Highly efficient fluorescent QDs sensor for specific detection of protein through double recognition of hybrid aptamer-molecular imprinted polymers

This work demonstrates a strategy of double recognition hybrid aptamer–molecular imprinted polymer/quantum dots (apt–MIP/QDs) fluorescent sensor for specific recognition of target protein. We selected vinyl modified Mn–doped ZnS QDs as signal source and support. Instead of relying on single source of weak interaction between protein and small molecule monomer, thiol terminated aptamers were used as specific functional monomers to obtain apt–MIP on the surface of QDs. The double recognition was based on aptamer and imprinted cavity to overcome the challenges of protein imprinting. The synergistic effect of the aptamer and MAA contributed for highly specific recognition ability of the apt–MIP/QDs sensor toward Cyt C. The imprinting factor and the selectivity factor values of the hybrid apt–MIP/QDs sensor were 3.17 and 8.33, respectively. This composite sensor showed an excellent linear correlation for Cyt C in the concentration range of 0.20–2.00 μM. The detection limit for Cyt C was 0.054 μM A sensitive, rapid and convenient recognition system for Cyt C in biological samples was developed. The recoveries were between 94.2% and 102.5% for urine and serum samples.