High-performance thin-layer chromatographic–densitometric determination of secoisolariciresinol diglucoside in flaxseed

A HPTLC–densitometric method, based on an external standard approach, was developed in order to obtain a novel procedure for routine analysis of secoisolariciresinol diglucoside (SDG) in flaxseed with a minimum of sample pre-treatment. Optimization of TLC conditions for the densitometric scanning was reached by eluting HPTLC silica gel plates in a horizontal developing chamber. Quantitation of SDG was performed in single beam reflectance mode by using a computer-controlled densitometric scanner and applying a five-point calibration in the 1.00–10.00 g/spot range. As no sample preparation was required, the proposed HPTLC–densitometric procedure demonstrated to be reliable, yet using an external standard approach. The proposed method is precise, reproducible and accurate and can be employed profitably in place of HPLC for the determination of SDG in complex matrices.