Optical Determination of Cholesterol in Milk with Molecularly Imprinted Polymer-Coated Quantum Dots

Fluorescent molecularly imprinted polymer-coated CdSe/ZnS quantum dots were prepared in an efficient one-step synthesis. Their application as fluorescent nanoparticles for the direct quantification of cholesterol in milk was characterized. The quantum dots were used as cores to produce fluorescence. The molecularly imprinted polymer shells provided specific binding sites for cholesterol. The system exhibited good linearity for cholesterol from 0.5 to 150 mu gmL(-1), a low detection limit of 0.15 mu gmL(-1), and acceptable reproducibility with a relative standard deviation of 4.2% for six replicates. The molecularly imprinted polymer-coated quantum dots were used to determine cholesterol in fortified milk. Recoveries were from 87.0 to 105.2% and a possible mechanism is proposed. The fluorescent molecularly imprinted polymer-coated quantum dots exhibited excellent selectivity and provide a simple, rapid, selective, and effective analytical approach.