Sharif Digital Repository

A rapid, simple and efficient liquid chromatographic method was developed for simultaneous determination of three active ingredients namely, chlorpheniramine maleate, phenylephrine hydrochloride and guaifenesin along with sodium benzoate preservative common cold medications (syrups) and the method was validated based on the International Conference on Harmonization (ICH) and United State Pharmacopeia (USP) guidelines. Separation of the analytes was achieved within 15 min on a nucleosil gravity phenyl column in a single run with a mobile phase consisting of methanol: buffer mixture (15:85 v/v) at room temperature, in isocratic mode with flow rate of 0.8 mL min−1. A comprehensive study on... 

This paper focuses on characterization of the components of Iranian rosemary essential oil using gas chromatography-mass spectrometry (GC-MS). Multivariate curve resolution (MCR) approach was used to overcome the problem of background, baseline offset and overlapping/embedded peaks in GC-MS. The analysis of GC-MS data revealed that sixty eight components exist in the rosemary essential oil. However, with the help of MCR this number was extended to ninety nine components with concentrations higher than 0.01%, which accounts for 98.23% of the total relative content of the rosemary essential oil. The most important constituents of the Iranian rosemary are 1,8-cineole (23.47%), α-pinene... 

Aims: The metabolism of phenanthrene and anthracene by a moderate thermophilic Nocardia otitidiscaviarum strain TSH1 was examined. Methods and Results: When strain TSH1 was grown in the presence of anthracene, four metabolites were identified as 1,2-dihydroxy-1,2-dihydroanthracene, 3-(2-carboxyvinyl)naphthalene-2-carboxylic acid, 2,3-dihydroxynaphthalene and benzoic acid using gas chromatography-mass spectrometry (GC-MS), reverse phase-high performance liquid chromatography (RP-HPLC) and thin-layer chromatography (TLC). Degradation studies with phenanthrene revealed 2,2′-diphenic acid, phthalic acid, 4-hydroxyphenylacetic acid, o-hydroxyphenylacetic acid, benzoic acid, a phenanthrene...