SPECTROPHOTOMETRIC METHODS FOR DETERMINATION OF SOFOSBUVIR AND DACLATASVIR IN PURE AND DOSAGE FORMS

Objective: Two simple, sensitive and accurate spectrophotometric methods have been developed for the determination of sofosbuvir (SOF) and daclatasvir (DAC) in pure forms and pharmaceutical formulations. Methods: The proposed methods are based on the oxidation of SOF and DAC by a known excess of cerium(IV) ammonium nitrate in sulphuric acid medium followed by determination of unreacted cerium(IV) by adding a fixed amount of indigo carmine (IC) and alizarin red S (ARS) dyes followed by measuring the absorbance at 610 and 360 nm, respectively. The experimental conditions affecting the reaction were studied and optimized. Results: The beer’s law was obeyed in the concentration ranges of 0.2-3.0, 0.2-4.0 for SOF and 0.5-4.5 and 0.5-5.0 μg/ml for DAC using IC and ARS methods, respectively with a correlation coefficient ≥ 0.9991. The calculated molar absorptivity values are 2.354 × 104, 1.933 × 104 for SOF and 1.786 × 104 and 2.015 × 104 L/mol. cm for DAC using IC and ARS methods, respectively u. The limits of detection and quantification are also reported. Intra-day and inter-day precision and accuracy of the methods have been evaluated. Conclusion: The methods were successfully applied to the assay of SOF and DAC in tablets and the results were statistically compared with those of the reference method by applying Student’s t-test and F-test. No interference was observed from the common tablet excipients. The accuracy and reliability of the methods were further ascertained by performing recovery studies using the standard addition method.

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Sensitive Bromatometric Methods for the Determination of Sumatriptan Succinate in Pharmaceutical Formulations

E-Journal of Chemistry ◽

10.1155/2011/562749 ◽

2011 ◽

Vol 8 (1) ◽

pp. 269-275 ◽

Cited By ~ 3

Author(s):

K. V. V. Satyanarayana ◽

P. Nageswara Rao

Keyword(s):

Indigo Carmine ◽

Pharmaceutical Formulations ◽

Molar Absorptivity ◽

Experimental Conditions ◽

Fixed Amount ◽

Spectrophotometric Methods ◽

Sumatriptan Succinate ◽

Ich Guidelines ◽

Label Claim

Two simple and sensitive spectrophotometric methods are described for the determination of sumatriptan succinate (STS) in pure and tablets using bromate-bromide as the bromination reagent in acid medium and two dyes as subsidiary reagents. The two methods are based on the bromination of STS by a known excess ofin situgenerated bromine followed by determination of unreacted bromine by reacting with a fixed amount of methyl orange (Method A) or indigo carmine (Method B) and measuring the absorbance at 508 or 610 nm. In both methods, the amount of bromine reacted corresponds to the amount of STS. The experimental conditions for the assay have been optimized. In two methods, the absorbance was found to increase linearly with the concentration of STS at the respective wavelengths. Beer’s law was obeyed over the ranges 0.2-1.6 and 2.0-12.0 μg mL-1for method A and method B respectively and the respective molar absorptivity values were 1.898×105and 2.71×104L mol-1cm-1. The statistical analysis of the methods was validated according to the present ICH guidelines. The proposed methods were applied to the analysis of tablet form of STS and the results tallied well with the label claim.

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Cerimetric determination of simvastatin in pharmaceuticals based on redox and complex formation reactions

Eclética Química Journal ◽

10.26850/1678-4618eqj.v33.2.2008.p21-28 ◽

2018 ◽

Vol 33 (2) ◽

pp. 21

Author(s):

Kanakapura Basavaiah ◽

Okram Zenita Devi

Keyword(s):

