Analytical Quality by Design (AQBD) Assisted Development and Validation of HPTLC Method for Estimation of Rottlerin in Topical Patch Formulation

Background: Rottlerin, a natural polyphenolic ketone is a major constituent of Mallotus philippensis (Lam.) Mull. Arg. plant. Although, less explored it has diverse array of therapeutic applications. Objectives: The current work aimed to develop novel, simple, speedy, accurate, potent High Performance Thin Layer Chromatography Method (HPTLC) to separate, and quantify rottlerin from the herbal topical patch In-House formulation. Materials and Methods: This was the foremost attempt to develop and validate HPTLC method using Analytical Quality by design (AQbD) approach. Box Behnken design (BBD) coupled with response surface methodology approach was followed for the systematic optimization. The end results of toluene content, chamber conditioning time, and solvent front on R_f value of rottlerin was studied. The optimised method was validated as per ICH guidelines. Results: For HPTLC, stationary phase used was aluminium plates 60F₂₅₄ coated with silica gel as. AQbD optimised conditions were mobile phase proportion namely toluene: ethyl acetate: methanol: ammonia (5:4:2:0.2), development distance 80 mm, band width 6mm, and chamber saturation time 10 min. The method generated well resolved and compact bands at R_f of 0.41±0.05. The developed method exhibited high accuracy, precision, robustness, and recovery. The quantity of Rottlerin in developed herbal patch was found to be 134.8 ng/band. Conclusion: In a nutshell, the present study undeniably vouches for a QbD based method development approach for Rottlerin and can be extrapolated to estimate it in other herbal extracts, or marketed formulations