An ultra-sensitive and selective electrochemical sensor based on GOCS composite and ion imprinted polymer for the rapid detection of Cd2+in food samples

An ultra-sensitive and selective electrochemical sensor was proposed through the combination of carbon disulfide-functionalized graphene oxide (GOCS) composite with high conductivity and cadmium ion-imprinted polymer (IIP). Using pyrrole as the functional monomer and Cd2+ as the template ion, the IIP was formed by in situ electropolymerization on GOCS composite. Under the optimized experimental conditions, the sensor exhibited a good linear relationship in the range of 0.5-50 mu g/L Cd2+ concentration, with the lowest detection limit of 0.23 mu g/L. The sensor exhibited not only good selectivity for the determination of Cd2+, but also good repeatability with current response remaining 87.6 % after four cycles. Furthermore, the sensor exhibited similar sensing performance in lettuce, orange and peach with recovery ranging from 82.6 % to 110.63 %. This work is expected to provide an electrochemical sensor with excellent selectivity, good stability and sensitivity for the detection of trace amounts of Cd2+ in real samples.

Automated summary

An ultra-sensitive and selective electrochemical sensor was developed by combining carbon disulfide-functionalized graphene oxide (GOCS) composite with cadmium ion-imprinted polymer (IIP). The sensor showed a good linear relationship in the concentration range of 0.5-50 μg/L Cd2+, with a detection limit of 0.23 μg/L. It exhibited good selectivity and repeatability, and similar sensing performance in lettuce, orange, and peach.