Premium
A new validated HPLC method for the determination of levodopa: Application to study the impact of ketogenic diet on the pharmacokinetics of levodopa in Parkinson's participants
Author(s) -
Elbarbry Fawzy,
Nguyen Van,
Mirka Alar,
Zwickey Heather,
Rosenbaum Richard
Publication year - 2019
Publication title -
biomedical chromatography
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.4
H-Index - 65
eISSN - 1099-0801
pISSN - 0269-3879
DOI - 10.1002/bmc.4382
Subject(s) - chemistry , levodopa , pharmacokinetics , chromatography , protein precipitation , high performance liquid chromatography , relative standard deviation , methanol , pharmacology , parkinson's disease , detection limit , medicine , disease , organic chemistry
A simple, accurate, and reproducible HPLC‐UV method has been developed and validated for the quantification of levodopa ( l ‐Dopa) in human plasma. The method involves a simple protein precipitation procedure to extract both l ‐Dopa and methyldopa, the internal standard. The chromatographic analysis was achieved on a Shimadzu LC 20A HPLC system equipped with a Zorbax Eclipse XDB C 18 column and an isocratic mobile phase consisting of 20 m m KH 2 PO 4 (pH 2.5) and methanol (95:5, v/v) run at a flow rate of 1 mL/min. The UV detection wavelength was set at 230 nm. The method exhibited good linearity ( R 2 > 0.999) over the assayed concentration range (0.1–10 μg/mL) and demonstrated good intra‐ and inter‐day precision and accuracy (relative standard deviations and the deviation from predicted values were <15%). This method was also successfully applied for studying the potential effect of ketogenic diet on the pharmacokinetics of l ‐Dopa in Parkinson's participants. Our data analysis indicates that ketogenic diet does not significantly affect the pharmacokinetics of l ‐Dopa.