The Role of a Semiconductor Chalcogenide in a Label-Free Aptasensor for Detection of Ultra-Trace amounts of Aflatoxin B۱ in Wheat Flour

Addressed herein, Bismuth sulfide (Bi۲S۳) as a synthetic semiconductor chalcogenide applied in fabrication process of an aptasensor as a signal promoter for ultra-trace detection of aflatoxin B۱(AFB۱). The analytical signal was improved by using optimized amounts of Bi۲S۳ for electrode modification. The AFB۱ 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 AFB۱(۰.۳-۶۳۰nM) was supported by the fabricated aptasensor (pencil/polydopamine@Bi۲S۳/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(۰.۰۴nM) with a great sensitivity (۰.۰۷۶µA/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.

کلیدواژه ها:

Aptasensor ، Aflatoxin B۱ ، Bismuth sulfide ، Pencil electrode ، Polydopamine