Synthesis of a Novel Composite Imprinted Material Based on Multiwalled Carbon Nanotubes as a Selective Melamine Absorbent

A novel composite imprinted material, on the basis of a multiwalled carbon nanotube (CNT)-incorporated layer using melamine as a template, methacrylic acid as a functional monomer, and ethylene glycol dimethacrylate as a cross-linker, was synthesized by a surface imprinting technique. The imprinted/CNT sorbent was characterized by a scanning electron microscope (SEM). Adsorption dynamics and a Scatchard adsorption model were employed to evaluate the adsorption process. The results showed that the imprinted/CNT sorbent displayed a rapid dynamic adsorption and a high adsorption capacity of 79.9 mu mol g(-1) toward melamine. Applied as a sorbent, the imprinted/CNT sorbent was used for the determination of melamine in a real sample by online solid-phase extraction high-performance liquid chromatography (SPE-HPLC). An enrichment ratio of 563-fold, detection limit (S/N = 3) of 0.3 mu g L-1; and quantification limit of 4.5 mu g L-1 were achieved.