A cyclodextrin-deep eutectic solvent-based dispersive liquid-liquid microextraction method for quantitative...

In this study, a cyclodextrin-dispersive liquid-liquid microextraction-HPLC-based method was developed to quantitatively study four components of Codonopsis Radix (CR): carboxymethyl-β-cyclodextrin (CM-β-CD) was incorporated into the DES, then added to the sample solution, and the mixture was vortexed and centrifuged, the upper hydrophobic phase was then collected for HPLC analysis. The primary elements influencing the extraction efficiency were optimized to choose the circumstances for this experiment, including the type and consumption of cyclodextrin, the NaCl concentration, the pH level of the sample phase and the extraction time. The EFs for four target components extracted by cyclodextrin-DES were between 8.4 and 71.2, which were all higher than those extracted only by DES. In their respective linearity ranges, the four analytes exhibited good linearity (R² ≥ 0.99), with detection limits of 1.2 × 10^-2 μg/mL, 5.3 × 10^-3 μg/mL, 3 × 10^-4 μg/mL, and 1.1 × 10^-4 μg/mL. The precision and accuracy of the method ranged from 0.8 % to 10.0 % and 90.0 % to 105.2 %. Finally, this method was applied to the quantification of fresh-cut CR and traditional-processed CR. The results showed that the content of tangshenoside I and lobetyolinin of fresh-cut CR was significantly higher than in traditionally processed CR, but there were no significant differences between fresh-cut CR and traditionally processed CR for lobetyolin and lobetyol. The use of CM-β-CD in combination with DES provides rapid, simple, and reliable quantification of the target analytes. By this method, differences between the two processing methods were compared at the level of small-molecule content, providing evidence for the feasibility of the fresh-cutting processing method and demonstrating a theoretical basis for the quality evaluation method of the fresh-cut process.