1. A Label-free Cardiac Troponin T Electrochemiluminescence Immunosensor Enhanced by Graphene Nanoplatelets
- Author
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Syazana Abdullah Lim, Nura Fazira Noor Azam, Nur Afina Mohammad, and Minhaz Uddin Ahmed
- Subjects
Working electrode ,Point-of-Care Systems ,chemistry.chemical_element ,Biosensing Techniques ,02 engineering and technology ,01 natural sciences ,Analytical Chemistry ,chemistry.chemical_compound ,Bipyridine ,Troponin T ,Troponin complex ,Limit of Detection ,Electrochemistry ,Humans ,Electrochemiluminescence ,Electrodes ,Immunoassay ,Detection limit ,Chemistry ,Myocardium ,010401 analytical chemistry ,Hydrogen-Ion Concentration ,021001 nanoscience & nanotechnology ,Nanostructures ,0104 chemical sciences ,Ruthenium ,Linear range ,Luminescent Measurements ,Luminophore ,Printing ,Graphite ,Adsorption ,0210 nano-technology ,Nuclear chemistry - Abstract
In this study, a direct and label-free immunosensor was designed and constructed by modifying the screen-printed electrode with graphene nanoplatelets (GNPs) for the detection of the cardiac troponin T (cTnT). Firstly, GNPs were drop-casted onto carbon working electrode. Monoclonal cTnT antibodies were then immobilized on the GNPs via physical adsorption; finally, BSA was introduced to block non-specific binding sites. The detection of cTnT was performed using an electrochemiluminescence (ECL) technique with tris(bipyridine)ruthenium(II) chloride ([Ru(bpy)3]Cl2) used as a luminophore and TPrA (tripropylamine) as a co-reactant. The ECL intensity was demonstrated to be directly proportional to the cTnT concentration where a linear range from 100 pg mL-1 to 5 fg mL-1 of the cTnT detection was established. An extremely low limit of detection was achieved to be 0.05 fg mL-1 with an outstanding specificity. Additionally, this immunosensor showed excellent percentage recovery for real samples analyses in artificially spiked human serum.
- Published
- 2019
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