Melamine-imprinted polymer grafts through surface photopolymerization initiated by aryl layers from diazonium salts

In this work, diazonium-based photoinitiators were electrografted on gold electrodes to provide specific, selective and ultrasensitive molecularly imprinted polymer (MIP) grafts for the detection of melamine. This toxic molecule was used as a template, while methacrylic acid (MAA) and ethylene glycol dimethacrylate (EGDMA) were the functional and crosslinking monomers, respectively. Surface-initiated photopolymerization was conducted because it is a simple and versatile mean for making ultrathin MIP grafts (similar to 25 nm thick). Both cyclic and square wave voltammetry (SWV) were used for investigating rebinding melamine by the MIP grafts. However, the latter permitted to achieve ultrasensitive detection down to 7.7 x 10(-10) mol/L in PBS and 3.1 x 10(-10) mol/L in milk. Recovery was found to be very good, levelling off at 92%. (c) 2012 Elsevier Ltd. All rights reserved.