Document Type : Full research article

Authors

• Amirkhosro Beheshti
• Sayed Zia Mohammadi
• Mahdokht Arjmand Kermani
• Tahereh Rohani

Department of Chemistry, Payame Noor University, 19395-4697, Tehran, Iran

Abstract

Addressed herein, Bismuth sulfide (Bi₂S₃) as a synthetic semiconductor chalcogenide applied in fabrication process of an aptasensor as a signal promoter for ultra-trace detection of aflatoxin B1(AFB1). The analytical signal was improved by using optimized amounts of Bi₂S₃ for electrode modification. The AFB1 Aptamer single strand type(SSDNA) was simply immobilized on the cross section of a pencil lead through polydopamine layers. A wide concentration range of trace amounts of AFB1(0.3-630nM) was supported by the fabricated aptasensor (pencil/polydopamine@Bi₂S₃/aptamer) using differential pulse voltammetry. Simple fabrication and no needing to electrode refreshment were part of the advantages of the suggested aptasensor. Finally, very low resulted detection limit(0.04nM) with a great sensitivity (0.076µA/nM) and also appropriate stability and repeatability led to application of the aptasensor in real sample analysis such as wheat flour with brilliant recovery percentages.

Keywords

• Aptasensor
• Aflatoxin B1
• Bismuth sulfide
• Pencil electrode
• Polydopamine