title: Performance characteristics of monoclonal antibodies as recyclable binders to cardiac troponin I.
abstract: Acute myocardial infarction is a typical disorder that requires continuous monitoring for early detection of potential life-threatening situations. To this end, we used different methods to screen for rapidly reversible antibodies, among 22 hybridoma clones, against cardiac troponin I (cTnI), which is a specific marker indicating the disease. The dissociation rates of antibodies were underestimated by up to a factor of 1000 because of bivalent binding when tested with the antigen immobilized on solid surfaces. This effect was also observed in a sandwich immunoassay, in which the detection antibody cross-linked with various antigen molecules already bound to the capture antibody. Although multiple binding events contributed to enhanced detection capability, it was difficult to recycle the immunosensor. We then devised a screening system by arranging the test antibody for the capture binder immobilized on a label-free sensor. This enabled us to select fast reactive antibodies of which one (clone 24) was shown to be recyclable, even in serum-containing medium. Using this antibody, repetitive detection of cTnI with a rapid response time (half-life of dissociation: about 4min on average) and high detection capability (0.1ng/ml) was achieved, which is very important for detection in a clinical setting.
authors.affiliation: Department of Bio-Microsystem Technology, Korea University, Sungbuk-gu, Seoul 136-701, Republic of Korea.
authors.forename: Dong-Hyung
authors.initials: DH
authors.lastname: Kim
authors.forename: Sung-Ho
authors.initials: SH
authors.lastname: Paek
authors.forename: Guei-Sam
authors.initials: GS
authors.lastname: Lim
authors.forename: Jin-Woo
authors.initials: JW
authors.lastname: Jeon
authors.forename: Se-Hwan
authors.initials: SH
authors.lastname: Paek
mesh_terms: D055910:Antibodies, Immobilized / Q000737:chemistry / Q000276:immunology; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000936:Antigen-Antibody Complex; D015374:Biosensing Techniques; D006207:Half-Life; D006801:Humans; D007118:Immunoassay; D007700:Kinetics; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation; D009206:Myocardium / Q000378:metabolism*; D019210:Troponin I / Q000097:blood* / Q000276:immunology
chemical_list: D055910:Antibodies, Immobilized; D000911:Antibodies, Monoclonal; D000936:Antigen-Antibody Complex; D019210:Troponin I