title: Ionic liquid functionalized graphene/Au nanocomposites and its application for electrochemical immunosensor.
abstract: In this work, a new nanocomposite, which was composed of ionic liquid functionalized graphene sheet (IL-GS) loaded gold nanoparticles (AuNPs), was prepared. The IL-GS was directly synthesized by the electrochemical exfoliation of graphite in ionic liquid (IL). Due to the modification of the IL, IL-GS can not only be dispersed easily in aqueous solution to form a homogeneous colloidal suspension of individual sheet, but also exhibits an improved conductivity. Meanwhile, the loaded AuNPs on the nanocomposites can increase the specific surface area to capture a large amount of antibodies as well as improve the capability of electron transfer. The IL-GS-Au nanocomposites were successfully employed for the fabrication of a facile and sensitive electrochemical immunosensor. Carcinoembryonic antigen (CEA) was used as a model protein. The proposed immunosensor exhibits a wide linear detection range (LDR) from 1 fg mL⁻¹ to 100 ng mL⁻¹, and an ultralow limit of detection (LOD) of 0.1 fg mL⁻¹ (S/N=3). In addition, for the detection of clinical serum samples, it is well consistent with the data determined by the developed immunoassay and ELISA, indicating that the immunosensor provides a possible application for the detection of CEA in clinical diagnostics.
authors: College of Life Science, Capital Normal University, Beijing 100048, China.
authors: Na
authors: N
authors: Liu
authors: Xia
authors: X
authors: Chen
authors: Zhanfang
authors: Z
authors: Ma
mesh_terms: D055910:Antibodies, Immobilized / Q000737:chemistry; D015374:Biosensing Techniques / Q000379:methods; D002272:Carcinoembryonic Antigen / Q000097:blood*; D055664:Electrochemical Techniques / Q000379:methods*; D006046:Gold / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D007118:Immunoassay / Q000379:methods; D052578:Ionic Liquids / Q000737:chemistry*; D057230:Limit of Detection; D053761:Nanocomposites / Q000737:chemistry*
chemical_list: D055910:Antibodies, Immobilized; D002272:Carcinoembryonic Antigen; D052578:Ionic Liquids; D006046:Gold; D006108:Graphite