High Performance Liquid Chromatographic Analysis of Almotriptan Malate in Bulk and Tablets

Purpose: A simple RP-HPLC method has been developed and validated for the determination of almotriptan malate (ATM) in bulk and tablets. Methods: Chromatographic separation of ATM was achieved by using a Thermo Scientific C18 column. A Mobile phase containing a mixture of methanol, water and acetic acid (4:8:0.1 v/v) was pumped at the flow rate of 1 mL/min. Detection was performed at 227 nm. According to ICH guidelines, the method was validated. Results: The calibration curve was linear in the concentration range 5–60 μg/mL for the ATM with regression coefficient 0.9999. The method was precise with RSD <1.2%. Excellent recoveries of 99.60 - 100.80% proved the accuracy of the method. The limits of detection and quantification were found to be 0.025 and 0.075 μg/mL, respectively. Conclusion: The method was successfully applied for the quantification of ATM in tablets with acceptable accuracy and precision

Determination of Bosentan in Pharmaceutical Dosage Forms by High Performance Liquid Chromatography

A simple and sensitive high performance liquid chromatographic method is developed for the estimation of bosentan in pharmaceutical dosage forms. Chromatographic separation of the drug was achieved with an Thermo Scientific C18 column (250 mm × 4.6 mm I.D., 5 μm particle size) analytical column using ammonium bicarbonate (pH was adjusted to 5.0 with phosphoric acid) and acetonitrile (70:30 v/v) as mobile phase. The instrumental settings are flow rate of 1.0 ml/min, column temperature at 25±1°C, detector wavelength of 220 nm and the run time was 5 min. The retention time of the drug was 1.986 min. The developed method shows linearity over a range of 5-100 μg/ml of bosentan with correlation coefficient of 0.9991. The relative standard deviation is less than 1.5%. The proposed method was found to be suitable and accurate for quantitative determination of bosentan in pharmaceutical dosage forms

Application of Stability Indicating HPLC Method with UV Detector to the Analysis of Rivaroxaban in Bulk and Tablet Dosage Form

Abstract: A simple and sensitive stability indicating HPLC method is developed for the quantification of rivaroxaban in bulk and tablet dosage form. Chromatographic separation was achieved on an ACE-Ciano column (250 mm x 4.6 mm, 5 μm particle size). The mobile phase consists of 0.1M sodium acetate and methanol (60:40 v/v) and was delivered at a flow rate of 1 mL/min. A UV detector was used for the detection. The rivaroxaban was subjected to stress conditions for the assessment of the stability-indicating nature of the method. The method was validated as per ICH guidelines. The linearity is obtained in the range of 1-120 μg/mL. The limit of detection and quantification values is 0.194 μg/mL and 0.648 μg/mL respectively. The intra and inter-day %RSD values were below 1%. Intra and inter-day accuracies were within 100.10% and 100.40%, respectively. Degradation products resulting from the stress studies have no interfere with the detection of rivaroxaban. The average recovery of rivaroxaban in tablet dosage form was 99.74% with %RSD of 0.421%. The developed method was proved adequate for quantitative determination of rivaroxiban in presence of its degradation products

Simple and sensitive spectrophotometric methods for the analysis of mesalamine in bulk and tablet dosage forms

Three simple, sensitive, economical and reproducible spectrophotometric methods (A, B and C) are described for determination of mesalamine in pure drug as well as in tablet dosage forms. Method A is based on the reduction of tungstate and/or molybdate in Folin Ciocalteu's reagent; method B describes the reaction between the diazotized drug and α-naphthol and method C is based on the reaction of the drug with vanillin, in acidic medium. Under optimum conditions, mesalamine could be quantified in the concentration ranges, 1-30, 1-15 and 2-30 µg mL-1 by method A, B and C, respectively. All the methods have been applied to the determination of mesalamine in tablet dosage forms. Results of analysis are validated statistically

