Determination of a New Antiulcer Drug in Rat Blood Plasma by Liquid Chromatography–Mass Spectrometry.

Synthesis of an innovative drug 9-(2,5-dihydroxyphenyl)-2-(4-ethoxyphenyl)-2,3,7,8-tetrahydro-1H-pyrido[1,2-a]pyrazine-1,4(6H)-dione (PPI) for the treatment of peptic ulcer with a new mechanism of action has necessitated the pharmacokinetics study of the substance in the blood plasma and investigation of its absorption and elimination processes. This paper describes the development and validation of a technique for the quantitative determination of new compound PPI in rat blood plasma by HPLC/MS. The method of solid-phase extraction is applied to extract PPI from blood plasma in the process of biological sample preparation. The lower limit of quantification is 0.1 ng/mL with a linearity range from 0.1 to 1000 ng/mL. By the developed technique, the sample analysis of rat blood plasma was carried out after the introduction of PPI pharmaceutical substance in a dose of 20 mg/kg, a pharmacokinetic profile of the substance was established, and pharmacokinetic parameters were calculated in order to judge the degrees and rates of absorption and excretion of the new antiulcer drug in the blood of laboratory rats. [ABSTRACT FROM AUTHOR]