Limit Of Detection ◽

Reference Method ◽

Standard Addition ◽

Molar Absorptivity ◽

Experimental Conditions ◽

Spectrophotometric Methods ◽

Fixed Quantity ◽

Bulk Drug ◽

Student’S T

Two sensitive spectrophotometric methods are described for the determination of simvastatin (SMT) in bulk drug and in tablets. The methods are based on the oxidation of SMT by a measured excess of cerium (IV) in acid medium followed by determination of unreacted oxidant by two different reaction schemes. In one procedure (method A), the residual cerium (IV) is reacted with a fixed concentration of ferroin and the increase in absorbance is measured at 510 nm. The second approach (method B) involves thereduction of the unreacted cerium (IV) with a fixed quantity of iron (II), and the resulting iron (III) is complexed with thiocyanate and the absorbance measured at 470 nm. In both methods, the amount of cerium (IV) reacted corresponds to SMT concentration. The experimental conditions for both methods were optimized. In method A, the absorbance is found to increase linearly with SMT concentration (r = 0.9995) whereas in method B, the same decreased (r = -0.9943). The systems obey Beer’s law for 0.6-7.5 and 0.5-5.0 μg mL-1 for method A and method B, respectively. The calculated molar absorptivity values are 2.7 X 104 and 1.06 X 105 Lmol-1 cm-1, respectively; and the corresponding sandel sensitivity values are 0.0153 and 0.0039μg cm-2, respectively. The limit of detection (LOD) and quantification (LOQ) are reported for both methods. Intra-day and inter-day precision, and accuracy of the methods were established as per the current ICH guidelines. The methods were successfully applied to the determination of SMT in tablets and the results were statistically compared with those of the reference method by applying the Student’s t-test and F-test. No interference was observed from the common excipients added to tablets. The accuracy and validity of the methods were further ascertained by performing recovery experiments via standard addition procedure.

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Rapid titrimetric and spectrophotometric determination of ofloxacin in pharmaceuticals using N-bromosuccinimide

Brazilian Journal of Pharmaceutical Sciences ◽

10.1590/s1984-82502011000200006 ◽

2011 ◽

Vol 47 (2) ◽

pp. 251-260 ◽

Cited By ~ 2

Author(s):

Kanakapura Basavaiah Vinay ◽

Hosakere Doddarevanna Revanasiddappa ◽

Okram Zenita Devi ◽

Pavagada Jagannathamurthy Ramesh ◽

Kanakapura Basavaiah

Keyword(s):

Indigo Carmine ◽

Reference Method ◽

Standard Addition ◽

Addition Method ◽

Fixed Amount ◽

Spectrophotometric Methods ◽

Analytical Reagent ◽

Bulk Drug ◽

Reaction Stoichiometry

One titrimetric and two spectrophotometric methods have been described for the determination of ofloxacin (OFX) in bulk drug and in tablets, employing N-Bromosuccinimide as an analytical reagent. The proposed methods involve the addition of a known excess of NBS to OFX in acid medium, followed by determination of unreacted NBS. In titrimetry, the unreacted NBS is determined iodometrically, and in spectrophotometry, unreacted NBS is determined by reacting with a fixed amount of either indigo carmine (Method A) or metanil yellow (Method B). In all the methods, the amount of NBS reacted corresponds to the amount of OFX. Titrimetry allows the determination of 1-8 mg of OFX and the calculations are based on a 1:5 (OFX:NBS) reaction stoichiometry. In spectrophotometry, Beer's law is obeyed in the concentration ranges 0.5-5.0 µg/mL for method A and 0.3-3.0 µg/mL for method B. The molar absorptivities are calculated to be 5.53x10(4) and 9.24x10(4) L/mol/cm for method A and method B, respectively. The methods developed were applied to the assay of OFX in tablets, and results compared statistically with those of a reference method. The accuracy and reliability of the methods were further ascertained by performing recovery tests via the standard-addition method.

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Validated Spectrophotometric Determination of Rizatriptan Benzoate in Pharmaceutical Formulations using Alizarin Derivatives

International Journal of Pharmaceutical Quality Assurance ◽

10.25258/ijpqa.10.1.2 ◽

2019 ◽

Vol 10 (01) ◽

Author(s):

El Sheikh R ◽

Hassan W. S. ◽

Gouda A. A. ◽

Al OwairdhiA. ◽

Al Hassani K K H

Keyword(s):

Standard Addition ◽

Pharmaceutical Formulations ◽

Molar Absorptivity ◽

Optimum Conditions ◽

Reaction Conditions ◽

Alizarin Red ◽

Rizatriptan Benzoate ◽

Spectrophotometric Methods ◽

Relative Standard

Two simple, sensitive, accurate, precise and economical spectrophotometric methods have been developed and validated for the determination of rizatriptan benzoate (RZT) in pure form and pharmaceutical formulations. These methods were based on the formation of charge transfer complex between RZT as n-electron donor and alizarin red S (ARS) or quinalizarin (Quinz) as π-acceptor in methanol to form highly colored chromogens which showed an absorption maximum at 532 and 574 nm using ARS and Quinz, respectively. The optimization of the reaction conditions such as the type of solvent, reagent concentration and reaction time were investigated. Under the optimum conditions, Beer’s law is obeyed in the concentration ranges 1.0-16 and 2.0-20 g mL-1 using ARS and Quinz, respectively with good correlation coefficient (r2 ≥ 0.9996) and with a relative standard deviation (RSD% ≤ 1.16). The molar absorptivity, Sandell sensitivity, detection and quantification limits were also calculated. The methods were successfully applied to the determination of RZT in its pharmaceutical formulations and the validity assesses by applying the standard addition technique. Results obtained by the proposed methods for the pure RZT and commercial tablets agreed well with those obtained by the reported method.

