Development and Validation of UPLC–PDA Method for Quality Control of Dikamali gum—A Natural Tablet Binder: Fast Simultaneous Quantitation of Six Polymethoxyflavones

Abstract

Dikamali gum (Gardenia lucida Roxb., Family—Rubiaceae) in wet and dry form is used as one of the popular tablet binders in the Indian traditional herbal formulations. Recently, its application as a binder in modern drug delivery has also been reported. However, its quality specification is yet to be established. To the best of our knowledge, no validated method is reported so far for the quality assurance of Dikamali. A new reverse-phase ultraperformance liquid chromatography–photodiode array (UPLC–PDA) method was developed for the simultaneous quantification of six polymethoxyflavones (PMFs), viz., gardenin E, gardenin D, xanthomicrol, 5-desmethynobiletin, gardenin A, and gardenin B, in Dikamali gum using a Waters X-select C18 (2.5 µm, 2.1 × 100 mm) column. The influence of acid additive in mobile phase on peak response and column temperature on the peak resolution was also investigated. ICH guideline was followed for method validation of analytical procedures for the compliance of precision, accuracy, linearity, etc. The method is about three times faster than classical HPLC analysis and completed within 15 min. The limits of detection (LOD) and limit of quantitation (LOQ) were in the range 0.02–0.06 and 0.08–0.20 µg mL− 1, respectively. Calibration curves were linear from 0.18 to 1.78 µg mL− 1 with acceptable correlation coefficients ranged 0.9993–0.9999. The percent mean recoveries of the PMFs were ranged from 96.07 to 101.69%. Successful analysis of three G. lucida samples from different locations demonstrated the method to be reproducible and convenient. The present work also provides some references for quality specification of G. lucida based on polymethoxyflavones.