title: Simultaneous electrochemical detection of multiple analytes based on dual signal amplification of single-walled carbon nanotubes and multi-labeled graphene sheets.
abstract: In this work, a sandwich-type electrochemical aptasensor for simultaneous sensitive detection of platelet-derived growth factor (PDGF) and thrombin is fabricated. Reduced graphene oxide sheets (rGS) are used as matrices to immobilize the redox probes, which are subsequently coated with platinum nanoparticles (PtNPs) to form the PtNPs-redox probes-rGS nanocomposites. With the employment of the as prepared nanocomposites, a signal amplification strategy was described based on bienzyme (glucose oxidase and horseradish peroxidase) modified PtNPs-redox probes-rGS nanocomposites as the tracer labels for secondary aptamers (Apt II) through sandwiched assay. Gold nanoparticles functionalized single-walled carbon nanotubes (AuNPs@SWCNTs) as the biosensor platform enhance the surface area to capture a large amount of primary aptamers (Apt I), thus amplifying the detection response. The experiment results show that the multi-labeled PtNPs-redox probes-rGS nanocomposites display satisfying electrochemical redox activity and highly electrocatalytic activity of PtNPs and bienzyme, which exhibit high sensitivity for detection of proteins. The linear range of PDGF is 0.01-35 nM with a detection limit of 8 pM, while the linear ranges from 0.02 to 45 nM and a detection limit of 11 pM for thrombin are obtained.
authors: Education Ministry Key Laboratory on Luminescence and Real-Time Analysis, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, PR China.
authors: Lijuan
authors: L
authors: Bai
authors: Ruo
authors: R
authors: Yuan
authors: Yaqin
authors: Y
authors: Chai
authors: Ying
authors: Y
authors: Zhuo
authors: Yali
authors: Y
authors: Yuan
authors: Yan
authors: Y
authors: Wang
mesh_terms: D052157:Aptamers, Nucleotide / Q000378:metabolism*; D015374:Biosensing Techniques / Q000379:methods; D055664:Electrochemical Techniques / Q000379:methods*; D006046:Gold / Q000737:chemistry; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D057230:Limit of Detection; D053761:Nanocomposites / Q000737:chemistry / Q000648:ultrastructure; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure; D010982:Platelet-Derived Growth Factor / Q000032:analysis* / Q000378:metabolism; D010984:Platinum / Q000737:chemistry; D013917:Thrombin / Q000032:analysis* / Q000378:metabolism
chemical_list: D052157:Aptamers, Nucleotide; D037742:Nanotubes, Carbon; D010982:Platelet-Derived Growth Factor; D010984:Platinum; D006046:Gold; D006108:Graphite; D013917:Thrombin