A Thin Layer Chromatography Densitometric Method for Assay of Folic Acid in Tablets

Abstract

A High Performance Thin Layer Chromatography (HPTLC) method for analysis of
folic acid was developed and validated according to ICH and USP guidelines. The
developed method was used for simultaneous qualitative and quantitative analysis
of folic acid in tablets. The method was developed using an environmentally
friendly mobile phase containing ethyl acetate:methanol:ammonia solution
(15:15:0.5 v/v/v) on pre-coated HPTLC silica gel 60 F254 glass plates at a detection
wavelength of 280 nm using reflectance absorbance and saturation time of 25 min.
Densitometric analysis showed two folic acid products being retained at Rf of 0.27
and 0.67 and the area was taken as the sum of the two. The method was specific and
no interferences were observed between folic acid peaks and that of the excipients.
The calibration curve of folic acid was constructed using both linear and
polynomial regression function in the range of 317.19–761.25 ng/spot both with
regression coefficient, r2 of 0.998. The accuracy at nominal concentration of folic
acid was found to be 101.05%, % rsd, repeatability and intermediate precision
were found to be 1.79% and 1.93 respectively. The developed method is thus simple,
accurate, and cost effective with good precision and repeatability for the assay of
folic acid in tablets which will be particularly useful in resource constrained
countries.

Key words: High performance thin layer chromatography, densitometry, validation, folic acid