Spectrophotometric Determination of p-aminobenzoic acid via Diazotization and Coupling reaction

2021 ◽  
pp. 5313-5318
Author(s):  
Rana S. Al-Saffar ◽  
Safaa A. Zakaria ◽  
Nabeel S. Othman
Keyword(s):  
Folic Acid ◽  
Hydrochloric Acid ◽  
Sodium Nitrite ◽  
Azo Dye ◽  
Coupling Reaction ◽  
Molar Absorptivity ◽  
Water Soluble ◽  
Good Sensitivity ◽  
Aminobenzoic Acid

A simple and accurate spectrophotometric method to assay p-aminobenzoic acid (PABA) has been suggested. The method based on the diazotization of PABA via reaction with nitrite ions which liberated in the medium through the reaction of sodium nitrite with hydrochloric acid, then coupling the dizotised-PABA(D-PABA)with 1-naphthylamine -7-sulphonic acid (1-NASA) to form an intense colored pink azo dye ,it is water-soluble , very stable and has a maximum absorbance at 525 nm. The absorbance was increase with the increasing of PABA amounts in the solution, and the linearity from 2.5 to70 µg in 10 ml (0.25to7 µg.ml-1).The molar absorptivity and Sandell ҆s sensitivity values have been calculated they equal to 3.6057x104 L.mol-1 cm -1 and 0.0037993 µg. cm-2 respectively. The two values above demonstrated a good sensitivity of the suggested method. The method has been used in estimated PABA resulted from analysis of folic acid in tablet.

Simultaneous Spectrophotometric Determination of Salbutamol by Coupling with Diazotized 4-Aminobenzoic acid

2017 ◽  
Vol 8 (1) ◽  
Author(s):  
Hind Hadi ◽  
Gufran Salim
Keyword(s):  
Pharmaceutical Preparations ◽  
Coupling Reaction ◽  
Dosage Forms ◽  
Water Soluble ◽  
Trace Determination ◽  
Aminobenzoic Acid ◽  
Optimum Conditions ◽  
Colored Product ◽  
Versus Concentration

A simple, rapid and sensitive spectrophotmetric method for trace determination of salbutamol (SAL) in aqueous solution and in pharmaceutical preparations is described. The method is based on the diazotization coupling reaction of the intended compound with 4-amino benzoic acid (ABA) in alkaline medium to form an intense orange, water soluble dye that is stable and shows maximum absorption at 410 nm. A graph of absorbance versus concentration indicates that Beer’s law is obeyed over the concentration range of 0.5-30 ppm, with a molar absorbtivity 3.76×104 L.mol-1 .cm-1 depending on the concentration of SAL. The optimum conditions and stability of the colored product have been investigated and the method was applied successfully to the determination of SAL in dosage forms.

scholarly journals Spectrophotometric Determination of Bromhexine Hydrochloride in Its Pharmaceutical Preparations by Diazotization and Coupling Method

2020 ◽  
pp. 2172-2181
Author(s):  
Saad Hasani Sultan ◽  
Zainab Walid Majed
Keyword(s):  
Azo Dye ◽  
Acidic Medium ◽  
Diazonium Salt ◽  
Pharmaceutical Preparations ◽  
Pharmaceutical Formulations ◽  
Molar Absorptivity ◽  
Water Soluble ◽  
Standard Methods ◽  
Alkali Medium

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-1 and 0.293 µg.ml-1, respectively. The proposed method was validated with standard methods and successfully applied to the determination of Bromhexine in its pharmaceutical formulations as tablets, syrup, and injections.

scholarly journals Spectrophotometric determination of metoclopramide medicine in bulk form and in pharmaceuticals using orcinol as reagent

