Spectrophotometric determination of etamsylate in pharmaceuticals using ferric chloride based on complex formation reactions

The present study describes two simple and selective spectrophotometric methods for the rapid determination of etamsylate (ETM) in bulk and in capsule formulations. The methods are based on the oxidation of ETM with ferric chloride in neutral medium and subsequent chelation of the resulting iron(II) with 1,10-phenanthroline (Phen) (method A) and with 2,2?-bipyridyl (Bipy) (method B). The resulting red colored chromogens are measured at 510 and 520 nm, in method A and B, respectively. In both methods, the absorbance is found to increase linearly with increasing ETM concentration. Beer?s law is obeyed over the ranges 0.5-10 and 0.8-16 ?g/ml for method A and B, respectively. The calculated molar absorptivity values are 2.17?104 and 1.65?104 l/mol/cm for method A and B, respectively, and the corresponding sandell sensitivities are 0.012 and 0.016 ?g/cm2. Intra-day and inter-day precision and accuracy of the methods were established according to ICH guidelines. The proposed methods were applied to determine ETM in dosage forms and the results were statistically compared with that of an official BP method.

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Application of Cerium (IV) as an Oxidimetric Agent for the Determination of Ethionamide in Pharmaceutical Formulations

Journal of Pharmaceutics ◽

10.1155/2016/5410573 ◽

2016 ◽

Vol 2016 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Kanakapura Basavaiah ◽

Nagib A. S. Qarah ◽

Sameer A. M. Abdulrahman

Keyword(s):

Quality Control ◽

Pharmaceutical Formulations ◽

Molar Absorptivity ◽

Sample Solution ◽

Standing Time ◽

Spectrophotometric Methods ◽

Ich Guidelines ◽

Back Titration ◽

Bulk Drug

Two simple methods are described for the determination of ethionamide (ETM) in bulk drug and tablets using cerium (IV) sulphate as the oxidimetric agent. In both methods, the sample solution is treated with a measured excess of cerium (IV) solution in H2SO4 medium, and after a fixed standing time, the residual oxidant is determined either by back titration with standard iron (II) solution to a ferroin end point in titrimetry or by reacting with o-dianisidine followed by measurement of the absorbance of the orange-red coloured product at 470 nm in spectrophotometry. In titrimetry, the reaction proceeded with a stoichiometry of 1 : 2 (ETM : Ce (IV)) and the amount of cerium (IV) consumed by ETM was related to the latter’s amount, and the method was applicable over 1.0–8.0 mg of drug. In spectrophotometry, Beer’s law was obeyed over the concentration range of 0.5–5.0 μg/mL ETM with a molar absorptivity value of 2.66 × 104 L/(mol·cm). The limits of detection (LOD) and quantification (LOQ) calculated according to ICH guidelines were 0.013 and 0.043 μg/mL, respectively. The proposed titrimetric and spectrophotometric methods were found to yield reliable results when applied to bulk drug and tablets analysis, and hence they can be applied in quality control laboratories.

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Spectrophotometric determination of Uranium through complex formation with roxarsone

Mediterranean Journal of Chemistry ◽

10.13171/mjc106020071479nmmaa ◽

2020 ◽

Vol 10 (6) ◽

pp. 634

Author(s):

Nashat Mohamed Alanwar Abd alaty

Keyword(s):

Complex Formation ◽

Inductively Coupled Plasma ◽

Rapid Determination ◽

Molar Absorptivity ◽

Pure Form ◽

Metallic Ions ◽

Font Size ◽

Uranium Ore ◽

Inductively Coupled

A new sensitive, accurate, and non-extractive spectrophotometric method was developed for the rapid determination of Uranium in pure form and Uranium ore using roxarsone. The procedure was based on the complex formation between Uranium (VI) and roxarsone. This showed maximum absorption at λmax 395 nm with a linear relationship in the concentration range from (20-100 µg mLˉ¹) with a molar absorptivity 9.57×103(1mol-1 cm-1). Inductively Coupled Plasma mass spectroscopy (ICP-MS) was used in the study of the interferences caused by some metallic ions, which were effectively masked by tartaric acid and diethylenetriaminepenta-acetic acid (DTPA). The method holds its accuracy and precision well when applied to the determination of the studied Uranium in its pure form and Uranium ore.

