Construction of aptamer electrochemical sensor based on SWCNHs@HPtCs complexes for perforin detection
MENG Fanfei;LIU Fei;LIU Chang;JIANG Dongneng;PU Xiaoyun;Department of Clinical Laboratory,Xinqiao Hospital,Third Military Medical University;
Objective To construct an aptamer electrochemical sensor based on single-walled carbon nanohorns(SWCNHs) and hollow Pt chains(HPtCs) complex(SWCNHs@ HPtCs). Methods A solution containing single-wall carbon nanotubes(SWCNTs) was added on a clean glassy carbon electrode(GCE) to form a film on the surface of the electrode. A film of nano-gold was electrodeposited on the surface of the electrode by cyclic voltammetry(CV) to form Au NPs/SWCNTs/GCE. The SWCNHs @ HPtCs complex was prepared by immobilizing perforin aptamers on the electrode surface and labeling aminoferrocene(AFc) as a signal carrier. When the target existed,the aptamers,perforin and antibodies formed a sandwich structure,which would connect AFc labeled HPtCs@ SWCNHs complex to the electrode surface. And then detection of differential pulse voltammetry(DPV) would display the changes of AFc reduction peak current to achieve the identification of perforin and quantitative detection. Results The SWCNHs@ HPtCs complex was prepared successfully. The optimal pH value of the detection solution was 6. 5 and the optimal incubation time of the complex was 60 min. Under the optimal experimental conditions,the current was decreased by 6. 3% after 50 cycles of consecutive scanning. There was a good linear relationship between the concentration of perforin in the range of 1 to 20 nmol/L and the peak current of the DPV. The detection limit was 0. 56 nmol/L.Conclusion Our prepared electrochemical sensor has the characteristics of fast current response,high sensitivity,good stability and good selectivity,and can be applied to the detection of perforin.
【CateGory Index】： R446.6