.mL -1 , with acorrelation coefficient of 0.9998, molar absorptivity of 0.961×10 5 L.mol -1 .cm -1 andthe detection limit was equal to 0.031 μg.mL -1 . The pre-concentration factor was 25and distribution coefficient (D) was 314.03.A diazotization of the studied drug (cefixime) and its coupling with Bisphenol A wasstudied using a developed flow injection analysis method, based on the detection ofthe absorption of the diazotization product. Chemical and physical properties [ofwhat??] were studied to develop the suggested method and to determine the stabilityof the colored of product. A flow rate of 2.5 mL.min -1 , 50 cm reaction coil and 100μL sample volume were used to operate the system and the orange colored productwas detected at 490 nm. The proposed three methods were successfully applied todetermine cefixime in pharmaceutical formulation, where results were satisfactory

Spectrophotometric determination of Drug Clonazepam in Pure form and Pharmaceutical Tablets by Oxidative Coupling Reaction with Chlorpromazine hydrochloride

2019 ◽  
Vol 10 (02) ◽  
Author(s):  
Nahlah Salman Saddam ◽  
K H Kadhim
Keyword(s):  
Oxidative Coupling ◽  
Coupling Reaction ◽  
Molar Absorptivity ◽  
Pure Form ◽  
Chlorpromazine Hydrochloride ◽  
Pharmaceutical Tablets ◽  
Spectrophotometric Methods ◽  
Oxidative Coupling Reaction ◽  
Quantification Limit

Sensitive, simple and a Precise spectrophotometric methods were development for the estimation reduced clonazepam (CZP) in purity form and in the pharmaceutical tablets from through using potassium bromate as oxidizing reagent for the drug and Chlorpromazine Hydrochloride (CPZ.HCL) as new chromogenic reagent. That led to forms colored products with a maximum absorbance of 530 nm. For the conditions reaction have been studied and optimized. The linearity range for Clonazepam was 0.05–3.5 μg/ ml, while the detections limit 0.0061 and the quantification limit 0.020 μg ml-1. The Molar Absorptivity 1.381×104 L/ mol cm with Shandell's sensitivity 0.0228 μg. cm-2. Finally the proposed methods were successfully Appling for estimation CZP in pure form and commercial formulations.

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