DEVELOPMENT AND VALIDATION OF RPLC METHODS FOR PURITY CONTROL OF SELECTED ANTIBIOTICS

nrpages: 143status: publishe

Development and validation of a liquid chromatographic method for purity control of clopidogrel–acetylsalicylic acid in combined oral dosage forms

A reversed phase liquid chromatographic method with UV detection for the simultaneous determination of clopidogrel and acetylsalicylic acid and their related substances in combined oral formulations was developed and validated. Good separation was achieved on a Luna C18 column (150 mm × 4.6 mm, 3 μm) using gradient elution at a flow rate of 1 mL/min and a column temperature of 35 °C. UV detection was performed at 220 nm. The validation was performed according to the ICH guidelines. The method proved to be specific, sensitive (LOQ=0.975 μg/mL and 0.0384 μg/mL for clopidogrel and acetylsalicylic acid, respectively), linear in the concentration range from LOQ to 325 μg/mL for clopidogrel and from LOQ to 650 μg/mL for acetylsalicylic acid, precise (RSD values for intermediate precision <1%) and accurate with mean recovery values of 100.7% and 100.2% for clopidogrel and acetylsalicylic acid, respectively. Moreover, the solution stability and method robustness were examined. The method gives satisfactory separation of impurities of clopidogrel and acetylsalicylic acid and so it is suitable for quantification of the related substances as well as for the assay of the actives.status: publishe

Kinetic Performance Comparison of Fully and Superficially Porous Particles with a Particle Size of 5 µm: Intrinsic Evaluation and Application to the Impurity Analysis of Griseofulvin

After the great commercial success of sub- 3 µm superficially porous particles, vendors are now also starting to commercialize 5 µm superficially porous particles, as an alternative to their fully porous counterparts which are routinely used in pharmaceutical analysis. In this study, the performance of 5 µm superficially porous particles was compared to that of fully porous 5 µm particles in terms of efficiency, separation performance and loadability on a conventional HPLC instrument. Van Deemter and kinetic plots were first used to evaluate the efficiency and performance of both particle types using alkylphenones as a test mixture. The van Deemter and kinetic plots showed that the superficially porous particles provide a superior kinetic performance compared to the fully porous particles over the entire relevant range of separation conditions, when both support types were evaluated at the same operating pressure. The same observations were made both for isocratic and gradient analysis. The superior performance was further demonstrated for the separation of a pharmaceutical compound (griseofulvin) and its impurities, where a gain in analysis time of around 2 could be obtained using the superficially porous particles. Finally, both particle types were evaluated in terms of loadability by plotting the resolution of the active pharmaceutical ingredient and its closest impurity as a function of the signal-to-noise ratio obtained for the smallest impurity. It was demonstrated that the superficially porous particles show better separation performance for griseofulvin and its impurities without significantly compromising sensitivity due to loadability issues in comparison with their fully porous counterparts. Moreover these columns can be used on conventional equipment without modifications to obtain a significant improvement in analysis time.publisher: Elsevier articletitle: Kinetic performance comparison of fully and superficially porous particles with a particle size of 5µm: Intrinsic evaluation and application to the impurity analysis of griseofulvin journaltitle: Talanta articlelink: http://dx.doi.org/10.1016/j.talanta.2014.01.050 content_type: article copyright: Copyright © 2014 Elsevier B.V. All rights reserved.status: publishe

Development and validation of a reversed-phase liquid chromatographic method for analysis of demeclocycline and related impurities

A simple, robust, and rapid reversedphase high-performance liquid chromatographic method for the analysis of demeclocycline and its impurities is described. Chromatographic separations were achieved on a Symmetry Shield RP8 (75 mm × 4.6 mm, 3.5 μm) column kept at 40°C. The mobile phase was a gradient mixture of acetonitrile, 0.06 M sodium edetate (pH 7.5), 0.06 M tetrapropylammonium hydrogen sulphate (pH 7.5) and water, A (2:35:35:28 v/v/v/v) and B (30:35:35:0 v/v/v/v) pumped at a flow rate of 1 mL/min. UV detection was performed at 280 nm. The developed method was validated according to the ICH guidelines for specificity, limit of detection, limit of quantification, linearity, precision, and robustness. An experimental design was applied for robustness study. Results show that the peak shape, chromatographic resolution between the impurities, and the total analysis time are satisfactory and better than previous methods. The method has been applied for the analysis of commercial demeclocycline bulk samples available on the market.status: publishe

Hydrophilic interaction chromatography (HILIC) in the analysis of antibiotics

This paper presents a general overview of the application of hydrophilic interaction chromatography (HILIC) in the analysis of antibiotics in different sample matrices including pharmaceutical, plasma, serum, fermentation broths, environmental water, animal origin, plant origin, etc. Specific applications of HILIC for analysis of aminoglycosides, β-lactams, tetracyclines and other antibiotics are reviewed. HILIC can be used as a valuable alternative LC mode for separating small polar compounds. Polar samples usually show good solubility in the mobile phase containing some water used in HILIC, which overcomes the drawbacks of the poor solubility often encountered in normal phase LC. HILIC is suitable for analyzing compounds in complex systems that elute near the void in reversed-phase chromatography. Ion-pair reagents are not required in HILIC which makes it convenient to couple with MS hence its increased popularity in recent years. In this review, the retention mechanism in HILIC is briefly discussed and a list of important applications is provided including main experimental conditions and a brief summary of the results. The references provide a comprehensive overview and insight into the application of HILIC in antibiotics analysis.status: publishe

LC Assay for a HIV Tablet Containing Emtricitabine, Tenofovir Disoproxil Fumarate and Rilpivirine

A liquid chromatographic method with UV detection was developed for the assay of a tablet for HIV (human immunodeficiency virus) treatment containing three active components, which are emtricitabine, tenofovir disoproxil fumarate and rilpivirine. A Hypersil BDS-C18 column was used as stationary phase and the assay was performed with gradient elution using mobile phases containing acetonitrile, 0.2 M potassium dihydrogen phosphate and water. Dimethyl sulfoxide-distilled water (1:1) was used as solvent for the active components. The method proved to be selective, linear, repeatable, sensitive and easy to perform.status: publishe