2016 ◽  
Vol 29 (2) ◽  
pp. 85-91
Author(s):  
Hanaa Khazal Abdulghareeb Taha ◽  
Mohauman Mohammed Al-Rufaie ◽  
Zahraa Yosif Motaweq
Keyword(s):  
Coupling Reaction ◽  
Molar Absorptivity ◽  
Water Soluble ◽  
Azo Coupling ◽  
Average Recovery ◽  
Yellow Color ◽  
Relative Standard ◽  
Naoh Solution ◽  
Official Procedure

Abstract A modern, accurate, simple and sensitive spectrophotometric procedure is tested for the appreciation of metoclopramide medicine as perspicuous form, as well as in various kinds of pharmaceutical dosages. The procedure depends on the interaction of metoclopramide (MCP) medicine and orcinol reagent by utilizing azo coupling reaction. The orcinol in NaOH solution middle to give a latterly ligand which reacts with copper (II) to output the complex with strong yellow color at 50°C. The resulting complex is water soluble, stable and can be determined spectrophotometrically at wavelength 459 nm. The calibration curve absorbance vs. concentration was established in the concentration range 0.6-12 ppm, and the curve followed the Beer’s law in this range. The procedure precision is given by the average recovery of 99.91% sequentially, as well as by the average relative standard deviation 0.70%, related to the amount of drug. The sensitivity is established at molar absorptivity 1.9044×104 l‧cm-1‧mol-1. The Sandell sensitivity is tested as 0.002 μg/cm2. The analytical results for the tested procedure agree with the official procedure. The interferences from medicine additives were tested. The established procedure is successfully examined on the appreciation of MCP in diverse kinds of pharmaceuticals.

scholarly journals Spectrophtometric determination of Hydrochlorothiazaide by oxidative coupling with O-Phenylendiamine

2019 ◽  
Vol 24 (2) ◽  
pp. 46
Author(s):  
Rahma Abdul Hameed Hasan1 ◽  
Ali Ibraheem Khaleel2
Keyword(s):  
Oxidative Coupling ◽  
Coupling Reaction ◽  
Molar Absorptivity ◽  
Water Soluble ◽  
Sensitivity Index ◽  
Medium Ph ◽  
Oxidative Coupling Reaction ◽  
Stable Product ◽  
Orange Color

This study includes the development of a new sensitive spectrophotometric method for the determination of a hydrochlorothaizide in aqueous solution and pharmaceultical preparations. The method is based on the oxidative coupling reaction of hydrochlorothaizide with O-phenylendiamine reagent in a acidic medium pH 1.5 in the presence of potassium ferricyanide  to produce an intense orange color, water soluble and stable product , which exhibits maximum absorption at 450 nm. Beer’s law is obeyed over the concentration arange 6 to 48 µg.ml-1 of hydrochlorothaizide, with a molar absorptivity of  3602.17  L.mo1-1 .cm -1 , Sandell’s sensitivity index of 0.03 µg.cm-2 , relative error range not more than 0.215% , and D.L 0.0835µg.ml-1 . The method has been successfully applied for the determination of hydrochlorothaizide in tablets.   http://dx.doi.org/10.25130/tjps.24.2019.030

scholarly journals Spectrophotometric Determination of Trace Amount of Nitrite in Water with p-Nitroaniline and 1-Naphthol

2015 ◽  
Vol 19 (2) ◽  
pp. 89-93 ◽  
Author(s):  
Deba Bahadur Khadka ◽  
Laxmi Pachhai
Keyword(s):  
Waste Water ◽  
Hydrochloric Acid ◽  
Spectrophotometric Determination ◽  
Water Samples ◽  
Trace Amount ◽  
Azo Dye ◽  
Molar Absorptivity ◽  
Analytical Wavelength ◽  
Sensitive Method

