Direct Injection Analysis of Diuretic and Anti-Inflammatory Drugs on a Shielded Hydrophobic Phase Column

Abstract

A shielded hydrophobic phase (SHP) column was used for the direct injection analysis of drugs from serum. Gradient elution gave the best separation; however, and isocratic separation is possible. The mobile phase pH was found to play a major role in the separation; ionic strength had a lesser influence. Quantitation of the drugs of interest was possible over several orders of magnitude. Inter- and intra-day recoveries showed values near 100%. A drug-containing serum sample was analyzed, using the described method, and the results were compared to a related liquid chromatographic method.