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Simple Methods for the Spectrophotometric Determination of Carvedilol

ISRN Spectroscopy ◽

10.5402/2012/373215 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6

Author(s):

Divya N. Shetty ◽

B. Narayana

Keyword(s):

Charge Transfer ◽

Complex Formation ◽

Confidence Level ◽

Charge Transfer Complex ◽

Condensation Reaction ◽

Pharmaceutical Preparations ◽

Molar Absorptivity ◽

Spectrophotometric Methods ◽

Accuracy And Precision

Two simple spectrophotometric methods are described for the determination of carvedilol (CAR). Method A is the condensation reaction of CAR with p-dimethylaminobenzaldehyde (PDAB), and the reaction mixture exhibits maximum absorbance at 601 nm. Method B is based on the charge transfer complex formation of CAR with p-chloranil; the color developed is measured at 662 nm. The calibration graphs are found to be linear over 50.00–250.00 and 20.00–100.0 μg mL−1 with molar absorptivity values of 0.92×103 and 0.257×104 L mol−1cm−1 for CAR-PDAB and CAR-p-chloranil, respectively. Statistical comparisons of the results are performed with regard to accuracy and precision using Student’s t-test and F-test at 95% confidence level. The methods are successfully employed for the determination of CAR in pharmaceutical preparations, and the results agree favorably with the reference and proposed methods.

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New, simple and validated UV-spectrophotometric methods for the estimation of sodium usnate in preparations

Macedonian Journal of Chemistry and Chemical Engineering ◽

10.20450/mjcce.2010.162 ◽

2010 ◽

Vol 29 (2) ◽

pp. 157 ◽

Cited By ~ 2

Author(s):

Ivana Savić ◽

Goran Nikolić ◽

Ivan Savić ◽

Saša Zlatković ◽

Dragiša Djokić

Keyword(s):

Phosphate Buffer ◽

Pharmaceutical Preparations ◽

High Sensitivity ◽

Cost Effective ◽

Sensitivity Coefficient ◽

Molar Absorptivity ◽

Spectrophotometric Methods ◽

Ich Guidelines ◽

Beer’S Law

New, simple, cost effective, accurate and reproducible UV-spectrophotometric methods were developed and validated for the estimation of sodium usnate in pharmaceutical preparations. Sodium usnate was estimated at 290 nm in water and phosphate buffer (pH 3):methanol (11:20 V/V). Beer’s law was obeyed in the concentration range of 0.1–5 μg·cm−3 (r = 0.997) in water and 1–12 μg·cm−3 (r = 0.999) in the phosphate buffer:methanol. The apparent molar absorptivity and Sandell’s sensitivity coefficient were found to be 3.16×104 dm3·mol−1·cm−1 and 11.58 ng·cm–2/0.001 A in water and 3.72×104 dm3·mol−1·cm−1 and 9.83 ng·cm–2/0.001 A in phosphate buffer:methanol, respectively, indicating the high sensitivity of the proposed methods. These methods were tested and validated for various parameters according to ICH guidelines. The detection and quantitation limits were found to be 0.0721 and 0.2163 μg·cm–3 in water and 0.163, 0.489 μg·cm−3 in phosphate buffer:methanol, respectively. The proposed methods were successfully applied for the determination of sodium usnate in pharmaceutical preparations. The results demonstrated that the procedure is accurate, precise and reproducible (R.S.D. < 2 %).

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New Spectrophotometric Methods for Estimation of Perindopril Erbumine in Bulk and Pharmaceutical Formulations

Journal of Scientific Research ◽

10.3329/jsr.v6i2.16106 ◽

2014 ◽

Vol 6 (2) ◽

pp. 319-327

Author(s):

A. Unnisa ◽

K. V. G. Raju ◽

K. Balaji ◽

A. N. Jyothi ◽

T. S. Kumar

Keyword(s):

Regression Analysis ◽

Citric Acid ◽

Pharmaceutical Formulations ◽

Bulk Sample ◽

Molar Absorptivity ◽

Dosage Forms ◽

Spectrophotometric Methods ◽

Perindopril Erbumine ◽

Detection And Quantification

Three rapid, simple, inexpensive, precise, and accurate spectrophotometric procedures were developed for the determination of Perindopril erbumine (PPE) using cobalt-thiocyanate, citric acid and 2,3- dichloro-5,6-dicyano benzoquinone in bulk sample and in dosage forms. The procedures are based on the coordination complex of the drug (electron donor) and the chromogenic reagents used. The colored products are extracted into non aqueous solvents and measured spectrophotometrically at the optimum ?maxfor each complex. Regression analysis of Beer-Lambert plots showed good correlation in the concentration range of 30-70 µg mL?1, 4-20 µg mL?1 and 20-60 µg mL?1 for cobalt-thiocyanate, citric acid and 2,3- dichloro-5,6-dicyano benzoquinone, respectively. The apparent molar absorptivity, Sandells sensitivity, detection and quantification limits were calculated. The developed methods were successfully applied for the determination of PPE in bulk and pharmaceutical formulations without any interference from common excipients and hence can be used for their routine analysis. Keywords: Perindopril erbumine; Spectrophotometry; Cobalt-thiocyanate; Citricacid-acetic anhydride. © 2014 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved. doi: http://dx.doi.org/10.3329/jsr.v6i2.16106 J. Sci. Res. 6 (2), 319-327 (2014)

