An SPR immunosensor for human cardiac troponin T using specific binding avidin to biotin at carboxymethyldextran-modified gold chip.
BACKGROUND
The cardiac troponin T (TnT) is a cardiospecific, highly sensitive marker for myocardial damage and is immediately released to bloodstream during the acute myocardial infarction (AMI). Surface plasmon resonance (SPR) immunosensor was developed for the quick detection of human cTnT in real time.


METHODS
An SPR sensor streptavidin terminated self-assembled monolayer, which was used to binding biotinylated anti troponin T monoclonal antibodies, was developed.


RESULTS
The cTnT was determined from successive injections with a linear range from 0.03 up to 6.5 ng/ml. The detection limit was 0.01 ng/ml corresponding to a resonant angle change of 1.28 millidegrees. The system presented a good repeatability with 3.4% of variation between run after regeneration of the coated surface with a solution of 1% SDS. The effects of blocking of non-specific adsorption using different solutions were studied. It was possible to measure the cTnT without dilution of the human serum with good specificity and reproducibility.


CONCLUSIONS
This sensor is practical and offer quick response in interval of 800 s.
Dutra
Rosa Fireman
RF
Departamento de Patologia, Instituto de Ciências Biológicas, Universidade de Pernambuco, Recife, Brasil, Rua Arnóbio Marques, 310, Santo Amaro, 50100-130. Recife, PE , Brazil.
Kubota
Lauro Tatsuo
LT
D000911:Antibodies, Monoclonal / Q000378:metabolism; D001360:Avidin / Q000737:chemistry* / Q000378:metabolism; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D001710:Biotin / Q000737:chemistry* / Q000378:metabolism; D003911:Dextrans / Q000737:chemistry; D006046:Gold / Q000737:chemistry; D006801:Humans; D007118:Immunoassay; D009206:Myocardium / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D015203:Reproducibility of Results; D019809:Streptavidin / Q000737:chemistry; D020107:Troponin T / Q000097:blood*
D000911:Antibodies, Monoclonal; D003911:Dextrans; D020107:Troponin T; D001360:Avidin; D001710:Biotin; D006046:Gold; D019809:Streptavidin; C014392:carboxymethyl dextran