The results are given in Table 5. The typical chromatogram of Metronidazole and Norfloxacin shown in Fig. 3, it was found that the retention times were 2.39 and 3.45 min which are very short retention times than earlier reported method (7.5 & 9.9 min). The mobile phase composition at a ratio

of 82:18 (v/v) of buffer pH 4.0 and acetonitrile was found to be most suitable to obtain peaks well defined selleck chemical and free from tailing. Here the organic phase is 18% where as it is 30% in previous method. So the proposed method is cost effective. A good linear relationship (r = 0.999) was observed between the concentration ranges 75, 100, 125, 150, 175 μg/ml of Metronidazole and 60, 80, 100, 120, 140 μg/ml of Norfloxacin. Low values of Z-VAD-FMK molecular weight S.D are indicative of high precision of the method. The assay of Nor-metrogyl tablets was found to be 99.4% and 100% for Metronidazole and Norfloxacin respectively. From the recovery studies, it was found that 101.94% of Metronidazole and 99.9% of Norfloxacin recovered which indicates high accuracy of the method. The results of LOD and LOQ indicate that the method is reliable and also the method shows good resolution with short separation time for analysis. The forced degradation studies were also carried out as per ICH guidelines. There was complete separation

of degradation peaks and analyte peaks, which demonstrate the specificity of assay method for estimation of Metronidazole and Norfloxacin in the presence of its degradation products; it can be employed as a stability indicating one. The proposed HPLC method is stability indicating one, cost effective and less time consuming. Also satisfactory results were obtained for all validation parameters. Hence the proposed method is rapid, simple, economic, accurate and robust. Moreover the degradated peaks were well resolved from analyte peaks. So the developed method may be used for analysis of stability samples of Metronidazole and Norfloxacin in quality control laboratory. All authors

have none to declare. “
“Eprosartan mesylate (EPM) is chemically monomethane sulfonate of (E)-2-butyl-1-(p-carboxybenzyl)-α-2-thienylmethylimidazole-5-acrylicacid Thymidine kinase (Fig. 1) is a new antihypertensive agent as an angiotension II receptor antagonist that is highly selective to elicit a higher reduction in systolic blood pressure than other antihypertensive drugs.1 and 2 The drug acts on the renin-angiotension system in two ways to decrease total peripheral resistance. First, it blocks the binding of angiotension II to AT1 receptors in vascular smooth muscle, causing vascular dilatation. Second, it inhibits sympathetic nor epinephrine production, further reducing blood pressure.3 and 4 A very few spectrophotometric methods5, 6 and 7 and HPLC, LC–MS methods in different matrices have been reported for the determination of Eprosartan in literature.