The detection method for small molecules coupled with a molecularly imprinted polymer/quantum dot chip using a home-built optical system

A method to detect small molecules with a molecularly imprinted polymer/quantum dot (MIP-QD) chip using a home-built optical fluidic system was first proposed in this study. Ractopamine (RAC) was used as the model molecule to demonstrate its feasibility. The sensing of the target molecule is based on the quenching amount of the quantum dots. The method is facile, cost-saving, easy for miniaturization and avoids the cumbersome steps that are needed to get the fluorescent quenching curve using a spectrofluorometer. Most importantly, more details and accurate response time can be obtained by use of this method. The experimental results show that the prepared chips with low cost are highly selective and the home-built detection system allows the fast binding kinetics. The recorded quenching process was used to study the kinetic uptake of RAC onto the MIP-QD chip and the specificity towards RAC. The system can further be utilized to study the effect of the solvent, pH and temperature on the selectivity of the prepared MIP. The methodology could be extended to other similar studies with different molecules.