title: A host-guest-recognition-based electrochemical aptasensor for thrombin detection.
abstract: A sensitive electrochemical aptasensor for thrombin detection is presented based on the host-guest recognition technique. In this sensing protocol, a 15 based thrombin aptamer (ab. TBA) was dually labeled with a thiol at its 3' end and a 4-((4-(dimethylamino)phenyl)azo) benzoic acid (dabcyl) at its 5' end, respectively, which was previously immobilized on one Au electrode surface by AuS bond and used as the thrombin probe during the protein sensing procedure. One special electrochemical marker was prepared by modifying CdS nanoparticle with β-cyclodextrins (ab. CdS-CDs), which employed as electrochemical signal provider and would conjunct with the thrombin probe modified electrode through the host-guest recognition of CDs to dabcyl. In the absence of thrombin, the probe adopted linear structure to conjunct with CdS-CDs. In present of thrombin, the TBA bond with thrombin and transformed into its special G-quarter structure, which forced CdS-CDs into the solution. Therefore, the target-TBA binding event can be sensitively transduced via detecting the electrochemical oxidation current signal of Cd of CdS nanoparticles in the solution. Using this method, as low as 4.6 pM thrombin had been detected.
authors.affiliation: Department of Pharmacy, Jiangxi University of Traditional Chinese Medicine, Jiangxi, China; Department of Chemistry, East China Normal University, 3663, Zhongshan Road (N), Shanghai, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Fan
authors.affiliation: Department of Chemistry, East China Normal University, 3663, Zhongshan Road (N), Shanghai, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Chemistry, East China Normal University, 3663, Zhongshan Road (N), Shanghai, China.
authors.forename: Qingjiang
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Chemistry, East China Normal University, 3663, Zhongshan Road (N), Shanghai, China. Electronic address: pghe@chem.ecnu.edu.cn.
authors.forename: Pingang
authors.initials: P
authors.lastname: He
authors.affiliation: Department of Chemistry, East China Normal University, 3663, Zhongshan Road (N), Shanghai, China.
authors.forename: Yuzhi
authors.initials: Y
authors.lastname: Fang
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry; D015374:Biosensing Techniques / Q000379:methods*; D019187:Cadmium Compounds; D055664:Electrochemical Techniques; D053768:Metal Nanoparticles / Q000737:chemistry / Q000648:ultrastructure; D046529:Microscopy, Electron, Transmission; D019906:Nuclear Magnetic Resonance, Biomolecular; D013440:Sulfides; D013917:Thrombin / Q000032:analysis*; D047392:beta-Cyclodextrins
chemical_list: D052157:Aptamers, Nucleotide; D019187:Cadmium Compounds; D013440:Sulfides; D047392:beta-Cyclodextrins; C034939:cadmium sulfide; C081676:thrombin aptamer; D013917:Thrombin