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Spectrophotometric Estimation of Cefuroxime and Ceftazidime in Bulk and in Dosage Forms

Scientia Pharmaceutica ◽

10.3797/scipharm.aut-01-15 ◽

2001 ◽

Vol 69 (2) ◽

pp. 143-150 ◽

Cited By ~ 1

Author(s):

A. Amin ◽

H. Khalli ◽

H. Saleh

Keyword(s):

Molar Absorptivity ◽

Dosage Forms ◽

Acetate Buffer Solution ◽

Sodium Fluorescein ◽

Buffer Solution ◽

Experimental Conditions ◽

Spectrophotometric Methods ◽

Relative Standard ◽

Optimum Concentration Range

Three simple, accurate and sensitive spectrophotometric methods (A, B and C) for the determination of cefuroxime and ceftazidime in bulk samples and in dosage forms are described. They are based on the reaction with nitrous acid forming a nitroso derivatives which can be measured at λmax 350 and 355 nm for cefuroxime (I) and ceftazidime (II), respectively (method A) or by oxidation of drug I or II with an excess of freshly prepared hypobromite and the residual hypobromite was treated with sodium fluorescein at the optimum experimental conditions and measured at λmax at 517 nm (method B). Method C is based on the formation of tris (0-phenanthroline) iron(II) complex (ferroin) upon the oxidation of the studied drug I or II with an iron (III)-o-phenanthroline mixture in acetate buffer solution of pH 3.6 and measuring at λmax 509 nm. Regression analysis of Beer-Lambert plots showed good correlation in the concentration ranges 0.2 – 6.0, 0.2 – 3.2 and 0.1 – 5.6 μg ml−1 for methods A, B and C, respectively. The apparent molar absorptivity, Sandell sensitivity, detection and quantitation limits were calculated. For more accurate results, Ringbom optimum concentration range was 0.2 – 5.6 μg ml−1. The validity of the proposed methods was tested by analysing dosage forms containing the studied drugs I and II. The relative standard deviations were ≤ 1.25% with recoveries 98.6 – 101.4% .

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Determination of Histidine by Atomic Absorption Spectroscopy

Journal of AOAC International ◽

10.1093/jaoac/80.4.741 ◽

1997 ◽

Vol 80 (4) ◽

pp. 741-745 ◽

Cited By ~ 1

Author(s):

Amina M El-Brashy ◽

Sheikha M Al-Ghannam

Keyword(s):

Thin Layer ◽

Atomic Absorption ◽

Standard Addition ◽

Dosage Forms ◽

Neutral Medium ◽

Official Method ◽

Regression Equations ◽

Spectrophotometric Methods ◽

Separation Results

Abstract Two atomic absorption spectrophotometric methods are described for determination of histidine. The first is based on reaction of histidine with mercury(II) ions in phosphate buffer (pH 9). The second is based on reaction of histidine with iron(III) ions in neutral medium. The precipitate formed in both methods is separated by centrifugation, and the equivalent Hg(II) or Fe(III) ions as well as surplus ions in the filtrate are determined by atomic absorption at 253.6 and 248.3 nm for Hg and Fe, respectively. Amounts of histidine are calculated from calibration graphs prepared by standard addition methods or by regression equations. The procedures were successfully applied to assay of histidine in dosage forms after thin-layer chromatographic separation. Results compared favorably with those of the official method.

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Redox-Reaction Based Spectrophotometric Assay of Isoniazid in Pharmaceuticals

ISRN Analytical Chemistry ◽

10.1155/2014/717019 ◽

2014 ◽

Vol 2014 ◽

pp. 1-11 ◽

Cited By ~ 3

Author(s):

N. Swamy ◽

K. N. Prashanth ◽

K. Basavaiah

Keyword(s):

Prussian Blue ◽

Redox Reaction ◽

Molar Absorptivity ◽

Spectrophotometric Assay ◽

Commercial Formulation ◽

Spectrophotometric Methods ◽

Ich Guidelines ◽

Beer's Law ◽

Beer’S Law

Two spectrophotometric methods are described for the determination of isoniazid (INH) in pharmaceuticals. In the first method (FCR method), INH is reacted with Folin-Ciocalteu reagent in Na2CO3 medium and the resulting blue colored chromogen measured at 760 nm. Iron(II), formed as a result of reaction between INH and iron(III), is made to react with ferricyanide, and the resulting Prussian blue is measured at 760 nm, basing the second method (FFC method). The conditions for better performance are optimized. Beer’s law is obeyed in the concentration ranges 0.5–10 and 0.2–3.0 μg mL−1 for FCR method and FFC methods, respectively, with corresponding molar absorptivity values of 1.12×104 and 4.55×104 L mol−1 cm−1. The methods are validated for accuracy, precision, LOD, LOQ, robustness, and ruggedness as per the current ICH guidelines. The validated methods were successfully applied to quantify INH in its commercial formulation with satisfactory results; hence the methods are suitable for isoniazid determination in bulk drugs and pharmaceuticals.

