High-efficiency extraction of multiple flavonoids from royal jelly: Optimization of carbon nanocage–assisted dispersive microsolid -pHase extraction using response surface methodology and integrated greenness assessment

Carbon nanocages (CNCs) are used as an adsorbent material in the dispersive microsolid-phase extraction (DMSPE) of flavonoid compounds in functional food before capillary electrophoresis–diode detector analysis. This method combined single-factor and response surface methods to optimize crucial parameters influencing the extraction and preconcentration efficiency. Key parameters such as adsorbent type and amount, vortex time, elution solvent type, and sample solution pH were systematically optimized to establish optimal enrichment conditions. Analytical parameters associated with the proposed method [broad linear ranges (0.1–5 μg/mL), low limits of detection (0.002–0.006 μg/mL) and limits of quantification (0.006–0.021 μg/mL), and significant coefficient of determination values (0.999)] were validated under the optimal conditions. The developed method displayed good precision (relative standard deviation% < 4.78 %) and excellent accuracy (104.9 > %recovery >81.8). Under optimized conditions, the enrichment of six flavonoids was enhanced, with enrichment factors ranging from 12 to 149. Moreover, the greenness and blueness of the proposed method were assessed and compared with reported approaches using the analytical greenness metric, green analytical procedure index and blue applicability grade index. Results revealed excellent greenness and practicality. CNC-assisted DMSPE was successfully applied to the preconcentration and determination of multiflavonoids in royal jelly samples. This method exhibits the potential of the enrichment of phenolic compounds in other complex matrix samples.