Simultaneous determination of quercetin and its metabolites in rat plasma by using ultra-high performance liquid chromatography tandem mass spectrometry.

Fast, selective, and sensitive ultra-high performance liquid chromatography method with tandem mass spectrometry detection for the determination of quercetin and its metabolites with various physico-chemical properties such as molecular weight, lipophilicity, and acid-base properties has been developed. These compounds included small hydrophilic phenolic acids and more lipophilic metabolites with preserved flavonoid structure in small amount of rat plasma. The developed method enables selective separation of phenolic acids and a pair of isomers tamarixetin and isorhamnetin with satisfactory peak shapes and a high sensitivity using mass spectrometry detection.

Current antiviral drugs and their analysis in biological materials - Part II: Antivirals against hepatitis and HIV viruses.

This review is a Part II of the series aiming to provide comprehensive overview of currently used antiviral drugs and to show modern approaches to their analysis. While in the Part I antivirals against herpes viruses and antivirals against respiratory viruses were addressed, this part concerns antivirals against hepatitis viruses (B and C) and human immunodeficiency virus (HIV). Many novel antivirals against hepatitis C virus (HCV) and HIV have been introduced into the clinical practice over the last decade.

Current antiviral drugs and their analysis in biological materials-Part I: Antivirals against respiratory and herpes viruses.

This review article is the first in the series providing an overview of currently used antiviral drugs and presenting contemporary approaches to their analysis. Large number of available antivirals and their structural variability makes this task very challenging. Trying to cover this topic comprehensively while maintaining reasonable size of the article, the review is presented in two parts.

Development, validation and comparison of UHPSFC and UHPLC methods for the determination of agomelatine and its impurities.

Agomelatine is one of the newest antidepressants. Due to a different mechanism of action it offers a completely new approach in the treatment of depressive disorders. Two chromatographic methods for determination of agomelatine and its impurities were developed.