title: Novel potentiometry immunoassay with amplified sensitivity for diphtheria antigen based on Nafion, colloidal Ag and polyvinyl butyral as matrixes.
abstract: A novel potentiometry immunoassay with amplified sensitivity has been developed for the detection of diphtheria antigen (Diph) via immobilizing diphtheria antibody (anti-Diph) on a platinum electrode based on Nafion, colloidal Ag (Ag), and polyvinyl butyral (PVB) as matrixes in this study. The modified procedure was further characterized by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The influence and factors influencing the performance of resulting immunosensor were studied in detail. The resulting immunosensor exhibited sigmoid curve with log Diph concentrations, high sensitivity (51.4 mV/decade), wide linear range from 8 to 800 ng ml(-1) with a detection limit of 1.5 ng ml(-1), rapid potentiometric response (<3 min) and long-term stability (>6 months). Analytical results of clinical samples show that the developed immunoassay is comparable with the enzyme-linked immunosorbent assays (ELISAs) method, implying a promising alternative approach for detecting diphtheria antigen in the clinical diagnosis.
authors.affiliation: Chong Qing Key Laboratory of Analytical Chemistry, College of Chemistry and Chemical Engineering, Southwest China Normal University, Chongqing 400715, China.
authors.forename: Dianping
authors.initials: D
authors.lastname: Tang
authors.forename: Ruo
authors.initials: R
authors.lastname: Yuan
authors.forename: Yaqin
authors.initials: Y
authors.lastname: Chai
authors.forename: Linyan
authors.initials: L
authors.lastname: Zhang
authors.forename: Xia
authors.initials: X
authors.lastname: Zhong
authors.forename: Jianyuan
authors.initials: J
authors.lastname: Dai
authors.forename: Yan
authors.initials: Y
authors.lastname: Liu
mesh_terms: D000941:Antigens / Q000032:analysis* / Q000276:immunology*; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D004165:Diphtheria / Q000276:immunology*; D004563:Electrochemistry / Q000295:instrumentation / Q000379:methods*; D004566:Electrodes; D005465:Fluorocarbon Polymers / Q000737:chemistry*; D006801:Humans; D007118:Immunoassay / Q000295:instrumentation / Q000379:methods*; D011145:Polyvinyls / Q000737:chemistry*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012834:Silver / Q000737:chemistry*
chemical_list: D000941:Antigens; D005465:Fluorocarbon Polymers; D011145:Polyvinyls; C040402:perfluorosulfonic acid; D012834:Silver; C027464:polyvinylbutyral