Reversed-phase high-performance liquid chromatographic investigation of levodopa preparations I: Amino acid impurities.
A reversed-phage high-performance liquid chromatographic procedure with UV detection at 280 mm is presented for the determination of 6-hydroxydopa, tyrosine, 3-O-methyldopa, and other trace amino acid impurities in levodopa preparations. The method is fast and sufficiently sensitive to determine trace impurities at 0.1% of the levodopa concentration with a relative standard deviation of 4-6%. The trace impurities can be estimated at less than or equal to 0.01%.
D000596:Amino Acids / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D004340:Drug Contamination; D007980:Levodopa / Q000032:analysis*
D000596:Amino Acids; D007980:Levodopa