title: Sensitive electrochemical aptasensor for thrombin detection based on graphene served as platform and graphene oxide as enhancer.
abstract: A sensitive electrochemical aptasensor was developed with conductive graphene served as platform and inert graphene oxide (GO) as enhancer. An electrodeposited nano-Au layer was firstly formed on conductive graphene modified glass carbon electrode surface for further immobilizing of electrochemical redox probe hexacyanoferrates nanoparticles (NiHCFNPs). Subsequently, another nano-Au layer was formed for immobilizing of thrombin aptamer (TBA). In the presence of thrombin, the TBA on the electrode surface could bind with thrombin, which made a barrier for electrons and inhibited the electro-transfer, resulting in the decreased electrochemical signals of NiHCFNPs. Owing to the non-conductivity property of graphene oxide, further decreased electrochemical signals of NiHCFNPs could be obtained via the sandwich reaction with GO-labeled TBA. According to the signal changes before the thrombin recognition and after sandwich reaction, trace detection of thrombin could be achieved. As a result, the proposed approach showed a high sensitivity and a wider linearity to thrombin in the range from 0.005 nM to 50 nM with a detection limit of 1 pM.
authors.affiliation: College of Chemistry and Chemical Engineering, Yibin University, Sichuan, 644000, China.
authors.forename: Chun
authors.initials: C
authors.lastname: He
authors.forename: Zenghong
authors.initials: Z
authors.lastname: Xu
authors.forename: Tao
authors.initials: T
authors.lastname: Sun
authors.forename: Li
authors.initials: L
authors.lastname: Wang
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry*; D002138:Calibration; D002244:Carbon / Q000737:chemistry; D055664:Electrochemical Techniques / Q000379:methods*; D004566:Electrodes; D005898:Glass / Q000737:chemistry; D006046:Gold / Q000737:chemistry; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D053758:Nanoparticles / Q000737:chemistry; D010087:Oxides / Q000737:chemistry*; D015203:Reproducibility of Results; D013917:Thrombin / Q000032:analysis*
chemical_list: D052157:Aptamers, Nucleotide; D010087:Oxides; C081676:thrombin aptamer; D002244:Carbon; D006046:Gold; D006108:Graphite; D013917:Thrombin