Development and validation of a visible absorption densitometry method for quantitation of conessine in Holarrhena antidysenterica (Kurchi).

A selective, precise, and accurate high-performance thin-layer chromatographic (HPTLC) method has been proposed for the analysis of conessine in Holarrhena antidysenterica. The method involves visible densitometric evaluation of conessine resolving it by HPTLC on aluminium-based silica gel plates. For visible densitometric evaluation, peak areas were recorded at 520 nm after the resolved bands were derivatized with Dragendorff's reagent and then sprayed with a 10% solution of aqueous sodium nitrite which resulted in reddish brown color. The correlation between the concentration and area was found to be linear within the range of 10 to 60 ng/spot. The method was validated for precision (interday and intraday), repeatability, and accuracy. Mean recovery for conessine was 98.34-100.25%. The method was applied for the quantitation of conessine in Kurchi. The proposed HPTLC method was found to be precise, specific, sensitive, and accurate and can be used for routine analysis of Kurchi.