Development and Validation of HPTLC Densitometric Method for Simultaneous Estimation of Quercetin and Kaempferol in Herbal Extracts and Polyherbal Formulation

Abstract

Flavonoids are a class of phytochemicals, discovered in the 1930s, that generate pigment in plants and play various biological roles in other cellular processes. It is estimated that the average dietary intake of flavonoids in humans is several hundred mg per day. Quercetin and kaempferol, the most abundant dietary flavonoids, has been reported for its strong antioxidant capabilities, anti-obesity and anti-inflammatory activities. Therefore, a simple, reproducible, robust and precise high-performance thin layer chromatography (HPTLC) densitometric method was developed and validated for the simultaneous estimation of quercetin and kaempferol as per ICH guidelines. Quercetin and kaempferol were separated on aluminium-backed silica gel 60 F254 plates using toluene: ethyl acetate: methanol: formic acid (5:3:1:0.2, % v/v) as the mobile phase. This system was found to give compact bands of kaempferol and quercetin at Rf value 0.64 ± 0.05 and 0.69 ± 0.05, respectively. The proposed method was employed with a high degree of precision and accuracy for the simultaneous estimation of quercetin and kaempferol in methanolic extracts of petals of Rosa damascena Mill., whole plant of Origanum vulgare Linn., rhizomes of Nardostachys jatamansi DC., seeds of Trachyspermum ammi Linn. and Apium graveolens Linn., and in-house Unani formulation Safoof-e-Muhazzil containing these plants as ingredients.