Optimization of an analytical HPLC-DAD method for detecting hydroxycinnamic acid derivatives from mixtures of Saussurea grandifolia and Taraxacum coreanum

Abstract

An analytical method was established to identify and quantify hydroxycinnamic acids, such as 1,5-dicaffeoylquinic acid (DCQA) and chicoric acid (CA), in mixtures of Saussurea grandifolia and Taraxacum coreanum (MST) by using reverse-phase high-performance liquid chromatography coupled with diode array detector (HPLC-DAD). Analyses were carried out by using an INNO C₁₈ column with a gradient elution system, and different parameters were used to validate our optimized method. Results demonstrated limits of detection and quantification of 5.46 × 10^–3 and 16.54 × 10^–3 mg/mL for DCQA and 0.37 × 10^–3 and 1.14 × 10^–3 mg/mL for CA, respectively. The calibration curves for DCQA and CA showed good linearity over the concentration ranges of 0.025–0.4 and 0.00625–0.1 mg/mL, respectively, and both exhibited r² = 1.0000. In the accuracy test, high recovery rates were obtained ranging from 101.16–104.18% for DCQA and 97.55–108.49% for CA, while the precision values were ≤ 1.00% for DCQA and ≤ 1.21% for CA. The values obtained from our analyses support the use of this analytical method for the accurate identification and quantification of DCQA and CA from MST. Our methodology could be used further to determine the content of hydroxycinnamic acid derivatives in routine analyses and large-scale extraction processes.