STABILITY-INDICATING REVERSE-PHASE HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY METHOD FOR THE SIMULTANEOUS QUANTIFICATION OF APIGENIN AND LUTEOLIN FROM ACHILLEA MILLEFOLIUM LINN

Objective: A stability-indicating reverse-phase high-performance liquid chromatographic method was developed and validated for the analysis of apigenin and luteolin. The degradation behavior of apigenin and luteolin was investigated under different stress conditions as recommended by the International Conference on Harmonization (ICH). Methods: In the present study, a reversed-phase high-performance liquid chromatography method was developed and the resolution of the plant constituents was successfully achieved using Hibar Lichrospher C8 column with ultraviolet detector at a wavelength of 269 nm. The mobile phase consisted of methanol and 0.5% trifluoroacetic acid (80:20 v/v) at a flow rate of 1.0 ml/min. Both apigenin and luteolin were subjected to various stress degradation studies such as oxidation, acid and alkaline hydrolysis, and photolytic degradation. Results: The proposed method was found to be linear (1–5 μg/ml) with the linear correlation coefficient of R2=0.99. Although the degradation products of stressed conditions were not identified, the methods were able to detect the changes due to stress condition. Conclusion: The method provides good sensitivity and excellent precision and reproducibility. Forced degradation studies on apigenin and luteolin give information about their storage and intrinsic stability conditions considering the advanced pharmaceutical aspects of formulations.