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New Sensitive Spectrophotometric Methods for the Determination of Raloxifene Hydrochloride in Pharmaceuticals Using Bromate-Bromide,Methyl Orange and Indigo Carmine

E-Journal of Chemistry ◽

10.1155/2006/472186 ◽

2006 ◽

Vol 3 (4) ◽

pp. 242-249 ◽

Cited By ~ 2

Author(s):

K Basavaiah ◽

U. R. Anil Kumar

Keyword(s):

Methyl Orange ◽

Indigo Carmine ◽

Reference Method ◽

Standard Addition ◽

Fixed Amount ◽

Spectrophotometric Methods ◽

Hydrochloric Acid Medium ◽

Student’S T ◽

Raloxifene Hydrochloride

Two new sensitive spectrophotometric methods are proposed for the determination of raloxifene hydrochloride (RLX) using bromate-bromide mixture and two dyes, methyl orange and indigocarmine, as reagents. The methods entail the addition of a known excess of bromate-bromide mixture to RLX in hydrochloric acid medium followed by determination of residual bromine by reacting with a fixed amount of either methyl orange and measuring the absorbance at 520 nm (Method A) or indigo carmine and measuring the absorbance at 610 nm (Method B). In both methods, the amount of bromine reacted corresponds to the amount of RLX. The absorbance is found to increase linearly with concentration of RLX. Under the optimum conditions, RLX could be assayed in the concentration range 0.1-2.0 and 0.5-6.0 μg mL-1by method A and method B, respectively. The apparent molar absorptivities are calculated to be 1.9×105and 4.5×104L mol-1cm-1for method A and method B, respectively, and the corresponding Sandell sensitivity values are 0.003 and 0.011 μg cm-2. The limits of detection and quantification are also reported for both methods. Intra-day and inter-day precision and accuracy of the developed methods were evaluated as per the current ICH guidelines. The methods were successfully applied to the assay of RLX in its tablet formulation and the results were compared with those of a reference method by calculating the Student’s t-value and F-value. No interference was observed from common tablet adjuvants. The accuracy and reliability of the methods were further ascertained by recovery experiments via standard-addition procedure.

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Application of bromate-bromide mixture as a green brominating agent for the spectrophotometric determination of atenolol in pharmaceuticals

Chemical Industry and Chemical Engineering Quarterly ◽

10.2298/ciceq110721045p ◽

2012 ◽

Vol 18 (1) ◽

pp. 43-52 ◽

Cited By ~ 1

Author(s):

Nagaraj Prashanth ◽

Kanakapura Basavaiah ◽

Sameer Abdulrahman ◽

Nagaraju Rajendraprasad ◽

Basavaiah Vinay

Keyword(s):

Reference Method ◽

Standard Addition ◽

Pharmaceutical Formulations ◽

Molar Absorptivity ◽

Spectrophotometric Methods ◽

Highly Sensitive ◽

Bromination Reaction ◽

Excess Iodide ◽

Good Agreement

Two highly sensitive spectrophotometric methods are proposed for the quantification of atenolol (ATN) in pure drug as well as in pharmaceutical formulations. The methods are based on the bromination reaction of ATN with a known excess of bromate-bromide mixture in acid medium followed by the determination of unreacted bromine. The residual bromine is determined by its reaction with excess iodide and the liberated iodine (I3?) is either measured at 360 nm (method A) or reacted with starch followed by the measurement of the starch-iodine chromogen at 570 nm (method B). Under the optimum conditions, ATN could be assayed in the concentration ranges of 0.5-9.0 and 0.3-6.0?g mL-1 for method A and method B, respectively, with corresponding molar absorptivity values of 2.36?104 and 2.89?104 L/mol.cm. Sandell?s sensitivity values are found to be 0.0113 and 0.0092 ?g/cm2 for method A and method B, respectively. The proposed methods were successfully applied to the analysis of different commercial brands of pharmaceutical formulations and the results obtained by the proposed methods were in good agreement with those obtained using the reference method. The reliability of the methods was further ascertained by recovery studies using standard- addition method.

