Highly sensitive amperometric detection of cardiac troponin I using sandwich aptamers and screen-printed carbon electrodes.
In this study, we developed a sandwich aptamer-based screen-printed carbon electrode (SPCE) using chronoamperometry for the detection of cardiac troponin I (cTnI), one of the promising biomarkers for acute myocardial infarction (AMI). Disposable three-electrode SPCEs were manufactured using a screen printer, and various modifications such as electrodeposition of gold nanoparticles and electropolymerization of conductive polymers were performed. From the bare electrode to the aptamer-immobilized SPCE, all processes were monitored and analyzed via various techniques such as cyclic voltammetry, electrochemical impedance spectroscopy, and X-ray photoelectron spectroscopy. The quantification of cTnI was conducted based on amperometric signals from the catalytic reaction between hydrazine and H2O2. The fabricated aptasensor in a buffer, as well as in a serum-added solution, exhibited great analytical performance with a dynamic range of 1-100 pM (0.024-2.4ng/mL) and a detection limit of 1.0 pM (24pg/mL), which is lower than the existing cutoff values (40-700pg/mL). Furthermore, the developed sensor showed high sensitivity to cTnI over other proteins. It is anticipated that this potable SPCE aptasensor for cTnI will become an innovative diagnostic tool for AMI.
Department of Chemistry, Pohang University of Science and Technology, 77, Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk 790-784, South Korea. Electronic address: jhhsst@postech.ac.kr.
Hunho
H
Jo
Department of Chemistry, Pohang University of Science and Technology, 77, Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk 790-784, South Korea. Electronic address: jinh0902@postech.ac.kr.
Jin
J
Her
Department of Life Science, Pohang University of Science and Technology, 77, Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk 790-784, South Korea. Electronic address: delighthyun@postech.ac.kr.
Heehyun
H
Lee
Department of Chemistry, Pusan National University, Keumjeong-Ku, Busan 609-735, South Korea. Electronic address: ybshim@pusan.ac.kr.
Yoon-Bo
YB
Shim
Department of Chemistry, Pohang University of Science and Technology, 77, Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk 790-784, South Korea. Electronic address: ciban@postech.ac.kr.
Changill
C
Ban
D052157:Aptamers, Nucleotide / Q000737:chemistry*; D015374:Biosensing Techniques / Q000379:methods*; D002244:Carbon / Q000737:chemistry*; D055664:Electrochemical Techniques / Q000379:methods*; D004566:Electrodes; D006801:Humans; D057230:Limit of Detection; D019210:Troponin I / Q000032:analysis*
D052157:Aptamers, Nucleotide; D019210:Troponin I; D002244:Carbon
Aptamer; Cardiac troponin I; Chronoamperometry; Diagnosis; Hydrazine; Screen-printed carbon electrode