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  • Author or Editor: S. Joshi x
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Summary

Enantiomeric resolution of two commonly used β-blockers, namely, (±)-propranolol and (±)-atenolol, has been achieved on silica gel layers which were bulkimpregnated with β-cyclodextrin. Solvent systems DMF-ethyl acetate-butanol (3:2:5, υ/υ) and butanol-acetic acid-ethyl acetate-ammonia (5:2:2:0.5, υ/υ) successfully resolved the enantiomers of (±)-propranolol and (±)-atenolol, respectively. The spots were located with iodine vapor. The effects of concentration of the chiral selector and mobile phase variation were also studied.

Open access

Summary

A simple, reversed-phase HPLC method has been developed for rapid, simultaneous quantification of phenylephrine hydrochloride, guaiphenesin, ambroxol hydrochloride, and salbutamol (as salbutamol sulphate) in a commercial cough-cold liquid formulation. The compounds were separated on a 250 mm × 4.6 mm C8 column with a gradient prepared from pH 3.0 phosphate buffer and 1:1 methanol-acetonitrile as mobile phase at a flow rate of 1.0 mL min−1. Elution of the analytes was achieved in less than 15 min. Detection was by UV absorbance at 273 nm for phenylephrine hydrochloride and guaiphenesin and 225 nm for ambroxol hydrochloride and salbutamol. Percentage recovery and RSD were, respectively, 100.09% and 0.22% for phenylephrine hydrochloride, 100.43% and 0.50% for guaiphenesin, 100.91% and 0.70% for ambroxol hydrochloride, and 100.54% and 0.55% for salbutamol. The components of the syrup formulation were quantified on the basis of the peak areas obtained from freshly prepared standard solutions. The method was validated in accordance with ICH guidelines.

Open access

Summary

A simple, rapid, precise, and accurate, stability-indicating reversed phase high performance liquid chromatographic method was developed and validated for simultaneous determination of metformin HCl and repaglinide. The chromatographic separation was achieved on YMC Pack AM ODS (5 μm, 250 mm length × 4.6 mm i.d.) column at a detector wavelength of 210 nm, using an isocratic mobile phase consisting of methanol and 10 mM potassium dihydrogen phosphate buffer (pH 2.5) in a ratio of 70:30 v/v at a flow rate of 1 mL min−1. The retention times for metformin and repaglinide were found to be 2.6 and 11.3 min, respectively. The drugs were exposed to thermal, photolytic, hydrolytic, and oxidative stress conditions, and the stressed samples were analyzed by the proposed method. Validation of the method was carried out as per International Conference on Harmonization (ICH) guidelines. Linearity was established for metformin and repaglinide in the range of 5–200 μg mL−1 and 1–200 μg mL−1, respectively. The limits of detection were 0.3 μg mL−1 and 0.13 μg mL−1 for metformin and repaglinide, respectively. The method was found to be specific and stability-indicating as no interfering peaks of degradants and excipients were observed. The proposed method is hence suitable for application in quality-control laboratories for quantitative analysis of both the drugs individually and in combination, since it is simple and rapid with good accuracy and precision.

Open access