Application of graphene for preconcentration and highly sensitive stripping voltammetric analysis of organophosphate pesticide.

Electrochemical reduced β-cyclodextrin dispersed graphene (β-CD-graphene) was developed as a sorbent for the preconcentration and electrochemical sensing of methyl parathion (MP), a representative nitroaromatic organophosphate pesticide with good redox activity. Benefited from the ultra-large surface area, large delocalized π-electron system and the superconductivity of β-CD-graphene, large amount of MP could be extracted on β-CD-graphene modified electrode via strong π-π interaction and exhibited fast accumulation and electron transfer rate. Combined with differential pulse voltammetric analysis, the sensor shows ultra-high sensitivity, good selectivity and fast response. The limit of detection of 0.05 ppb is more than 10 times lower than those obtained from other sorbent based sensors. The method may open up a new possibility for the widespread use of electrochemical sensors for monitoring of ultra-trace OPs.