Liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was used for simultaneous quantification of tolterodine and its metabolite 5-hydroxy methyl tolterodine in rat plasma. Tolterodine-d6 and 5-hydroxy methyl tolterodine-d14 were used as internal standards (IS). Chromatographic separation was performed on Ascentis Express RP amide (50 mm×4.6 mm, 2.7 μm) column with an isocratic mobil...

Resistant cells of Pseudomonas aeruginosa and a waterborne Pseudomonas sp. (strain Z-R) were able to multiply in nitrogen-free minimal salts solution containing various concentrations of commercially prepared, ammonium acetate-buffered benzalkonium chloride (CBC), a potent antimicrobial agent. As the CBC concentration increased, growth increased until a point was reached at which the extent of ...

An orthogonal L(36) (6)(5) test design was applied to select the optimum conditions for extracting resveratrols from grape berry skins and leaves. Solvent choice was the most important factor in the extraction of resveratrols, and mixed methanol and ethyl acetate [50:50 (v/v)] had much higher extraction efficiency than the other five solvents tested. For extracting resveratrols, 1g of berry ski...

A simple and specific liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry (LC-APCI-MS) assay method has been developed and fully validated for the simultaneous quantification of cefixime (CX) and clavulanic acid (CA) in human plasma. Analytes and internal standard were extracted from human plasma by a solid phase extraction technique using a Sam prep (3 mL, 100 mg) ...

A high throughput ultra pressure liquid chromatography-mass spectrometry (UPLC-MS/MS) method with good sensitivity and selectivity has been developed and validated for simultaneous quantification of esomeprazole, rabeprazole and levosulpiride in human plasma using lansoprazole as internal standard (IS). The extraction method based on liquid-liquid extraction technique was used to extract the an...

In this paper high-performance liquid chromatography with diode array UV detection (HPLC/DAD) after SPE sample pretreatment for simultaneous analysis of pharmaceuticals from three different classes: enrofloxacin, oxytetracycline and trimethoprim, has been developed, optimised and validated. The chromatographic separation was developed on spiked wellspring water samples and checked on model wast...

We describe a fluorometric method for determining zinc protoporphyrin, in which whole-blood specimens collected in heparin/ethylenediaminetetraacetate are prediluted with water, and zinc protoporphyrin is extracted into ethanol/ water (95/5 by voi). The resulting extract has a low absorbance (0.05) at the excitation wavelength (415 nm) of zinc protoporphyrin, and the extraction efficiency is ab...

The objective of this study was to describe an analytical validation of a simple, rapid, sensitive, and selective liquid chromatography (LC)-tandem mass spectrometry (MS-MS) method for quantification of metronidazole in human plasma samples from bioavailability studies. The plasma samples were pre-treated by liquid-liquid extraction (LLE) with ethyl acetate. Metronidazole and the internal stand...