Quantitative TLC analysis of sterol (24β-ethylcholesta-5,22E,25-triene-3β-ol) in agnimantha (Clerodendrum phlomidis linn)

A quantitative method using silica gel 60F(254) high performance thin layer chromatography plates, automated bandwise sample application, and automated visible mode densitometric method has been developed for the determination of 24 beta-ethylcholesta-5,22E,25-triene-3 beta-ol (ECTO) in the aerial part of Clerodendrum phlomidis. ECTO was used as a chemical marker for the standardization of C. phlomidis plant extracts. The separation was performed on silica gel 60F(254) TLC plates using chloroform-methanol (98.5: 1.5, v/v) as mobile phase. The quantitation of ECTO was carried out using the densitometric reflection/absorption mode at 650 nm after post chromatographic derivatization with anisaldehyde reagent. A precise and accurate quantification can be performed in the linear working concentration range of 150-400 ng band(-1) with good correlation (r(2)= 0.996). The method was validated for peak purities, precision, robustness, limit of detection (LOD) and quantitation (LOQ), etc. as per ICH guidelines.