Photoelectrochemical Determination of Cardiac Troponin I as a Biomarker of Myocardial Infarction Using a Bi2S3 Film Electrodeposited on a BiVO4-Coated Fluorine-Doped Tin Oxide Electrode

• Published in: Biosensors (Basel) Vol. 13; no. 3; p. 379
• Main Authors: Monteiro, Thatyara Oliveira, Neto, Antônio Gomes dos Santos, de Menezes, Alan Silva, Damos, Flávio Santos, Luz, Rita de Cássia Silva, Fatibello-Filho, Orlando
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 13.03.2023; MDPI
• Subjects: Acids; Antibodies; Antigens; Ascorbic acid; Biomarkers; Bismuth; Bismuth oxides; bismuth sulfide; Bismuth sulfides; bismuth vanadate; Blood plasma; Calcium-binding protein; Chloride; Chromatography; cTnI; Electrodeposition; Electrodes; Fluorine; Heart; Heart attacks; Immunosensors; Myocardial infarction; Nitrates; PEC immunosensor; Photoelectric effect; Photoelectric emission; Potassium; Semiconductors; Sodium; Tin; Tin oxide; Tin oxides; Troponin I; Vanadate; Vanadates; Brazil
• ISSN: 2079-6374; 2079-6374
• DOI: 10.3390/bios13030379

A sensitive and selective label-free photoelectrochemical (PEC) immunosensor was designed for the detection of cardiac troponin I (cTnI). The platform was based on a fluorine-doped tin oxide (FTO)-coated glass photoelectrode modified with bismuth vanadate (BiVO4) and sensitized by an electrodeposited bismuth sulfide (Bi2S3) film. The PEC response of the Bi2S3/BiVO4/FTO platform for the ascorbic acid (AA) donor molecule was approximately 1.6-fold higher than the response observed in the absence of Bi2S3. The cTnI antibodies (anti-cTnI) were immobilized on the Bi2S3/BiVO4/FTO platform surface to produce the anti-cTnI/Bi2S3/BiVO4/FTO immunosensor, which was incubated in cTnI solution to inhibit the AA photocurrent. The photocurrent obtained by the proposed immunosensor presented a linear relationship with the logarithm of the cTnI concentration, ranging from 1 pg mL−1 to 1000 ng mL−1. The immunosensor was successfully employed in artificial blood plasma samples for the detection of cTnI, with recovery values ranging from 98.0% to 98.5%.