DEVELOPMENT AND VALIDATION OF A DENSITOMETRIC HPTLC METHOD FOR QUANTIFICATION OF OPUNTIOL IN OPUNTIA ELATIOR MILL.

Opuntiol is a biologically active flavonol present in Opuntia elatior Mill. (Cactaceae) that exhibits significant pharmacological activities such as antioxidant, anti-inflammatory, and anticancer effects. Reliable analytical methods are therefore required for the quantitative estimation in plant extracts and pharmaceutical preparations. The present study aimed to develop and validate a rapid, sensitive, and reproducible densitometric HPTLC method for the quantification of Opuntiol. Opuntiol was isolated from the fruits of Opuntia elatior using column chromatography, and its purity was confirmed by TLC and UV spectroscopy. Chromatographic separation was achieved on silica gel 60 F254 plates using an optimized mobile phase consisting of ethyl acetate: water: formic acid: glacial acetic acid: n-hexane (7:1:1.1:1.1:5 v/v). Densitometric scanning was performed at 280 nm, yielding a well-resolved band with an Rf value of 0.42 ± 0.002. The method showed excellent linearity in the range of 10–120 ng/spot with a correlation coefficient of 0.9956. The limits of detection and quantification were 10.14 ± 3.04 ng/spot and 30.74 ± 9.24 ng/spot, respectively. Precision studies demonstrated %RSD values below 2%, confirming excellent repeatability and intermediate precision. The robustness of the developed method was found within acceptable limits, with %RSD values ≤2%, indicating that the method is robust and can tolerate minute deliberate changes. The accuracy study was assessed at three different concentrations: 80, 120, and 150 ng/spot. The percentage mean recoveries were accurate, with <5% deviation and 3–8% RSD, indicating method excellence. The validated HPTLC method is simple, rapid, precise, and suitable for routine quality control and standardization of Opuntia in Opuntia species and related herbal formulations.