A simple, sensitive isocratic method for the detection and quantification of ciprofloxacin in plasma and urine has been developed. The assay consisted of reversed-phase HPLC with ultraviolet detection. Plasma proteins were removed by a fast and efficient procedure. For the urine samples, the only required sample preparation was dilution. Separation was achieved on a C18 reversed-phase column. T...

Optimization of sample pre-treatment. Complete removal of cellular and further solid sample constituents, precipitation and removal of proteins, precipitation and removal of cholesterol from the blood sample and quantitative extraction of the analytes tryptophan, phenol, p-cresol and cholic acid in the diluted blood plasma phase. Step III: Combination and conversion of both isocratic HPLC/DAD/M...

A simple and rapid method of reversed-phase ion-pair high-performance liquid chromatography (HPLC) with UV-detection on a common C(18) column in an isocratic mode with the addition of tetrabutylammonium phosphate for the separation of polyprenyl phosphate oligomerhomologues has been developed. The method was successfully applied to assay the composition of polyprenyl phosphates obtained from p...

As a part of preliminary studies, the possibility quantitative oxidation aldehydes to carboxylic acids and their determination by isocratic ion chromatography with conductometric detection has been tested. A methodology for simultaneous separation inorganic anions (F-, Cl-, NO2-, Br-, NO3-, PO43-, SO42-) (formate, acetate oxalate) using conductivity have developed validated. Six anion-exchange ...

This paper describes potential applications of computer-assisted chemometrics in method development in liquid chromatography. These include modeling of retention (isocratic, gradient, molecular modeling, artificial neural networks), assessment of separation (peak capacity), single and multiple objective optimization approach, advanced optimization algorithms (genetic algorithms, simulated annea...

Separation of a mixture of the main cytokinins occurring naturally in plant tissues was achieved by high pressure liquid chromatography using insoluble polyvinylpyrrolidone as the solid support. The separation of each cytokinin was first assessed over a range of salt and l-butanol concentrations and pH using a mixture of borate buffer and l-butanol as the mobile phase to determine the condition...

Determination of trace amounts of bisphenol A (BPA) may cause problems mainly related to the presence of BPA in solvents (even in LC-MS grade), laboratory vessels, and plastic equipment used for sample preparation. Variable and sometimes significant amounts of BPA present in the background cause problems in obtaining good repeatability of measurements at the ultra-trace levels. Such observation...

Hydrophilic interaction chromatography (HILIC) is a liquid chromatographic separation mechanism commonly used for polar biological molecules. The use of enhanced-fluidity liquid chromatography (EFLC) with mixtures of methanol/water/carbon dioxide is compared to acetonitrile/water mobile phases for the separation of nucleosides and nucleotides under HILIC conditions. Enhanced-fluidity liquid chr...

A simple, sensitive isocratic reversed-phase HPLC method for detecting and quantifying ciprofloxacin in pharmaceutical dosage forms has been developed validated according to ICH guidelines. In the method, separation was achieved on a C18 column with mobile phase acetonitrile-water at ratio of (80:20). The pH adjusted 2.7 using 85% phosphoric acid ultraviolet detection 275.0 nm. flow rate 1.7 mL...

The combination of Atorvastatin and Losartan was used in the management of Hypertension. The present work was focused on the development of RP-HPLC method for the estimation of Atorvastatin and Losartan in binary mixtures by internal standard method. The separation was performed on LUNA C18 column at 238 nm by isocratic elution using Telmisartan as internal standard. Methanol and phosphate buff...