An “on-off” Electrochemiluminescence Biosensor Based on Molecularly Imprinted Polymer and Recycling Amplifications for Determination of Dopamine

A novel of eco-friendly molecularly imprinted electrochemical luminescence biosensor was designed, based on nanomaterials, CdSeTe/ZnS core-shell QDs and molecularly imprinted polymer composites modified glass carbon electrode. Combining the superior selectivity of molecularly imprinted polymer and the high sensitivity of electrochemical luminescence would achieve the trace determination of dopamine. And the cavities in molecularly imprinted polymer after eluting were applied as the substrate to capture target molecular dopamine. The electron transform channel for the redox reaction of CdSeTe/ZnS QDs and co-reaction K2S2O8 was blocked with the increase of dopamine concentration, resulting in the cathodic ECL intensity decreased correspondingly. Therefore, the dopamine was detected in the concentration range from 1 × 10−14 mol/L to 2.5 × 10−12 mol/L, with the low detection limit of 3.3 × 10−15 mol/L. The MIP-ECL biosensor showed easy preparation, low lost, lower detection limit, good selectivity and stability, and could be used for the detection of dopamine in the human serum successfully.