Determination of lead(II) by adsorptive stripping voltammetry using a glassy carbon electrode modified with β-cyclodextrin and chemically reduced graphene oxide composite

A nanocomposite consisting of beta-cyclodextrin and chemically reduced graphene oxide (beta-CD-rGO) was synthesized by chemical reduction of graphene oxide in the presence of beta-CD. The morphology and structure of the nanocomposite were characterized using transmission electron microscopy, scanning electron microscopy, FTIR and Raman spectroscopy. The nanocomposite was cast onto a glassy carbon electrode to obtain a modified electrode. Due to its large surface area, fast electron transfer ability and the numerous functional groups of the composite, the modified electrode exhibits strong electrochemical response toward lead ion (Pb2+), as determined by differential pulse anodic stripping voltammetry. Under the optimal conditions, the stripping peak currents are linearly related to the concentrations of Pb2+ over the range from 1.0 to 100 nM. The limit of detection is 0.5 nM at a signal-to-noise ratio of 3. The modified electrode had been applied to the single-shot detection of Pb2+ in industrial waste water, and satisfactory results were obtained.