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Titrimetric and Spectrophotometric Determination of Metaprolol tartrate in Pharmaceuticals Using N-Bromosuccinimide

E-Journal of Chemistry ◽

10.1155/2007/739141 ◽

2007 ◽

Vol 4 (1) ◽

pp. 117-127 ◽

Cited By ~ 1

Author(s):

K. Basavaiah ◽

B. C. Somashekar

Keyword(s):

Methyl Orange ◽

Indigo Carmine ◽

Reference Method ◽

Standard Addition ◽

Reaction Conditions ◽

Fixed Amount ◽

Spectrophotometric Methods ◽

Bulk Drug ◽

Reaction Stoichiometry

One titrimetric and two spectrophotometric methods are presented for the assay of metaprolol tartrate (MPT) in bulk drug and in tablets. The methods employ N-bromosuccinimide (NBS) as the oxidimetric reagent and two dyes, methyl orange and indigo carmine as spectrophotometric reagents. In titrimetry, an acidified solution of MPT is treated with a known excess amount of NBS and after a definite time, the unreacted oxidant is determined by iodometric back titration. Spectrophotometry involves adding a measured excess of NBS to MPT in acid medium followed by determination of residual NBS by reacting with a fixed amount of either methyl orange and measuring the absorbance at 520 nm (Method A) or indigo carmine and measuring the absorbance at 610 nm (Method B). In all the methods, the amount of NBS reacted corresponds to the amount of MPT. Reaction conditions have been optimized. Titrimetry allows the determination of 1 - 12 mg of MPT and the calculations are based on a 1: 4 (MPT: NBS) reaction stoichiometry. In spectrophotometry, the measured absorbance is found to increase linearly with the concentration of MPT serving as basis for quantitation. The systems obey Beer’s law for 0.5 - 4.0 μg mL-1and 1.25 - 10.0 μg mL-1for method A and method B, respectively. The apparent absorptivities are calculated to 1.07 × 105be and 4.22 × 104L mol cm-1for method A and method B, respectively. The methods developed were applied to the assay of MPT in commercial tablet formulations, and the results were compared statistically with those of a reference method. The accuracy and reliability of the methods were further ascertained by performing recovery tests via standard-addition method.

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Simple and Selective Titrimetric and Spectrophotometric Methods for the Determination of Loratadine Using Bromate-Bromide, Methyl Orange and Methylene Blue

International Journal of Pharmaceutical Quality Assurance ◽

10.25258/ijpqa.v9i2.13636 ◽

2018 ◽

Vol 9 (2) ◽

Author(s):

Venkatachalam K ◽

Niranjani S ◽

Raju T

Keyword(s):

Methylene Blue ◽

Methyl Orange ◽

Reference Method ◽

Standard Addition ◽

Molar Absorptivity ◽

Stoichiometric Ratio ◽

Fixed Amount ◽

Spectrophotometric Methods ◽

Student’S T

One indirect titrimetric and two indirect visible spectrophotometric methods were described for the determination of loratadine in bulk drug and in its formulations. The methods used bromate-bromide, methyl orange and methylene blue as reagents. In titrimetry (method A), loratadine was treated with a known excess of bromate-bromide mixture in acidic medium and the residual bromine was back titrated iodometrically after the reaction between loratadine and in situ bromine was ensured to be complete. In spectrophotometric methods, the excess of bromine was estimated by treating with a fixed amount of either methyl orange (method B) and measuring the absorbance at 520 nm or methylene blue (method C) and measuring the absorbance at 680 nm. In all the methods, the amount of reacted bromine corresponded to the loratadine content. Titrimetric method was applicable over 1-8 mg range and the calculations were based on a 1:0.666 (loratadine:bromate) stoichiometric ratio. In spectrophotometry, the calibration graphs were found to be linear over 150- 350 and 1.75-3.5 μg mL-1 for method B and method C, respectively, with corresponding molar absorptivity values of 9.15 × 102 and 1.10 × 105 L mol-1 cm-1. Accuracy and precision of the assays were determined by computing the intra-day and inter-day variations at three different levels of loratadine. The methods were successfully applied to the assay of loratadine in tablet preparations and the results were compared with those of a reference method by applying Student’s t and F-tests. No interference was observed from common pharmaceutical excipients. The reliability of the methods was further ascertained by performing recovery tests by standard addition method

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SENSITIVE SPECTROPHOTOMETRIC ASSAY OF MUSCARINIC RECEPTOR ANTAGONIST TOLTERODINE TARTRATE IN BULK DRUG AND PHARMACEUTICAL FORMULATIONS

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2017.v10i8.18794 ◽

2017 ◽

Vol 10 (8) ◽

pp. 346

Author(s):

