A strategy for constructing sensitive and renewable molecularly imprinted electrochemical sensors for melamine detection

A novel strategy for preparing highly sensitive and easily renewable molecularly imprinted polymer (MIP) sensors was proposed. Using melamine (MA) as the template molecule, MIP particles were synthesized and embedded in a solid paraffin carbon paste to prepare the MIP sensor. MA was indirectly determined from the competition between the reactions of MA and horseradish peroxidase-labeled MA (MA-HRP) with the vacant cavities. The detection signals were amplified because of enzymatic reaction to the H2O2 catalytic oxidation. Sensitivity was markedly improved. Sensor renewal was achieved by a simple mechanical polishing of the sensitive film. The linear range for MA detection was 0.005–1 μmol L−1 and the detection limit was 0.7 nmol L−1. The molecularly imprinted solid paraffin carbon paste sensor was used for MA detection in milk samples.

Graphical abstractA strategy for preparing molecularly imprinted electrochemical sensors with a highly sensitive and easily renewable film is proposed. Film renewability was achieved by embedding MIP particles in a solid paraffin carbon paste, and the high sensitivity was detected using a highly sensitive enzyme amplifier.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► A strategy for preparing molecularly imprinted electrochemical sensors with a highly sensitive and easily renewable film is proposed. ► MIP particles were synthesized and embedded in a solid paraffin carbon paste to prepare the MIP sensor. ► The detection signals were amplified because of enzymatic reaction to the H2O2 catalytic oxidation. ► Sensitive film renewability was achieved by embedding MIP particles in a solid paraffin carbon paste. ► Melamine was selected as the template molecule.