Spectrophotometric Determination of Silymarin

Abstract

Two simple spectrophotometric methods (A and B) have been
developed for the determination of silymarin in pure form and in
its pharmaceutical formulations. Method A is based on the formation
of blood red coloured complex with ferric chloride and 1,10-
phenanthroline having absorption maximum at 510 nm. In method
B, silymarin forms blue coloured complex with Folin-cioCalteu
(FC) reagent in the presence of sodium hydroxide exhibiting maximum
absorption at 740 nm. The chromogens obey Beer's law in
tlfe concentration ranges of 2.5 to 25  μg/mL and 2.5 to 20  μg/mL
for methods A and B respectively.