Effervescent salt and crown ether-assisted matrix solid-phase dispersion extraction of coumarins from Cortex fraxini

A simple, rapid and environmentally friendly method named effervescence-assisted matrix solid-phase dispersion (EA-MSPD) was investigated for the extraction of four coumarins (esculin, esculetin, fraxin and fraxetin) from Crotex fraxini (C. fraxini). In this study, an effervescent tablet containing carbon dioxide sources (100 mg sodium bicarbonate and 200 mg sodium dihydrogenphosphate) and an adsorbent (25 mg benzo-15-crown-5) was prepared. The effervescent tablet was dissolved into an aqueous solution, and as a consequence of the effervescence reaction, carbon dioxide was generated, thus making the sample better a dispersion of the extraction solvent (100 mM sodium dodecyl sulfate). The variables that influenced the extraction efficiency included effervescent salts, extraction solvents and crown ether. These values were represented using ultra- high-performance liquid chromatography (UHPLC). Good linearity was exhibited by coefficients of determination all equal to 1, limits of detection ranging from 1.62 to 3.83 ng.mL(-1) and limits of quantification ranging from 5.39 to 12.76 ng.mL(-1). The recoveries ranged from 91.37 to 100.29% with relative standard deviations of 0.57-4.58% under optimized conditions. In this work, the proposed EA-MSPD method was successfully applied to extract and identify four coumarins in C. fraxini. Compared with previously reported methods, the method examined herein was faster, greener and more sensitive.