ABSTRACT:
The present study aims to develop analytical method of methanolic extract of Thuja occidentalis Linn. Estimation of quercetin by TLC densitometric method can be used as one of the appropriate analytical method. The separation was performed on TLC aluminium plates precoated with silica gel 60 F254. Good separation was achieved in mobile phase using Chloroform: Ethyl acetate: Methanol: Glacial acetic acid (5:2:1.5:0.02% v/v). Determination and quantitation were performed by densitometric scanning at 420 nm in reflection/absorbance mode. This method gave compact spots at Rf 0.5 corresponding to quercetin. The method was validated using parameters such as linearity, accuracy, precision, limit of detection, limit of quantification and recovery as per ICH guidelines. The linear equation in the range of 10-60 µg/ml with y=4.139x + 623.5, and r² = 0.9981. The accuracy was found to be 98.13-99.42% recovery and interday and intraday precision was found to be 0.20-0.25 % RSD and 0.15-0.38% RSD. The LOD and LOQ value was 23.05 and 69.87ng/ml. The proposed method can be used for the reliable quantification of active marker compound in methanolic extract of Thuja occidentalis L.