Nighat Shafi

Development of a RP-HPLC method for the simultaneous analysis of diltiazem and statin: Application in pharmaceuticals and human serum

High-performance liquid chromatographic (HPLC) method has been developed and validated for the simultaneous determination of diltiazem and statins in raw materials, their pharmaceutical formulations and human serum. In HPLC, diltiazem and statins are chromatographed using acetonitrile–water (85:15 v/v, pH 2.6 ± 0.02) as the mobile phase at a flow rate of 1.0 mL min−1 at ambient temperature. The separation is carried out on a Hiber®, 250-4.6 RP-18 column, equipped with a UV/visible detector at 230 nm. All the statins eluted at a different retention time and each showed good resolution from diltiazem. The method has been successfully applied to pharmaceutical formulations because no chromatographic interferences from the tablet excipients are found. The linearity is found to be in the range 0.625–20 μg mL−1. The suitability of the method for the quantitative determination of the drugs is proven by validation in accordance with the requirements laid down by the International Conference on Harmonization (ICH) guidelines. The validation results, together with statistical treatment of the data, demonstrated the reliability of this method.

Development of New Method for Simultaneous Analysis of Piracetam and Levetiracetam in Pharmaceuticals and Biological Fluids: Application in Stability Studies

RP-HPLC ultraviolet detection simultaneous quantification of piracetam and levetiracetam has been developed and validated. The chromatography was obtained on a Nucleosil C18 column of 25 cm × 0.46 cm, 10 μm, dimension. The mobile phase was a (70 : 30 v/v) mixture of 0.1 g/L of triethylamine and acetonitrile. Smooth flow of mobile phase at 1 mL/min was set and 205 nm wavelength was selected. Results were evaluated through statistical parameters which qualify the method reproducibility and selectivity for the quantification of piracetam, levetiracetam, and their impurities hence proving stability-indicating properties. The proposed method is significantly important, permitting the separation of the main constituent piracetam from levetiracetam. Linear behavior was observed between 20 ng/mL and 10000 ng/mL for both drugs. The proposed method was checked in bulk drugs, dosage formulations, physiological condition, and clinical investigations and excellent outcome was witnessed.

A RP-HPLC METHOD FOR THE SIMULTANEOUS DETERMINATION OF DILTIAZEM AND QUINOLONES IN BULK, FORMULATIONS AND HUMAN SERUM

High Performance Liquid Chromatographic method was developed and applied for the simultaneous determination of diltiazem and fluoroquinolones in bulk, pharmaceutical formulations and human serum in presence of caffeine as internal standard. A Hiber®, RP-18 column was used with mobile phase consisting of acetonitrile:methanol:water (30:20:50 v/v, pH 3.6) and quantitative evaluation was performed at 230 nm. Suitability of this method for the quantitative determination of the drugs was proved by validation in accordance with the requirements laid down by International Conference on Harmonization (ICH) guidelines.The method was selective, precise, accurate and can be used for routine analysis of pharmaceutical preparations, quality control and clinical laboratories.

Novel HPLC method for quantitative determination of cefazolin sodium in pharmaceutical formulations

This paper reports a validated high-performance liquid chromatography method which is rapid, highly specific, and accurate for determination of cefazolin sodium in injec table pharmaceutical formulations. Separation was carried out using a Hibar ® µBondapak ® C 18 column with a mobile phase consisting of an acetonitrile to monobasic sodium phosphate buffer ratio of 17:83 and a flow rate of 1.0 mL per minute, and monitoring at a wavelength of 254 nm. The calibration curve was linear, with a correlation coefficient .0.9995 in the range of 5-100 µg/mL. Drug recovery was 98.35%-100.86%, with a limit of detection of 12.92 ng/mL and a limit of quantification of 43.09 ng/mL. The drug was subjected to stress conditions of hydrolysis (acid, base, oxidation, and thermal degradation), where maximum degradation was observed. Forced degradation studies confirmed stability indicating power of this method, which was validated in accordance with International Conference on Harmonization guidelines and used successfully to quantify the amounts of cefazolin sodium in bulk injectable formulations

An Overview of Analytical Determination of Diltiazem, Cimetidine, Ranitidine, and Famotidine by UV Spectrophotometry and HPLC Technique

This review article recapitulates the analytical methods for the quantitative determinations of diltiazem and three H2 receptor antagonists (cimetidine, ranitidine, and famotidine) by one of the spectroscopic technique (UV spectrophotometery) and separation technique such as high-performance liquid chromatography (HPLC). The clinical and pharmaceutical analysis of these drugs requires effective analytical procedures for quality control, pharmaceutical dosage formulations, and biological fluids. An extensive survey of the literature published in various analytical and pharmaceutical chemistry-related journals has been compiled in its review. A synopsis of reported spectrophotometric and high-performance liquid chromatographic methods for individual drug is integrated. This appraisal illustrates that majority of the HPLC methods reviewed are based on the quantitative analysis of drugs in biological fluids, and they are appropriate for therapeutic drug monitoring purpose.

In vitro interaction studies of diltiazem with H2 receptor antagonists

Diltiazem is a well-known cardiovascular drug that is used clinically for the treatment of angina pectoris and hypertension. H2-receptor antagonists are used to treat gastroesophageal reflux, gastric and duodenal ulceration. In vitro interaction studies of diltiazem with H2-receptor antagonists (cimetidine, ranitidine, and famotidine) were investigated by using spectrophotometric and RP-HPLC techniques. The availability of diltiazem was found to be influenced considerably in presence of H2-receptor antagonists. The effect of various dissolution mediums, simulating body environments with respect to pH on these interactions was examined to elucidate the mechanism of these interactions. Moreover, diltiazem-H2 receptor complexes were synthesized to confirm the interaction of these drugs. The complexes formed were then characterized by IR spectroscopy and verified by computational molecular modeling.