Plasma measurements of levodopa and its major metabolites including dopamine and 3-O-methyldopa have been limited by cumbersome methods and poor sensitivity within relatively narrow ranges of plasma levels. We now report a modification of an HPLC method that permits concomitant measurements of a wide range of concentrations of levodopa, dopamine (DA), carbidopa, 3-O-methyldopa (3-OMD) and 3,4-dihydroxyphenyl acetic acid (DOPAC) from one HPLC injection. The recoveries ranged from 77 to 107% with an intra-day precision around 5% (CV) and inter-day CV's about 10-20%. This validated method will simplify pharmacokinetic studies of levodopa and its metabolites for mechanistic studies or therapeutic clinical monitoring which play a crucial role in development of strategies to prolong motor benefits from individual doses and reduce involuntary movements called dykinesias.
|Number of pages||4|
|Journal||Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences|
|State||Published - May 19 2006|
- DOPAC (3,4-dihydroxyphenyl acetic acid)
- Plasma measurements