title: Cross-talk-free multiplexed immunoassay using a disposable electrochemiluminescent immunosensor array coupled with a non-array detector.
abstract: A disposable electrochemiluminescent (ECL) immunosensor array was fabricated on a screen-printed carbon electrode (SPCE) substrate to perform multiplexed immunoassay (MIA) for the first time. The SPCE substrate was composed of an array of four carbon working electrodes, one common Ag/AgCl reference electrode, and one common carbon counter electrode. The immunosensor array was constructed by site-selectively immobilizing multiple antigens on different working electrodes of the SPCE substrate. With a competitive immunoassay format, the immobilized antigens competed with antigens in the sample to capture their corresponding tri(2,2'-bipyridyl)ruthenium(II)-labeled antibodies. The ECL signals from the immunosensors in this array were sequentially detected by a photomultiplier with the aid of a homemade single-pore-four-throw switch. Due to the ECL readout mechanism and the sequential detection mode, it could avoid the cross-talk between the adjacent immunosensors, which was common in other reported immunosensor array. Human, rabbit and mouse immunoglobulin Gs were near-simultaneously assayed as the model analytes. The linear ranges for them were 10-400, 20-400, and 20-400 ng/mL, with detection limits of 2.9, 6.1 and 6.5 ng/mL (S/N=3), respectively. This novel ECL strategy based on immunosensor array coupled with non-array detector provided a simple, sensitive, low-cost and time-saving approach for MIA. It showed great application potential in point-of-care test and field analysis of bio-agents, with mass production potential and high throughput.
authors.affiliation: Key Laboratory of Luminescence and Real-Time Analysis (Ministry of Education), College of Pharmaceutical Sciences, Southwest University, Chongqing, China.
authors.forename: Cuifang
authors.initials: C
authors.lastname: Li
authors.forename: Zhifeng
authors.initials: Z
authors.lastname: Fu
authors.forename: Zongyun
authors.initials: Z
authors.lastname: Li
authors.forename: Zhenxing
authors.initials: Z
authors.lastname: Wang
authors.forename: Wei
authors.initials: W
authors.lastname: Wei
mesh_terms: D015082:2,2'-Dipyridyl / Q000031:analogs & derivatives / Q000737:chemistry; D000818:Animals; D000941:Antigens / Q000276:immunology; D001667:Binding, Competitive; D015374:Biosensing Techniques; D002244:Carbon / Q000737:chemistry; D056831:Coordination Complexes; D006801:Humans; D007118:Immunoassay; D007074:Immunoglobulin G / Q000032:analysis* / Q000276:immunology; D008163:Luminescent Measurements / Q000379:methods*; D051379:Mice; D019095:Point-of-Care Systems; D040081:Protein Array Analysis / Q000379:methods*; D011817:Rabbits; D017975:Ruthenium Compounds
chemical_list: D015082:2,2'-Dipyridyl; D000941:Antigens; D002244:Carbon; D056831:Coordination Complexes; D007074:Immunoglobulin G; C547232:tris(2,2-bipyridine)-ruthenium(II); D017975:Ruthenium Compounds