title: 3,4,9,10-perylenetetracarboxylic acid/hemin nanocomposites act as redox probes and electrocatalysts for constructing a pseudobienzyme-channeling amplified electrochemical aptasensor.
abstract: A simple wet-chemical strategy for the synthesis of 3,4,9,10-perylenetetracarboxylic acid (PTCA)/hemin nanocomposites through π-π interactions is demonstrated. Significantly, the hemin successfully conciliates PTCA redox activity with a pair of well-defined redox peaks and intrinsic peroxidase-like activity, which provides potential application of the PTCA self-derived redox activity as redox probes. Additionally, PTCA/hemin nanocomposites exhibit a good membrane-forming property, which not only avoids the conventional fussy process for redox probe immobilization, but also reduces the participation of the membrane materials that act as a barrier of electron transfer. On the basis of these unique properties, a pseudobienzyme-channeling amplified electrochemical aptasensor is developed that is coupled with glucose oxidase (GOx) for thrombin detection by using PTCA/hemin nanocomposites as redox probes and electrocatalysts. With the addition of glucose to the electrolytic cell, the GOx on the aptasensor surface bioelectrocatalyzed the reduction of glucose to produce H(2)O(2), which in turn was electrocatalyzed by the PTCA/hemin nanocomposites. Cascade schemes, in which an enzyme is catalytically linked to another enzyme, can produce signal amplification and therefore increase the biosensor sensitivity. As a result, a linear relationship for thrombin from 0.005 to 20 nM and a detection limit of 0.001 nM were obtained.
authors.affiliation: Key Laboratory on Luminescence and Real-Time Analysis, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing, PR China.
authors.forename: Yali
authors.initials: Y
authors.lastname: Yuan
authors.forename: Ruo
authors.initials: R
authors.lastname: Yuan
authors.forename: Yaqin
authors.initials: Y
authors.lastname: Chai
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhuo
authors.forename: Xianxue
authors.initials: X
authors.lastname: Gan
authors.forename: Lijuan
authors.initials: L
authors.lastname: Bai
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry*; D015374:Biosensing Techniques; D002384:Catalysis; D055664:Electrochemical Techniques; D005949:Glucose Oxidase / Q000737:chemistry / Q000378:metabolism; D006427:Hemin / Q000737:chemistry*; D053761:Nanocomposites / Q000737:chemistry*; D010084:Oxidation-Reduction; D010569:Perylene / Q000031:analogs & derivatives* / Q000737:chemistry
chemical_list: C560550:3,4,9,10-perylene tetracarboxylic acid; D052157:Aptamers, Nucleotide; C081676:thrombin aptamer; D010569:Perylene; D006427:Hemin; D005949:Glucose Oxidase