Determination of underivatized glucosamine in human plasma by high-performance liquid chromatography with electrochemical detection: application to pharmacokinetic study.

A simple, rapid and sensitive high-performance liquid chromatography method with electrochemical detection was developed for the determination of glucosamine in human plasma. Plasma samples were analyzed after a simple two-step procedure of protein precipitation with subsequent dilution. The chromatographic separation was performed on a Carbopack column (3 mm x 150 mm) with a mobile phase consisting of water and 200 mM sodium hydroxide. Detection was performed electrochemically in a pulsed voltammetry mode. The limit of detection was 2.0 ng/ml, inter- and intra-day precision were less than 10%. The method was successfully applied to the investigation of the pharmacokinetics of glucosamine in healthy man volunteers.