Highly sensitive photoelectrochemical immunosensor based on anatase/rutile TiO2 and Bi2S3 for the zero-biased detection of PSA

• Published in: Journal of solid state electrochemistry Vol. 24; no. 8; pp. 1801 - 1809
• Main Authors: Monteiro, Thatyara Oliveira, dos Santos, Clenilton Costa, do Prado, Thiago Martimiano, Damos, Flávio Santos, Luz, Rita de Cássia Silva, Fatibello-Filho, Orlando
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.08.2020; Springer Nature B.V
• Subjects: Analytical Chemistry; Anatase; Antibodies; Antigens; Ascorbic acid; Bismuth sulfides; Blood plasma; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Condensed Matter Physics; Electrochemistry; Energy Storage; Fluorine; Immunosensors; Nanoparticles; Original Paper; Photoelectric effect; Photoelectric emission; Physical Chemistry; Rutile; Tin oxides; Titanium dioxide; nanoparticles; TiO; Bismuth sulfide; Photoelectrochemical immunosensor; PSA
• ISSN: 1432-8488; 1433-0768
• DOI: 10.1007/s10008-020-04637-8

A novel label-free photoelectrochemical immunosensor was developed for the determination of prostate-specific antigen (PSA) based on fluorine-doped tin oxide (FTO) electrode modified with anatase and rutile titanium dioxide nanoparticles (TiO 2(a-r) ) as a platform for the electrodeposition of bismuth sulfide (Bi 2 S 3 ). The photoelectrochemical response of the TiO 2(a-r) platform sensitized with Bi 2 S 3 for the ascorbic acid donor molecule (AA) was about 34-fold higher than that observed in the absence of Bi 2 S 3 . The Bi 2 S 3 /TiO 2(a-r) /FTO platform was modified with PSA antibodies to produce the anti-PSA/Bi 2 S 3 /TiO 2(a-r) /FTO immunosensor, which was incubated in solutions of PSA antigen to inhibit the photocurrent of the immunosensor for AA. The photocurrent of the anti-PSA/Bi 2 S 3 /TiO 2(a-r) /FTO immunosensor presented a linear relationship with the logarithm of the PSA concentration ranging from 1 pg mL −1 to 100 ng mL −1 with good sensitivity and a limit of detection of 0.870 pg mL −1 . The sensor was successfully employed for the determination of PSA in artificial blood plasma samples, with recoveries between 94.6 and 98.6%.