Simultaneous determination of five compounds in Codonopsis Radix using a hydrophobic deep eutectic solvent based on vortex-assisted dispersive liquid-liquid microextraction coupled with HPLC

[Display omitted] •A suitable DES was reported for determination of trace and highly polar components.•The method of multi-component content determination was employed to identify indicators of quality evaluation.•An easy-to-operate and sensitive VA-DES-DLLME-HPLC method was developed and applied to the traditional Chinese Medicine.•Objectively distinguish the three specifications of Codonopsis Radix by analysis of variance. A vortex-assisted dispersive liquid-liquid microextraction was proposed based on hydrophobic deep eutectic solvent and high performance liquid chromatography for the quantitative study of five small molecular compounds (tangshenoside I, lobetyolinin, lobetyolin, lobetyol, atractylenolide III) and quality evaluation of Codonopsis Radix. In this experiment, the primary factors impacting the extraction competence process were optimized. Under optimal conditions that were DES (methyltrioctylammonium chloride: glycerol, molar ratio 1:4, 70 μL), pH = 7, vortex time of 90 s, centrifugal time of 2 min, enrichment factors of 6.0, 6.2, 18.9, 58.7, 63.2 for tangshenoside I, lobetyolinin, lobetyolin, lobetyol, atractylenolide III were obtained. The detection limits of the above five components were respectively 9, 6, 2, 0.1, 0.6 µg/L and five analytes had excellent linearities in individual linear ranges (R2 > 0.990). Good precision and recovery were 0.5%-8.8% and 92.3%-111.5%. The quantitative results revealed that the proposed approach is quick, simple, feasible, and could accurately detect the contents of five target analytes in 18 batches samples. Finally, five components could be chemical markers to objectively distinguish different specifications of Codonopsis Radix by analysis of variance, further contributing a foundation for quality evaluation and control of Codonopsis Radix.