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Titrimetric and spectrophotometric assay of diethylcarbamazine citrate in formulations using iodate and iodide mixture as reagents

Brazilian Journal of Pharmaceutical Sciences ◽

10.1590/s1984-82502015000100005 ◽

2015 ◽

Vol 51 (1) ◽

pp. 43-52 ◽

Cited By ~ 3

Author(s):

Nagaraju Swamy ◽

Kudige Nagaraj Prashanth ◽

Kanakapura Basavaiah

Keyword(s):

Molar Absorptivity ◽

Potassium Iodate ◽

Spectrophotometric Methods ◽

Accuracy And Precision ◽

Ich Guidelines ◽

Diethylcarbamazine Citrate ◽

Back Titration ◽

Bulk Drug ◽

Reaction Stoichiometry

One titrimetric and two spectrophotometric methods are proposed for the determination of diethylcarbamazine citrate (DEC) in bulk drug and in formulations using potassium iodate and potassium iodide as reagent. The methods employ the well-known analytical reaction between iodate and iodide in the presence of acid. In titrimetry (method A), the drug was treated with a measured excess of thiosulfate in the presence of unmeasured excess of iodate-iodide mixture and after a standing time of 10 min, the surplus thiosulfate was determined by back titration with iodine towards starch end point. Titrimetric assay is based on a 1:3 reaction stoichiometry between DEC and iodine and the method is applicable over 2.0-10.0 mg range. The liberated iodine is measured spectrophotometrically at 370 nm (method B) or the iodine-starch complex measured at 570 nm (method C). In both methods, the absorbance is found to be linearly dependent on the concentration of iodine, which in turn is related to DEC concentration. The calibration curves are linear over 2.5-50 and 2.5-30 µg mL-1 DEC for method B and method C, respectively. The calculated molar absorptivity and Sandell sensitivity values were 6.48×103 L mol-1 cm-1 and 0.0604 µg cm-2, respectively, for method B, and their respective values for method C are 9.96×103 L mol-1 cm-1 and 0.0393 µg cm-2. The intra-day and inter-day accuracy and precision studies were carried out according to the ICH guidelines. The methods were successfully applied to the analysis of DEC formulations.

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Determination of olanzapine by spectrophotometry using permanganate

Brazilian Journal of Pharmaceutical Sciences ◽

10.1590/s1984-82502009000300020 ◽

2009 ◽

Vol 45 (3) ◽

pp. 539-550 ◽

Cited By ~ 10

Author(s):

Nagaraju Rajendraprasad ◽

Kanakapura Basavaiah

Keyword(s):

Alkaline Medium ◽

Standard Addition ◽

Molar Absorptivity ◽

Intermediate Precision ◽

Green Color ◽

Spectrophotometric Methods ◽

Ich Guidelines ◽

Bluish Green ◽

Optimized Conditions

Two new spectrophotometric methods using permanganate as the oxidimetric reagent for the determination of olanzapine (OLP) were developed and validated as per the current ICH guidelines. The methods involved the addition of known excess of permanganate to OLP in either acid or alkaline medium followed by the determination of unreacted permanganate at 550 nm (method A) or bluish-green color of manganate at 610 nm (method B). The decrease in absorbance in method A or increase in absorbance in method B as a function of concentration of OLP was measured and related to OLP concentration. Under optimized conditions, Beer's law was obeyed over the ranges 2.0 to 20 and 1.0 to 10 μg mL-1 in method A and method B, respectively. The calculated molar absorptivity values were 1.34 x 10(4) and 2.54 x 10(4) l mol-1cm-1 for method A and method B respectively, and the respective Sandell sensitivities were 0.0233 and 0.0123 μg cm-2. The LOD and LOQ for method A were calculated to be 0.37 and 1.13 μg mL-1and the corresponding values for method B were 0.16 and 0.48 μg mL-1. Intermediate precision, expressed as RSD was in the range 0.51 to 2.66 %, and accuracy, expressed as relative error ranged from 0.79 to 2.24 %. The proposed methods were successfully applied to the assay of OLP in commercial tablets with mean percentage recoveries of 102 ±1.59 % (method A) and 101 ±1.53 % (method B). The accuracy and reliability of the methods were further confirmed by performing recovery tests via standard addition procedure.

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