title: Ultrasensitive simultaneous detection of four biomarkers based on hybridization chain reaction and biotin-streptavidin signal amplification strategy.
abstract: A sandwich-type electrochemical immunosensor based on redox probe tags identification technology for ultrasensitive simultaneous detection of four antigens was proposed. In this project, well-distributed graphene/gold (GR-Au) hybrid film was acquired through one-step codeposition in an electrode surface and served as the base substrate for immobilizing capture antibodies (Ab1). Hybridization chain reaction (HCR) and biotin/streptavidin (B/SA), combining with gold magnetic nanoparticles were applied to increase the immobilization amount of signal tags in detection antibody (Ab2) bioconjugates. To verify this strategy, four representative biomarkers, a-fetoprotein (AFP), carcinoembryonic antigen (CEA), carbohydrate antigen (CA)125 and prostate special antigen (PSA), were used as model analytes. The resulting immunosensor could simultaneously detect four antigens in single-pass differential pulse voltammetry (DPV) scan, and exhibited obviously improved senstivity compared to previous similar immunosensors, displayed good linear relationships in the ranges from 0.2 to 800 pg/mL for AFP, 0.2 to 600 pg/mL for CEA, 0.2 to 1000 pg/mL for CA125, 0.2 to 800 pg/mL for PSA and with detection limits of 62, 48, 77 and 60 fg/mL, respectively.
authors.affiliation: Key Laboratory on Luminescence and Real-Time Analysis, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China; College of Chemistry, Chongqing Normal University, Chongqing 400047, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhu
authors.affiliation: Key Laboratory on Luminescence and Real-Time Analysis, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China. Electronic address: yqchai@swu.edu.cn.
authors.forename: Yaqin
authors.initials: Y
authors.lastname: Chai
authors.affiliation: Key Laboratory on Luminescence and Real-Time Analysis, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhuo
authors.affiliation: Key Laboratory on Luminescence and Real-Time Analysis, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China. Electronic address: yuanruo@swu.edu.cn.
authors.forename: Ruo
authors.initials: R
authors.lastname: Yuan
mesh_terms: D015374:Biosensing Techniques; D018394:CA-125 Antigen / Q000737:chemistry / Q000302:isolation & purification*; D002272:Carcinoembryonic Antigen / Q000737:chemistry / Q000302:isolation & purification*; D048271:Chitosan / Q000737:chemistry; D006046:Gold / Q000737:chemistry; D006108:Graphite / Q000737:chemistry; D055767:Immobilized Proteins / Q000737:chemistry / Q000276:immunology; D058185:Magnetite Nanoparticles / Q000737:chemistry; D009693:Nucleic Acid Hybridization; D017430:Prostate-Specific Antigen / Q000737:chemistry / Q000302:isolation & purification*; D000509:alpha-Fetoproteins / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D018394:CA-125 Antigen; D002272:Carcinoembryonic Antigen; D055767:Immobilized Proteins; D058185:Magnetite Nanoparticles; D000509:alpha-Fetoproteins; D006046:Gold; D006108:Graphite; D048271:Chitosan; D017430:Prostate-Specific Antigen
keywords: Biotin/streptavidin; Graphene/gold hybrid film; Hybridization chain reaction; Redox probe; Simultaneous multi-analytes detection