Background:The main objective was to develop and validate the UV-spectrophotometric method for the estimation of terbinafine hydrochloride in bulk and pharmaceutical formulations as per ICH guidelinesMaterials and Methods:A simple, rapid, accurate, and economical UV-spectrophotometric method has been developed for the estimation of terbinafine hydrochloride from bulk and pharmaceutical formulation.Results:The λmax of terbinafine hydrochloride in water was found to be 283 nm. The drug follows linearity in the concentration range 5–30 μg/ml with a correlation coefficient value of 0.999. The proposed method was applied to pharmaceutical formulation and % amount of drug. estimated was 99.19% and was found to be in good agreement with the label claim. The accuracy of the method was checked by recovery experiment performed at three different levels, i.e., 80%, 100%, and 120%. The % recovery was found to be in the range of 98.54– 99.98%. The low values of % RSD are indicative of the accuracy and reproducibility of the method. The precision of the method was studied as an intraday; interday variations, and repeatability. The % RSD value < 2 indicates that the method is precise. Ruggedness of the proposed method was studied with the help of two analysts.Conclusion:The above method was a rapid tool for routine analysis of terbinafine hydrochloride in the bulk and in the pharmaceutical dosage form.

BackgroundThe discovery of clinically relevant inhibitors of HIV-RT for antiviral therapy has proven to be a challenging task. To identify novel and potent HIV-RT inhibitors, the quantitative structure–activity relationship (QSAR) approach became very useful and largely widespread technique forligand-based drug design.MethodsWe perform the two- and three-dimensional (2D and 3D) QSAR studies of a series of 1,2,3-thiadiazole thioacetanilides analogues to elucidate the structural properties required for HIV-RT inhibitory activity.ResultsThe 2D-QSAR studies were performed using multiple linear regression method, giving r2 = 0.97 and q2 = 0.94. The 3D-QSAR studies were performed using the stepwise variable selection k-nearest neighbor molecular field analysis approach; a leave-one-out cross-validated correlation coefficient q2 = 0.89 and a non-cross-validated correlation coefficient r2 = 0.97 were obtained. Docking analysis suggests that the new series have comparable binding affinity with the standard compounds.ConclusionsThis approach showed that hydrophobic and electrostatic effects dominantly determine binding affinities which will further useful for development of new NNRTIs.

A simple, specific, accurate and precise stability-indicating reversed-phase high-performance liquid chromatographic method was developed for simultaneous estimation of olmesartan medoxomile (OLME), amlodipine besylate (AMLO) and hydrochlorothiazide (HCTZ) in tablet dosage form. The method was developed using an RP C18 base deactivated silica column (250 × 4.6 mm, 5 µm) with a mobile phase consisting of triethylamine (pH 3.0) adjusted with orthophosphoric acid (A) and acetonitrile (B), with a timed gradient program of T/%B: 0/30, 7/70, 8/30, 10/30 with a flow rate of 1.4 mL/min. Ultraviolet detection was used at 236 nm. The retention times for OLME, AMLO and HCTZ were found to be 6.72, 4.28 and 2.30, respectively. The proposed method was validated for precision, accuracy, linearity, range, robustness, ruggedness and force degradation study. The calibration curves of OLME, AMLO and HCTZ were linear over the range of 50-150, 12.5-37.5 and 31-93 µg/mL, respectively. The method was found to be sensitive. The limits of detection of OLME, AMLO and HCTZ were determined 0.19, 0.16 and 0.22 µg/mL and limits of quantification of OLME, AMLO and HCTZ were determined 0.57, 0.49 and 0.66, respectively. Forced degradation study was performed according to International Conference on Harmonization guidelines.

Aim:A simple, selective, precise, and stability-indicating high-performance thin-layer chromatographic (HPTLC) method for analysis of cefpodoxime proxetil both in bulk and in pharmaceutical formulation has been developed and validated.Materials and Methods:The method employed HPTLC aluminum plates precoated with silica gel 60 RP-18 F254 as the stationary phase. The solvent system consisted of toluene:methanol:chloroform (4:2:4 v/v). The system was found to give compact spot for cefpodoxime proxetil (Rf value of 0.55 ± 0.02). Densitometric analysis of cefpodoxime proxetil was carried out in the absorbance mode at 289 nm.Results:The linear regression analysis data for the calibration plots showed good linear relationship, with r2 = 0.998 ± 0.0015 with respect to peak area in the concentration range of 100–600 ng per spot. The mean value±SD of slope and intercept were 3.38 ± 1.47 and 986.9 ± 108.78 with respect to peak area. The method was validated for precision, recovery, and robustness. The limits of detection and quantification were 3.99 and 12.39 ng per spot, respectively. Cefpodoxime proxetil was subjected to acid and alkali hydrolysis, oxidation, and thermal degradation. The drug undergoes degradation under acidic and basic conditions, indicating that the drug is susceptible to both acid and base. The degraded product was well resolved from the pure drug, with significantly different Rf value. Statistical analysis proves that the method is repeatable, selective, and accurate for the estimation of the investigated drug.Conclusion:The proposed HPTLC method can be applied for identification and quantitative determination of cefpodoxime proxetil in both bulk drug and pharmaceutical formulation.

Olmesartan Medoxomil (OLME) belongs to a group of angiotensin II receptor blockers used as an antihypertensive agent and is currently being used for prevention of Hypertension. This paper describes the Validation and development of stability indicating RP-HPLC method for the determination of OLME in the presence of its degradation products generated from forced degradation study and characterization of degradation product (impurity). The assay involved gradient elution of OLME on An LC GC BDS C18 column (250 × 4.5mm, 5-μm particle size) was employed for loading the sample. The mobile phase A consists of 7 ml Triethylamine in 1000 ml water (pH adjusted to 3.0 with orthophosphoric acid) and B contains acetonitrile. Quantification was achieved with photodiode array detection at 257 nm. The chromatographic separation was obtained with a retention time of 6.72 min, and the method was linear in the range 50-150 µg/ml. The method was validated according to the ICH guidelines with respect to linearity, precision, accuracy, limit of detection (LOD), limit of quantification (LOQ), specificity and robustness. Impurity found in stressed and stability studies of Olmesartan Medoxomil in both drug substance and drug product are described. This degradation product is identified as 1-(biphenyl-4-ylmethyl)-1H-imidazole-5-carboxylic acid. An Alkaline degradation pathway of Olmesartan medoxomil, for the formation of this degradation product, has been proposed and degradation product was characterized