An electrochemical immunosensor modified with nanocomposite was constructed to detect cytokeratin 19 fragment antigen 21-1(CYFRA21-1)which was a lung cancer marker.Ordered mesoporous carbon CMK-3 was combined with carboxylated multi walled carbon nanotubes(CMWCNTs)to improve the electron transfer rate and achieve electrochemical signal amplification.Au nanoparticles(AuNPs)were combined furtherly to prepare an electrochemical immunosensor on a glassy carbon electrode.AuNPs could be uniformly compounded with CMK-3@CMWCNTs and combined with the CYFRA21-1 antibody through the Au-S bond,providing a large number of biological binding sites for the antibody and improving the sensitivity of the sensor,so as to realize the detection of CYFRA21-1 in serum through antigen-antibody specific reaction.Scanning electron microscope characterization showed that AuNPs were embedded in the surface and pores of CMK-3@CMWCNTs.The trends of cyclic voltammetry(CV)curves showed that the constructed electrochemical immunosensor was sensitive and effective.The linear range of the constructed electrochemical immunosensor for detection of CYFRA21-1 in serum was 0.5-1×104 ng·L-1,with detection limit(3S/N)of 0.2 ng·L-1.The spiked recovery of CYFRA21-1 in the serum sample was in the range of 91.4%-102%,with RSDs(n=6)of the determined values less than 7.0%.
关键词
电化学免疫传感器/细胞角蛋白19片段抗原21-1(CYFRA21-1)/金纳米粒子/有序介孔碳
Key words
electrochemical immunosensor/cytokeratin 19 fragment antigen 21-1(CYFRA21-1)/Au nanoparticle/ordered mesoporous carbon
维普
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