Electrochemical selectivity enhancement by using monosuccinyl β-cyclodextrin as a dopant for multi-wall carbon nanotube-modified glassy carbon electrode in simultaneous determination of quercetin and rutin

Monosuccinyl β-cyclodextrin (succinyl-β-CD) was synthesized and the selectivity to quercetin and rutin of the succinyl-β-CD-modified, multi-wall carbon nanotube (MWNT)-coated, glassy carbon electrode [(succinyl-β-CD + MWNT)/GCE] was investigated. 1H NMR and MALDI-MS data confirmed molecular structure of the synthesized succinyl-β-CD. As a dopant in carboxylated MWNT-modified electrode, succinyl-β-CD clearly separated the peak potential (Ep) of quercetin from that of rutin. The measured peak potential separation (ΔEp) was 110 mV. More favorable complexation between succinyl-β-CD and quercetin may enhance relative selectivity to quercetin of the (succinyl-β-CD + MWNT)/GCE in quercetin-rutin mixture as compared to the β-CD-modified GCE.