A simple, selective and sensitive method for the spectrophotometric determination of nitrite in different natural and waste water samples is applied. Nitrite reacts with p-nitroaniline in the presence of hydrochloric acid to form diazonium cation which is subsequently coupled with 1-naphthol to form a stable azo dye. The ?max for the azo dye is found to be 610 nm. At analytical wavelength 610 nm the Lambert-Beer’s law obeys over the concentration range 0.035-0.123 ?g/ml of nitrite. The correlation coefficient, molar absorptivity and Sandell’s sensitivity of the method were found to be 0.99, 5.24×104 lit.mol-1cm-1 and 8.77×10-4?g cm-2 respectively. The percentage recovery was found to range from 93-109% and the interference of foreign ions was also studied.Journal of Institute of Science and Technology, 2014, 19(2): 89-93

scholarly journals Determination of Metochloropramide Hydrochloride by Spectrophotometric Method by using Diazotized p-nitro aniline reagent

2020 ◽  
Vol 10 (01) ◽  
pp. 68-73
Author(s):  
Intidhar D. Sulaiman ◽  
Walaa A. Abd Alrada
Keyword(s):  
Alkaline Medium ◽  
Spectrophotometric Method ◽  
Azo Dye ◽  
Limit Of Detection ◽  
Pharmaceutical Preparation ◽  
Molar Absorptivity ◽  
Water Soluble ◽  
Amino Group ◽  
Primary Amino

New simple, sensitive, accurate, and inexpensive spectrophotometric technique has been developed for the estimation of Metochloropramide hydrochloride [MCP-HCl] in pure and pharmaceutical preparation. This technique is based on the diazotization of a primary amino group of Metochloropramide hydrochloride [MCP-HCl] with NaNo2 and HCl followed by coupling with p-nitro aniline in alkaline medium to obtain a stable red-colored water-soluble azo-dye, show a maximum absorption (λmax) at 513. 50nm. Bear,s low is obeyed in the concentration range of (0.2–25) μg.ml-1 with molar absorptivity of 2.313×103L.mol-1.cm-1and sandall’s sensitivity 0.0145 μg.mL-2. The limit of detection (LOD) and limit of quantitative were 0.182 μg.mL-1and 0.553 μg.mL-1, respectively. The proposed technique successfully applied to (tablets, syrup, and injection).

scholarly journals Validated spectophotometric methods for the assay of cinitapride hydrogen tartrate in pharmaceuticals

2013 ◽  
Vol 19 (2) ◽  
pp. 303-311
Author(s):  
K.V.V. Satyanarayana ◽  
Rao Nageswara
Keyword(s):  
Hydrochloric Acid ◽  
Alkaline Medium ◽  
Sodium Nitrite ◽  
Azo Dyes ◽  
Molar Absorptivity ◽  
Optimum Conditions ◽  
Pharmaceutical Tablets ◽  
Spectrophotometric Methods ◽  
Ich Guidelines

Three simple, selective and rapid spectrophotometric methods have been established for the determination of cinitapride hydrogen tartrate (CHT) in pharmaceutical tablets. The proposed methods are based on the diazotization of CHT with sodium nitrite and hydrochloric acid, followed by coupling with resorcinol, 1-benzoylacetone and 8-hydroxyquinoline in alkaline medium for methods A, B and C respectively. The formed azo dyes are measured at 442, 465 and 552 nm for methods A, B and C respectively. The parameters that affect the reaction were carefully optimized. Under optimum conditions, Beer?s law is obeyed over the ranges 2.0-32.0, 1.0-24.0 and 1.0-20.0 ?g. mL-1 for methods A, B, and C, respectively. The calculated molar absorptivity values are 1.2853 x104, 1.9624 x104 and 3.92 x104 L.mol-1.cm-1 for methods A, B and C, respectively. The results of the proposed procedures were validated statistically according to ICH guidelines. The proposed methods were successfully applied to the determination of CHT in Cintapro tablets without interference from common excipients encountered.

scholarly journals Spectrophotometric determination of metoclopramide hydrochloride in pharmaceutical tablets, by diazotization-coupling method with 1-naphthol as the coupling agent

