No abstract

A novel generic reverse phase high performance liquid chromatography (RP‐HPLC) method is developed and validated for simultaneous determination of seven pharmaceutically active ingredients, namely, acetaminophen, dextromethorphan, doxylamine, phenylephrine, guaifenesin, caffeine and aspirin. All seven ingredients were quantified in soft gel, syrup and tablet formulations of the over‐the‐counter US‐marketed products, as per the guidelines of the International Conference on Harmonization. The separation was achieved in a 16 min run time on an Agilent Zorbax Phenyl column using a gradient method with two mobile phases. Mobile phase A was 0.15% trifluoro acetic acid in purified water and while mobile phase B was a mixture of acetonitrile and methanol (750:250 v/v) with 0.02% trifluoro acetic acid. The flow rate was 1.0 mL min−1 and injection volume was 10 μL. Detection was performed at 280 nm using a photodiode array detector. As part of the method validation, specificity, linearity, precision and recovery parameters were verified. The concentration and area relationships were linear (R2 > 0.999), over the concentration ranges 20–120 μg mL−1 for acetaminophen, 75–450 μg mL−1 for dextromethorphan, 31.25–187.5 μg mL−1 for doxylamine, 25–150 μg mL−1 for phenylephrine, 25–150 μg mL−1 for aspirin, 6.5–39 μg mL−1 for caffeine and 12–72 μg mL−1 for guaifenesin. The relative standard deviations for precision and intermediate precision were <1.5%. The proposed RP‐HPLC generic method is applicable for routine analysis of cold and cough over‐the‐counter products.

2-(2-Chloroethoxy)ethanol (CEE) belongs to the so-called cohort of concerns which were classified as highly potent mutagenic carcinogens by the World Health Organization. It is widely used in the synthesis of the essential anti-histamine drug hydroxyzine. In addition, it is used as a primary solvent in dyes, nitrocellulose, paints, inks and resins. Owing to its potential genotoxicity, an efficient liquid chromatographytandem mass spectrometry method was developed for the quantitative estimation of CEE traces in an active pharmaceutical ingredients and in tablet dosage forms of hydroxyzine-free base. The chromatographic separation was achieved on a C 18 column using a gradient elution mode with a binary solvent system (ammonium formate

We developed novel stability-indicating HPLC method for simultaneous estimation of 14 impurities in excedrin tablet, a formulation with a combination of acetaminophen, aspirin, and caffeine. In addition, a new impurity that was generated through degradation of aspirin at high temperatures during the accelerated stability conditions was positively identified and confirmed, using liquid chromatography-mass spectrometry technique. The HPLC method was optimized using the Inertsustain C 18 , 250 × 4.6 mm, 5.0 μm column, employing simple gradient method. Forced degradation studies were performed under acidic, basic, oxidative and thermal conditions to prove the scope and stability-indicating the nature of the method. The optimized method was validated as per the International Conference on Harmonization guidelines. The HPLC method showed linearity from LOQ concentration to 21 μg mL −1 . Precision and intermediate precision values were <5% RSD. The validated HPLC method is currently applied for the routine testing of excedrin tablet formulations in quality control laboratories.

Montelukast sodium (MLS) is a leukotriene receptor antagonist drug used in the treatment of asthma, bronchospasm, allergic rhinitis and urticaria. A reversed-phase high performance liquid chromatography method was developed to separate, identify and quantitative determination of MLS and its eight known organic impurities in tablet dosage form using a C 18 column and mobile phases consisting of a gradient mixture of pH 2.5 phosphate buffer and acetonitrile. The stability-indicating character of the developed method was proven using stress testing (1 M HCl at 80 C/30 min, 1 M NaOH at 80 C/30 min, H 2 O at 80 C/30 min, 3% H 2 O 2 at 25 C/1 min, dry heat at 105 C/10 h and UV-vis light/4 days) and was validated for specificity, quantitation limit, linearity, precision, accuracy and robustness. For MLS and its eight known impurities, the quantitation limits, linearity and recoveries were 0.015-0.03 μg/ml, correlation coefficient > 0.997 (R 2 > 0.995) and 85.5-107.0%, respectively. The developed chromatographic method is suitable for impurity profiling and also for assay determination of MLS in bulk drugs and pharmaceutical formulations. The mass values (m/z) of newly formed degradation products (DP1 and DP2) of montelukast sodium were identified using liquid chromatography-mass spectrometry.