Development and Validation of an HPTLC - Densitometric Method for Determination of Levodopa in seeds of Mucuna pruriens and its capsule dosage form

Abstract

A simple, sensitive, selective HPTLC - densitometric method was developed and validated for the
determination of Levodopa in seeds of Mucuna pruriens and its herbal dosage form. Analysis of
Levodopa was carried out on TLC plates pre-coated with silica gel 60F254 as stationary phase. Linear
ascending development of the plate was done in a pre-saturated twin trough glass chamber. The
mobile phase consisted of n-butanol – glacial acetic acid – water (5:1:4, v/v/v) at room temperature
(25 ± 2º C). Camag TLC scanner III was used for spectrodensitometric scanning and analysis was
done in absorption mode at 280nm. The system gave compact spot for Levodopa (Rf value of 0.39 ±
0.04). The polynomial regression analysis data for the calibration plots showed correlation coefficient
r = 0.999 in concentration range 100 – 1000 ng/ spot with respect to peak area. According to
International Conference on Harmonization (ICH) guidelines, the method was validated for precision,
recovery, robustness and ruggedness. The limits of detection and quantification were determined. The
statistical data analysis showed that the method is reproducible and selective for estimation of
Levodopa.