2010 ◽  
Vol 7 (1) ◽  
pp. 704-712
Author(s):  
Baghdad Science Journal
Keyword(s):  
Detection Limit ◽  
Azo Dye ◽  
Diazonium Salt ◽  
Molar Absorptivity ◽  
British Pharmacopoeia ◽  
Pharmaceutical Tablets ◽  
Hydrochloric Acid Medium ◽  
Metoclopramide Hydrochloride ◽  
Sensitive Spectrophotometric Method

Simple, rapid and sensitive spectrophotometric method was proposed for the analysis of metoclopramide hydrochloride (MPH) in pure form as well as in pharmaceutical tablets. The method is based on the diazotization reaction of MPH with sodium nitrite in hydrochloric acid medium to form diazonium salt, which is coupled with 1-naphthol in sodium hydroxide medium to form azo dye, showing absorption maxima at 550 nm. Beer’s law is obeyed in the concentration range of 0.4 – 18 µg mL-1 of MPH with detection limit 0.5448 µg mL-1. The molar absorptivity and Sandell’s sensitivity are 3.4969 × 104 L mol-1 cm-1 and 0.0101 µg cm-2, respectively. The method was successfully applied to the determination of MPH in pharmaceutical tablets without any interference from common excipients used as additives in tablets. The results agree favorably with the official British Pharmacopoeia method.

scholarly journals SYNTHESIS OF NEW SUBSTITUTED PROCAINE HYDROCHLORIDE COMPOUNDS AND THEIR USE IN SPECTROPHOTOMETRIC DETERMINATION OF TETRACYCLINE HYDROCHLORIDE THROUGH DIAZOTIZATION-COUPLING REACTIONS

2021 ◽  
Vol 18 (39) ◽  
pp. 14-32
Author(s):  
Hind Sadiq Al-WARD ◽  
Mouayed Qassssim AL-ABACHI ◽  
Mohammed Rifaat AHMED
Keyword(s):  
Stability Constant ◽  
Thermodynamic Parameters ◽  
Coupling Reaction ◽  
Water Soluble ◽  
Procaine Hydrochloride ◽  
Effect Of Temperature ◽  
Basic Medium ◽  
Fast Method ◽  
The Stability

Background: Tetracycline is one of the most important antibiotics. It is used to treat many different bacterial infections. It is often used in treating severe acne, or sexually transmitted diseases such as syphilis, gonorrhea, or chlamydia. In some cases, tetracycline is used when penicillin or another antibiotic cannot be used to treat serious infections such as the ones caused by Bacillus anthracis, Listeria, Clostridium, Actinomyces. Aim: synthesized a new novel reagent used to determine TCH spectrophotometrically by using diazonium and coupling reaction. Methods: Four new substituted procaine derivatives were prepared by simple organic methods using aniline derivatives. A spectrophotometric approach was established for the micro-determination of TCH. The stoichiometry was investigated using mole ratio and continuous variation methods, and the stability constant was also estimated. The ΔG, ΔH, and ΔS were determined as thermodynamic parameters for evaluating the effect of temperature on the reaction. Results: Substituted procaine derivatives were prepared, and o-hydroxy procaine seems to be the best reagent used to determine TCH by diazotization and coupling reaction. The result was a yellow water-soluble dye with a maximum absorbance of 380 nm. The reaction conditions were studied and optimized. Beers law was obeyed over a concentration range (2.5–50) μg.mL-1 for TCH. The molar absorptivity was (14.4669.103) L.mol-1.cm-1, and the detection limit was (0.5052) μg.mL-1. The stoichiometry of the formed product was found 1:1 (o-hydroxyprocaine: TCH). The stability constant indicated that the product formed was stable, and the thermodynamic parameters showed that the diazonium salt reaction was preferred to occur at a low temperature. Conclusions: a simple, accurate, and fast method was developed to determine TCH in pure form and pharmaceuticals by coupling the TCH with a newly synthesized procaine derivative reagent (o-hydroxy procaine) in a basic medium.

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