A simple, accurate, precise, sensitive and reproducible reverse phase high performance liquid chromatography method has been developed for the quantitative determination of etoricoxib in pharmaceutical dosage forms. The assay was performed on inertsil ODS-4 column as stationary phase. The mobile phase containing 0.01M sodium perchlorate monohydrate and acetonitrile in the ratio of 48:52 v/v. The detection of analyte performed by using UV detector at wavelength maxima 235 nm. The column oven temperature was maintained at 30º C. Percentage recovery found within the limit ranges 98.9-99.5%. The calibration curve was linear over the concentration range of 70-130% and correlation coefficient was found to be 0.99. Peak purity had passed in the sample solution for all degradation conditions, no interference from placebo observed under stressed conditions. Sample solution was found to be stable at 10ºC for about 21 hours. In dissolution study the method was linear over the concentration range of 20-120% and correlation coefficient was found to be 0.99. Percentage recovery was found to be 99.3-100.8%. Filter equivalency was found within the limits for both standard solutions. The method was further validated with respect to linearity, accuracy, precision and robustness according to ICH guidelines. The method was statistically evaluated and can be applied for routine control analysis of etoricoxib in tablet formulations.

Perindopril is chemically (2S, 3aS, 7aS)-1-[(S)-N-[(S)-1-carboxybutyl] alanyl] hexahydro-2-indolinecarboxylic acid 1-ethyl ester2. It is an angiotensin-converting-enzyme inhibitor (ACE inhibitor). In this method  measurement of absorbance at the wavelength of maximum absorptions of Perindopril using water as a solvent is done . The calibration curve was linear in concentration range of 12.5-200 µg/ml for Perindopril with correlation coefficient of 0.9991. The accuracy and precision of the method was determined and validated statically. The method showed good recovery with % RSD less than 2 and good reproducibility. Method was found to be rapid, specific, precise and accurate. This method can be successfully applied for the routine analysis of perindopril Accuracy of proposed method was confirmed by performing accuracy studies which showed the accepted results. Precision of proposed method was confirmed by performing intraday and inter day precision. The method for the determination of perindopril was validated according to ICH guidelines.

Amoxicillin is a potent bactericidal drug with activity against Gram-positive and Gram-negative bacteria. During the process development of amoxicillin, formation of various impurities was observed. Although, the structures and analytical procedures of these impurities have been already reported in the literature, surprisingly their synthesis was not accounted. In the present investigation, we have synthesized Amoxicillin impurity H namely (2R)-2-[(2,2-dimethylpropanoyl)amino]-2-(4-hydroxyphenyl) acetic acid.. The synthesized impurity has been characterized using FTIR, ¹H-NMR, Mass Spectrometry for m/z ratio and Elemental analysis.

A simple, reproducible and efficient reverse phase high performance liquid chromatographic method was developed for simultaneous determination of lisinopril(LSN) and amlodipine (AMD) in tablets. A column having 150 × 4.6 mm  in isocratic mode with mobile phase containing acetonitrile: phosphate buffer (55:45; adjusted to pH 3.0) was used. The flow rate was 0.6 ml/min and effluent was monitored at 216 nm. The retention time 8 (min) and linearity range (μg/ml) for LSN and AMD were and (20-60,10-30), respectively. The developed method was found to be accurate, precise and selective for simultaneous determination of LSNand AMD in tablets.

A multidisciplinary approach is required for analyzing essential oils. Along with analytical chemistry other branches like phytochemistry, organic synthetic chemistry and biochemistry is strongly required. In the last thirty years a huge process was in pipeline for calibrating instrumental sensitivity and selectivity improvement. The real big problem for phytochemistry is that the extracts contain a loarge number of compounds along with the essential oil in investigation. Extremely specific methods are required for qualitative and quantitative analysis.

Objective: To develop and subsequently validate a new simple and sensitive high performance thin layer chromatographic (HPTLC) method for estimation of Levocetirizine, Pseudoephedrine and Ambroxol simultaneously, from a bulk drug and combined dosage form. Method: The separation of drugs was carried out on Merck HPTLC aluminium sheets of silica gel 60 F₂₅₄ as stationary phase and the chromatogram was developed using Ethyl-acetate: methanol: ammonia (8: 1: 0.5 v/v/v) as the mobile phase. Result:  Levocetirizine, Pseudoephedrine and Ambroxol showed R_f values 0.1 ± 0.02, 0.39 ± 0.05, and 0.73 ± 0.05 respectively, when scanned densitometrically at 212 nm using Camag TLC Scanner. The described method was linear over a concentration range of 100 ng spot^-1 to 700 ng spot^-1, 600 ng spot^-1 to 4200 ng spot^-1 and 1200 ng spot^-1 to 8400 ng spot^-1 for the Levocetirizine, Pseudoephedrine and Ambroxol respectively. Results of analysis were validated according to International Conference on Harmonization ICH Q2B guidelines statistically, and by recovery studies. The limit of detection (LOD) for Levocetirizine, Pseudoephedrine and Ambroxol were found to be 25 ng spot^-1, 40 ng spot^-1 and 35 ng spot^-1 respectively. The limit of quantification (LOQ) were found to be 60 ng spot^-1, 87 ng spot^-1 and 71 ng spot^-1  for Levocetirizine, Pseudoephedrine and Ambroxol respectively. Conclusion: The results of the study showed that the proposed HPTLC method is simple, rapid, precise and accurate, which is useful for the routine determination of Levocetirizine, Pseudoephedrine and Ambroxol bulk drug and in its pharmaceutical dosage form.