Simultaneous determination of flavonoids and anthraquinones in honey by using SPE-CE-LIF

Based on advantages of capillary electrophoresis (CE), a new solid-phase extraction (SPE) coupled with CE has been developed for preconcentration, enrichment and determination of anthraquinones and flavonoids (rutin, emodin, quercetin, 1,8-dihydroxyanthraquinone) in honey. The environmental-friendly chitin activated after an easy processing is selected as the adsorbent to enrich analytes. Then, chitin was filled into the filter as the solid phase. To improve the extraction effect, some key parameters of extraction were optimized. Under the optional extraction conditions, the chitin showed excellent adsorption capacity and selectivity over rutin, emodin, quercetin, and 1,8-dihydroxyanthraquinone, with enrichment factors reaching 5 folds. The CE coupled with fluorescence detection was used for the detection. Results prove the method is simple, fast, and highly sensitive, with the limit of detection (LOD) is 3.00-200.0 ng/mL; the recovery is 90.0-107.0%, and relative standard deviation of (RSD) is 1.8-8.3%.