摘要
An ultrasensitive electrochemical aptasensor is presented for prostate specific antigen(PSA) detection. DNA tetrahedronaptamer is designed, which not only facilitates the molecular self-assembly events,but also improves the recognition efficiency between PSA and aptamer sequence on the electrode interface. The DNA conformation on top of DNA tetrahedron changes accordingly, which can be further digested by Exonuclease T(Exo T), a type of single-strand specific nuclease. Electrochemical species are removed synchronously and the initial PSA level can thus be determined. A linear range from 0.5 pg mL^(-1) to50 ng mL^(-1) is achieved with the limit of detection(LOD) as low as 0.15 pg mL^(-1). Moreover, this proposed method is highly selective and is successfully applied to determine PSA in human serum samples.
An ultrasensitive electrochemical aptasensor is presented for prostate specific antigen（PSA） detection. DNA tetrahedronaptamer is designed, which not only facilitates the molecular self-assembly events,but also improves the recognition efficiency between PSA and aptamer sequence on the electrode interface. The DNA conformation on top of DNA tetrahedron changes accordingly, which can be further digested by Exonuclease T（Exo T）, a type of single-strand specific nuclease. Electrochemical species are removed synchronously and the initial PSA level can thus be determined. A linear range from 0.5 pg mL^-1 to50 ng mL^-1 is achieved with the limit of detection（LOD） as low as 0.15 pg mL^-1. Moreover, this proposed method is highly selective and is successfully applied to determine PSA in human serum samples.
基金
supported by the National Natural Science Foundation of China(81771929)
China Postdoctoral Science Foundation(2017M611911)
