Optosensor Based on Moleculary Imprinted Polymer Coated Quantum Dots Composited with Polypyrrole for Ampicillin Detection

Abstract

This thesis aimed to develop a nanooptosensor of molecularly imprinted polymer coated quantum dots composited with polypyrrole (PPy-QDs-MIP) for the determination of ampicillin. The integration of good fluorescence intensity of QDs, high selectivity of MIP and high affinity of PPy exhibited high sensitivity and selective recognition and facilitated the adsorption capability for trace ampicillin analysis. Under the optimal conditions, the fluorescence intensity of the developed nanocomposite probe was effectively quenched linearly with the concentration of ampicillin over two linear ranges of 0.10 to 25.0 μg L-1 and 25.0 to 100.0 μg L-1. The limit of detection is 0.05 μg L-1. The developed method was successfully applied for the determination of ampicillin in milk and meat samples and gave satisfactory recoveries between 81.7 and 98.7% and the relative standard deviations were less than 5%. The results were in good agreement with HPLC method. The advantages of developed PPy-QDs-MIP nanooptosensor were simple to operate, rapid for detection, high sensitivity and good selectivity. This developed strategy can be applied for the detection of other compounds in various samples.