Molecularly Imprinted Dispersive-Based Extraction Method for Melamine in Milk (MIDE HPLC DAD)

Abstract

An easy and selective molecularly imprinted dispersive extraction method (MIDE) coupled with HPLC-DAD was developed for melamineŽs analysis in commercial milk samples. The molecularly imprinted polymer (MIP) was synthetized by suspension polymerisation with melamine as template, while methacrylic acid, ethylene glycol dimethacrylate and chloroform were used as monomer, cross-linker and porogenic solvent, respectively. The analytical methodology was validated presenting a limit of detection of 0.6 mg/kg. The recovery percentage in spiked milk samples ranged from 92.9% to 102.0% with an intermediate precision of 5.0%. The analysis of real samples with MIDE revealed melamineŽs presence in 20% of the cases with a maximum concentration of 9.3 ± 0.3 mg/kg, which exceeds the maximum recommended level of 2.5 mg/kg.