Extractive Spectrophotometric Determination of Ambrisentan

Purpose: Ambrisentan (ABS) is an antihypertensive drug used in the treatment of pulmonary atrial hypertension. The survey of literature for ABS revealed only two spectrophotometric methods for its quantification. The reported methods lack the sensitivity. This study is aimed at developing two sensitive extractive spectrophotometricmethods for the determination of ABS in bulk and in tablets. Methods: The proposed methods are based on the formation of colored chloroform extractable ion-pair complexes of ABS with methylene blue (MB method) and safranine O (SO method) in buffered solution at pH 9.8. The extracted complexes showed maximum absorbance at 525 and 515 nm for methylene blue and safranine O, respectively. Results: In both themethods, the calibration curve was linear from 1–15 μg mL−1 of drug. Apparent molar absorpitivities were 1.7911 x 105, 2.3272 x 105 L mol−1 cm−1; Sandell’s sensitivities were 0.0215, 0.0162 μg cm-2; LOD were 0.182, 0.175 μg mL−1; LOQ were 0.551, 0.531 μg mL−1 for methods MB and SO, respectively. The relative standard deviation and percent recovery ranged from 0.206–1.310% and 99.0–101.5%, respectively.Conclusion: The results demonstrate that the proposed methods are sensitive, precise, accurate and inexpensive. These methods can easily be used for the assay of ABS in quality control laboratories

Quantification of narcoleptic drug, Modafinil, by high performance liquid chromatographic method

A stability indicating HPLC method was developed and validated for modafinil quantification in bulk and tablet dosage forms. Aligent zorebax SB C18 analytical column (250 mm x 4.6 mm, 5 μm particle size) was used with mobile phase consisting of 0.1 M sodium dihydrogen phosphate and methanol in ratio 60:40 (v/v), flow-rate 1.0 ml/min, UV-detection at 230 nm and controlled temperature at 30°C. The linearity was found in the concentration range of 5-150 μg/ml. The method was validated as per the ICH guidelines. The drug was exposed to acidic, basic, oxidation, photo degradation and dry heat conditions. As the developed method can efficiently separate the modafinil from its degradation products, it can be employed as stability-indicating method.Key words: Modafinil, stability indicating HPLC, method development, validation, tablet dosage form

Studies on phytochemical and antibacterial activity of methanol, ethanol and acetone extracts of Grewia orientalis leaves

Three solvent extracts (methanol, ethanol and acetone) of Grewia orientalis leaves were screened for potential antibacterial activity against Escherichia coli, Bacillus substilis, Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae and Bacillus thuringienis. The agar disk diffusion method using filter paper disks was used to study the antibacterial activity of Grewia orientalis leaf extracts against 6 microbial strains. All the three extracts did not exert any inhibitory action on Bacillus thuringienis. The highest antibacterial potentials were observed for the acetone extract, followed by methanol and ethanol extracts. The Minimum Inhibitory Concentration (MIC) of the plant extracts were ranging from 50 to 250 μg/ml. The preliminary phytochemical screening of extracts was carried out for major phytochemical derivatives in Grewia orientalis

Use of electrophilic coupling reagents, 3-methyl-2-benzothiazolinone hydrazone hydrochloride and 4-amino antipyrine, for the spectrophotometric analysis of vardenafil in tablet dosage forms

Two new spectrophotometric methods (MBTH and AP) are developed for the determination of vardenafil in bulk and in tablet dosage forms. The MBTH method involves oxidative coupling of vardenafil with 3-methyl-2-benzothiazolinone hydrazone hydrochloride in presence of ferric chloride in acidic medium, yielding green colored chromogen with absorption maxima at 625 nm. The AP method is based on the oxidation of 4-aminoantipyrine by potassium periodate, which subsequently couples with vardenafil in an alkaline medium to form a red colored product having absorption maxima at 530 nm. The absorbance concentration graphs were rectilinear over the range of 4-40 μg/ml for MBTH method and 4-60 μg/ml for AP method. The developed methods were fully validated as per the guidelines prescribed by ICH. The application of the proposed methods in the determination of vardenafil in their commercial tablet dosage forms was successful showing good percentage recoveries.Key words: vardenafil, electrophilic coupling agent, MBTH, aminoantipyrine, analysis