Ragaa El-sheikh ◽

Wafaa S Hassan ◽

Ayman A Gouda ◽

Marwa M El-gabry

Keyword(s):

Standard Addition ◽

Pharmaceutical Formulations ◽

Molar Absorptivity ◽

Experimental Conditions ◽

Fixed Amount ◽

Spectrophotometric Methods ◽

Accuracy And Precision ◽

Tolterodine Tartrate ◽

Bulk Drug ◽

Student’S T

Objective: Simple, sensitive, and accurate spectrophotometric methods have been developed for the assay of tolterodine tartrate (TOL) in bulk drugand pharmaceutical formulations.Methods: The proposed methods are based on oxidation reaction of TOL with a known excess of cerium(IV) ammonium sulfate as an oxidizing agentin acid medium followed by determination of unreacted oxidant by adding a fixed amount of dye, e.g., amaranth (AM), rhodamine 6G (Rh6G), andindigo carmine (IC) followed by measuring the absorbance at 520, 530, and 610 nm, respectively. The effect of experimental conditions was studiedand optimized.Results: The Beer’s law was obeyed in the concentration ranges of 1.0-10, 1.0-12, and 0.5-9.0 μg/mL using AM, Rh6G, and IC dyes, respectively, witha correlation coefficient ≥0.9995. The calculated molar absorptivity values are 1.868×104, 1.008×104, and 1.623×104 L/mol/cm using AM, Rh6G, andIC dyes, respectively. The limits of detection and quantification were reported. Intraday and interday accuracy and precision of the methods have beenevaluated. No interference was observed from the additives.Conclusion: The proposed methods were successfully applied to the assay of TOL in tablets preparations, and the results were statistically comparedwith those of the reported method by applying Student’s t-test and F-test. The reliability of the methods was further ascertained by performingrecovery studies using the standard addition method.

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Rapid titrimetric and spectrophotometric methods for salbutamol sulphate in pharmaceuticals using N-bromosuccinimide

Acta Pharmaceutica ◽

10.2478/v10007-007-0007-7 ◽

2007 ◽

Vol 57 (1) ◽

pp. 87-98 ◽

Cited By ~ 9

Author(s):

Kanakapura Basavaiah ◽

Bankavadi Somashekar ◽

Veeraiah Ramakrishna

Keyword(s):

Methylene Blue ◽

Acid Medium ◽

Rhodamine B ◽

Reference Method ◽

Standard Addition ◽

Molar Absorptivity ◽

Acetic Acid Medium ◽

Fixed Amount ◽

Salbutamol Sulphate ◽

Spectrophotometric Methods

Rapid titrimetric and spectrophotometric methods for salbutamol sulphate in pharmaceuticals using N-bromosuccinimide One titrimetric and two spectrophotometric methods which are simple, sensitive and rapid are described for the assay of salbutamol sulphate (SBS) in bulk drug and in tablet dosage forms using N-bromosuccinimide (NBS) and two dyes, rhodamine-B and methylene blue, as reagents. In titrimetry, aqueous solution of salbutamol sulphate is treated with a measured excess of NBS in acetic acid medium and after the oxidation of SBS is complete, the unreacted oxidant is determined iodometrically. Spectrophotometric methods entail addition of a known excess of NBS in acid medium followed by the determination of residual oxidant by reacting with a fixed amount of either rhodamine B and measuring the absorbance at 555 nm (method A) or methylene blue and measuring the absorbance at 665 nm (method B). In all methods, the amount of NBS reacting corresponds to the amount of SBS content. Titrimetric method is applicable over 1.74 x 10-4 - 8.68 x 10-4 mol L-1 range and the reaction stoichiometry is found to be 1:6 (SBS:NBS). In spectrophotometric methods, the absorbance is found to increase linearly with the concentration of SBS, which is corroborated by the correlation of coefficients of 0.9993 and 0.9988 for method A and method B, respectively. The systems obey Beer's law for 0.25-1.75 μg mL-1 (method A) and 0.5-5.0 μg mL-1 (method B). The calculated apparent molar absorptivity values were found to be 2.10 x 105 and 6.16 x 104 L mol-1 cm-1, for method A and method B, respectively. The limits of detection and quantification are also reported for both spectrophotometric methods. Intraday and inter-day precision and accuracy for the developed methods were evaluated. The methods were successfully applied to the assay of SBS in tablet and capsule formulations and the results were statistically compared with those of a reference method. No interference was observed from common tablet adjuvants. The accuracy and reliability of the methods were further ascertained by recovery experiments via the standard-addition technique.

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