Development of an amperometric biosensor for the detection of Bacillus anthracis spores

•We developed a screen-printed electrode and magnetic bead-based amperometric electrochemical immunosensor for rapid and specific detection of B. anthracis spores.•This method measures changes in current intensity resulting from oxidation and reduction in the working electrode directly to the spore concentrations.•Optimization of newly developed biosensor was performed by using tests with inactive and active spore measurements.•Our results may lead an essential basis for developing Point-of-care (POC) devices that allow on-site and early detection of B. anthracis spores, which are also considered as a biological warfare agent. Due to most likely use of Bacillus anthracis in biological terrorism agents, the rapid and sensitive detection of its spores is crucial in both taking prophylactic measures and proper treatment. This study aimed to develop an amperometric electrochemical immunosensor for the detection of B. anthracis spores. A new amperometric biosensor was designed using a combination of magnetic beads and multiplex screen-printed electrodes. This method measures changes in current intensity resulting from oxidation and reduction in the working electrode directly to spore concentrations. A standard curve was formed to test the number of live spores between 2 × 102-2 × 104 spores/ml concentrations. LOD and LOQ values were found to be 92 and 272 spores/ml, respectively. No cross-reactions were seen for Bacillus subtilis, Bacillus cereus and Bacillus thuringiencis spores. It is shown that the designed Anthrax immunosensor has high sensitivity and selectivity with rapid detection results.