title: Label-free aptamer biosensor for thrombin detection based on functionalized graphene nanocomposites.
abstract: A label-free and amplified electrochemical impedimetric aptasensor based on functionalized graphene nanocomposites (rGO-AuNPs) was developed for the detection of thrombin, which played a vital role in thrombosis and hemostasis. The thiolated aptamer and dithiothreitol (TBA15-DTT) were firstly immobilized on the gold electrode to capture the thrombin molecules, and then aptamer functionalized graphene nanocomposites (rGO-TBA29) were used to fabricate a sandwich sensing platform for amplifying the impedimetric signals. As numerous negative charges of TBA29 on the electrode repelled to the [Fe(CN)6](4-/3-) anions, resulting in an obvious amplified charge-transfer resistance (Rct) signal. The Rct increase was linearly proportional to the thrombin concentration from 0.3 to 50nM and a detection limit of 0.01nM thrombin was achieved. In addition, graphene could also be labeled with other probes via electrostatic or π-π stacking interactions to produce signals, therefore different detection methods expanding wide application could be used in this model.
authors.affiliation: College of Chemistry, Jilin University, Changchun 130012, PR China; State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, PR China.
authors.forename: Qingqing
authors.initials: Q
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, PR China.
authors.forename: Zhixue
authors.initials: Z
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, PR China.
authors.forename: Yanling
authors.initials: Y
authors.lastname: Zhai
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, PR China.
authors.forename: Lingling
authors.initials: L
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, PR China.
authors.forename: Wei
authors.initials: W
authors.lastname: Hong
authors.affiliation: College of Chemistry, Jilin University, Changchun 130012, PR China. Electronic address: zzq@jlu.edu.cn.
authors.forename: Zhiquan
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, PR China. Electronic address: dongsj@ciac.ac.cn.
authors.forename: Shaojun
authors.initials: S
authors.lastname: Dong
mesh_terms: D000818:Animals; D052157:Aptamers, Nucleotide / Q000737:chemistry*; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods*; D002417:Cattle; D058266:Dielectric Spectroscopy / Q000295:instrumentation / Q000379:methods; D004566:Electrodes; D006108:Graphite / Q000737:chemistry; D057230:Limit of Detection; D053761:Nanocomposites / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry; D044967:Serum / Q000737:chemistry; D013917:Thrombin / Q000032:analysis*
chemical_list: D052157:Aptamers, Nucleotide; D006108:Graphite; D013917:Thrombin
keywords: Aptasensor; Graphene; Impedance spectroscopy; Nanocomposite; Thrombin