A dual-signal ratiometric electrochemical aptasensor based on Thi/Au/ZIF-8 and catalytic hairpin assembly for ultra-sensitive detection of aflatoxin B1

• Published in: Mikrochimica acta (1966) Vol. 191; no. 5; p. 256
• Main Authors: Liu, Jiahui, Wan, Zhigang, Wang, Xinwei, Suo, Zhiguang, Liu, Yong, Wei, Min
• Format: Journal Article
• Language: English
• Published: Vienna Springer Vienna 01.05.2024; Springer Nature B.V
• Subjects: Aflatoxin B1; Aflatoxins; Analytical Chemistry; Arachis; Assembly; Black tea; Catalysis; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; DNA; Gold; Metal-organic frameworks; Microengineering; Nanochemistry; Nanomaterials; Nanotechnology; Original Paper; Phenothiazines; Redox reactions; Zeolites; Aflatoxin B1; Dual-signal; Thi/Au/ZIF-8; Electrochemical aptasensor; Catalytic hairpin assembly
• ISSN: 0026-3672; 1436-5073
• DOI: 10.1007/s00604-024-06323-2

A dual-signal ratiometric electrochemical aptasensor has been developed  for AFB1 detection using thionine/Au/zeolitic imidazolate framework-8 (Thi/Au/ZIF-8) nanomaterials and catalytic hairpin assembly (CHA) reaction. Thi/Au/ZIF-8 combined with DNA hairpin 2 (H2) was used as a signal probe. [Fe(CN) 6 ] 3−/4− was served as another signal probe, and the I Thi/Au/ZIF-8 /I [Fe(CN)6] 3−/4− ratio was for the first time utilized to quantify AFB1. AFB1-induced CHA was used to expand the ratio of electrical signals. In the presence of AFB1, H2/Thi/Au/ZIF-8 bound to the electrode via CHA, enhanced  the current signal of Thi/Au/ZIF-8. H2 contained the DNA phosphate backbone hindered [Fe(CN) 6 ] 3−/4− redox reaction and resulted in a lower [Fe(CN) 6 ] 3−/4− current signal. This aptasensor exhibited high specificity for AFB1, a linear range of 0.1 pg mL −1 to 100 ng mL −1 , and a detection limit of 0.089 pg mL −1 . It demonstrated favorable sensitivity, selectivity, stability, and repeatability. The aptasensor was suitable for detecting AFB1 in peanuts and black tea and holds potential for real sample applications. Graphical Abstract