Poly-lysine/cyclodextrin polymer-MWCNTs as a selective sensing platform for hydroquinone and catechol simultaneous determination

Abstract

Electropolymerization of L-lysine incorporating multiwall carbon nanotubes (MWCNTs) dispersed in β-cyclodextrin prepolymer (CDP) solution was constructed a very efficient sensor. Scanning electron microscopy was employed to characterize the surface morphology of the modified electrode. The proposed sensor excellently enhanced the selectivity in the simultaneous determination of HQ and CC by differential pulse voltammetry and cyclic voltammetry. Comparing with bare GCE, MWCNTs/GCE, CDP-MWCNTs/GCE, the introduction of L-lysine polymer film effectively declined the shoulder peak of buffer soultion which seriously interfered the dection of hydroquinone (HQ) and catechol (CC) isomers. The PLL/CDP-MWCNTs/GCE displayed good discrimination ability and high sensitivity toward HQ and CC, peak-to-peak separation about 105 mV were obtained. The linear response range for hydroquinone and catechol were 0.1 μM - 100 μM. The detection limits of HQ and CC were 0.044 μM, 0.058 μM, respectively.