Self-assembled perylenetetracarboxylic acid-reduced graphene oxide film for high-sensitive impedimetric determination of thrombin

• Published in: Surface & coatings technology Vol. 402; p. 126491
• Main Authors: Wu, Hao, Xi, Ke, Xiao, Shu, Ngai, Sieglind, Zhou, Chilou, He, Mohan, Shi, Kejun, Yu, Yu, Yang, Yuhang, Chen, Guohua, Ding, Kejian
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 25.11.2020; Elsevier BV
• Subjects: Aptamer; Biosensors; Chemical sensors; Conductors; Electrochemical analysis; Electrochemical biosensor; Electrochemical impedance spectroscopy; Functional groups; Glassy carbon; Graphene; Oxidation; Oxide coatings; PTCA; Reduced graphene oxide; Self-assembly; Structural integrity; Thin films; Thrombin; Thrombin; Self-assembly; Aptamer; Electrochemical biosensor; Reduced graphene oxide; PTCA
• ISSN: 0257-8972; 1879-3347
• DOI: 10.1016/j.surfcoat.2020.126491

Graphene-based thin film has been widely used as signal conductor and platform material in electrochemical sensors. For commonly used reduced graphene oxide (rGO), oxygen-containing functional groups can provide coupling sites to conjugate with bio-cognitive elements, but high degree of oxidation can harm its structural integrity and signal conductivity. In this work, a new strategy is developed to balance the conductivity and functionality of rGO. The PTCA-rGO composite film was prepared by self-assembly and used to fabricate electrochemical biosensor. To form reusable thrombin aptasensor, an in situ layer-by-layer self-assembling method was adopted to stepwise deposit reduced graphene oxide (rGO), 3, 4, 9, 10-perylenetetracarboxylic acid (PTCA), and thrombin aptamer (TBA) onto 3-aminopropyltriethoxy silane (APTES)-modified glassy carbon electrode (GCE). The as-prepared aptasensor was used to determine thrombin in response to impedimetric signal by electrochemical impedance spectroscopy (EIS). The as-prepared GCE/rGO/PTCA/TBA sensor provided outstanding performance for determination of thrombin concentration with wide linear range (1 pM-100 nM), low detection limit (0.2 pM), reusability, and good specificity to thrombin. The good performance of GCE/rGO/PTCA/TBA aptasensor can be attributed to the electrochemical property of rGO-PTCA composite film and the in situ layer-by-layer fabricated strategy. This PTCA-modification method is promising to be widely used in the fabrication of graphene-based electrochemical devices. •A self-assembling method is adopted to deposit PTCA-rGO film on GCE.•The GCE/rGO/PTCA/TBA sensor exhibits outstanding performance for thrombin sensing.•The as-prepared sensor shows wide linear range, low detection limit, and ability to reuse.•The PTCA-modification of graphene provides both good conductivity and functionality.