High performance liquid chromatography analysis of D-penicillamine by derivatization with N-(1-pyrenyl)maleimide (NPM).

D-Penicillamine (2-amino-3-mercapto-3-methylbutanoic acid), a well-known heavy metal chelator, is the drug of choice in the treatment of Wilson's disease and is also effective for the treatment of several disorders including rheumatoid arthritis, primary biliary cirrhosis, scleroderma, fibrotic lung diseases and progressive systemic sclerosis. The method proposed incorporates a technique, previously developed in our laboratory, that utilizes the derivatizing agent N-(1-pyrenyl)maleimide (NPM) and reversed-phase high-performance liquid chromatography (HPLC). The coefficients of variation for within-run precision and between-run precision for 500 nM standard D-penicillamine (D-pen) were 2.27% and 2.23%, respectively. Female Sprague-Dawley rats were given 1 g/kg D-pen i.p. and the amounts of D-pen in liver, kidney, brain and plasma were subsequently analyzed. This assay is rapid, sensitive and reproducible for determining D-pen in biological samples.