Simple RP-HPLC Method for Estimation of Furosemide, Carbamazepine, Diazepam and Carvedilol in Bulk and Pharmaceutical Dosage Forms

A simple reverse-phase high performance liquid chromatographic method for the simultaneous analysis (separation and quantification) of furosemide (FURO), carbamazepine (CARB), diazepam (DIAZ) and carvedilol (CARV) has been developed and validated. The method was carried out on a NUCLEODUR® 100-5 C18ec column (250 x 4.6 mm, i. d.5µm), with a mobile phase comprising of acetonitrile: deionized water (50: 50 v/v, pH adjusted to 3.6 ±0.05 with acetic acid) at a flow rate 1.5 mL.min-1 and the quantification was achieved at 226 nm. The retention times of FURO, CARB, DIAZ and CARV were found to be 1.90 min, 2.79 min, 5.39 min and 9.56 min respectively. The method was validated in terms of linearity, accuracy, precision, limit of detection and limit of quantitation. The developed method was successfully applied for the estimation of furosemide, carbamazepine, diazepam and carvedilol in bulk and in pharmaceutical dosage forms. Keywords: RP-HPLC, Furosemide, Carbamazepine, Diazepam and Carvedilo

Spectrophotometric-Assisted Chemometric Method for the Simultaneous Analysis of Furosemide, Carbamazepine, Diazepam, and Carvedilol in Their Bulk and Marketed Formulation

Simultaneous determination of Furosemide, Carbamazepine, Diazepam, and Carvedilol in bulk and pharmaceutical formulation using the partial least squares regression (PLS-1 and PLS-2) is described in this study. The two methods were successfully applied to estimate the four drugs in their quaternary mixture using UV spectral data of 84synthetic mixtures in the range of 200-350nm with the intervals ∆λ=0.5nm. The linear concentration range were 1-20 µg.mL-1 for all, with correlation coefficient (R2) and root mean squares error for the calibration (RMSE) for FURO, CARB, DIAZ, and CARV were 0.9996, 0.9998, 0.9997, 0.9997, and 0.1128, 0.1292, 0.1868,0.1562 respectively for PLS-1, and for PLS-2 were 0.9995, 0.9999, 0.9997, 0.9998, and 0.1127, 0.1205, 0.1691, and 0.1686 respectively. Satisfactory results were achieved with applying PLS-1 and PLS-2 in the determination of the cited drugs in their pharmaceutical formulations and a good agreement was found between the proposed methods. Keywords: PLS, spectrophotometry, furosemide, carbamazepine, diazepam, and carvedilo