title: Horseradish peroxidase and aptamer dual-functionalized nanoprobe for the amplification detection of alpha-methylacyl-CoA racemase.
abstract: Alpha-methylacyl-CoA racemase (AMACR) is over-expressed in many cancer types and can serve as a novel diagnostic biomarker. Development of convenient and sensitive detection methods of AMACR is of particular importance for cancer diagnosis. Aptamers are a type of recognition elements, which possess many advantages over antibody, making them suitable for applications in biosensing and biotechnology. In this work, we use the efficient surface modification of gold nanoparticles (AuNPs) to prepare the horseradish peroxidase (HRP) and aptamer dual-functionalized nanoprobe. The immobilization of HRP and thiol-terminated aptamer on the surface of AuNPs can be achieved through electrostatic interaction and the formation of Au-S bond, respectively. This nanoprobe, which is used as discriminating and catalytic probe, can be combined with enzyme immunoassay method to increase the detection sensitivity of AMACR. The detection limit can reach as low as 4.6 pg mL(-1) due to the dual signal amplification from enzymatic cycling and the high loading of enzymes on AuNPs. This sensitivity is about three orders of magnitude higher than that of AMACR aptamer based fluorescence method, which is also comparable to or one order of magnitude higher than that of ELISA. Furthermore, this method is more simple and effective, which not only avoids the conjugation between recognition element and the catalytic enzyme, but also achieves greater signal amplification. This assay could be used as a sensitive and selective platform for the detection of target protein.
authors.affiliation: The United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province, Mengchao Hepatobiliary Hospital of Fujian Medical University, Fuzhou 350025, PR China; Liver Disease Center, The First Affiliated Hospital of Fujian Medical University, Fuzhou 350005, PR China.
authors.forename: Yongyi
authors.initials: Y
authors.lastname: Zeng
authors.affiliation: The United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province, Mengchao Hepatobiliary Hospital of Fujian Medical University, Fuzhou 350025, PR China; The Liver Center of Fujian Province, Fujian Medical University, Fuzhou 350025, PR China.
authors.forename: Aixian
authors.initials: A
authors.lastname: Zheng
authors.affiliation: The United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province, Mengchao Hepatobiliary Hospital of Fujian Medical University, Fuzhou 350025, PR China; The Liver Center of Fujian Province, Fujian Medical University, Fuzhou 350025, PR China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wu
authors.affiliation: The United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province, Mengchao Hepatobiliary Hospital of Fujian Medical University, Fuzhou 350025, PR China; The Liver Center of Fujian Province, Fujian Medical University, Fuzhou 350025, PR China.
authors.forename: Zhixiong
authors.initials: Z
authors.lastname: Cai
authors.affiliation: The United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province, Mengchao Hepatobiliary Hospital of Fujian Medical University, Fuzhou 350025, PR China; Department of Pathology, School of Basic Medical Science, Fujian Medical University, Fuzhou 350004, PR China. Electronic address: aimin@fjmu.edu.cn.
authors.forename: Aimin
authors.initials: A
authors.lastname: Huang
authors.affiliation: The United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province, Mengchao Hepatobiliary Hospital of Fujian Medical University, Fuzhou 350025, PR China; The Liver Center of Fujian Province, Fujian Medical University, Fuzhou 350025, PR China. Electronic address: xiaoloong.liu@gmail.com.
authors.forename: Xiaolong
authors.initials: X
authors.lastname: Liu
keywords: Alpha-methylacyl-CoA racemase; Amplification detection; Aptamer; Dual-functionalized nanoprobe; Horseradish peroxidase