Zahra Fahraji - Department of Biology, Medical Biotechnology Research Center, Ashkezar Branch, Islamic Azad University, Ashkezar, Yazd, Iran
Navid Nasirizadeh - Department of Textile and Polymer Engineering, Yazd Branch, Islamic Azad University, Yazd, Iran
Seyed Morteza Seifati - Department of Biology, Medical Biotechnology Research Center, Ashkezar Branch, Islamic Azad University, Ashkezar, Yazd, Iran
Mostafa Azimzadeh - Stem Cell Biology Research Center, Yazd Reproductive Sciences Institute, Shahid Sadoughi University of Medical Sciences, P. O. Box: ۸۹۱۹۵-۹۹۹, Yazd, Iran. Department of Advanced Medical Sciences and Technologies, School of

Bacterial infection is a global problem, and detection of bacteria is the first step for solving such a problem. Herein, we developed an electrochemical biosensor for the detection of the bacteria Chlamydia Trachomatis. The hybridization-based biosensor was made by modifying the screen-printed gold electrode (SPGE) with the thiolated specific detection probes, which were complementary sequences to the target DNA molecule of the bacteria. The Oracet blue was used as an electrochemical label which was intercalated between two DNA sequences, and its reduction peak current was recorded by DPV method as an output signal of the biosensor. Conventional electrochemical characterization techniques, including cyclic voltammetry (CV) and Electrochemical impedance spectroscopy (EIS), were used to confirm the fabrication of the modified electrode. In addition, the Atomic Force Microscopy (AFM) imaging was performed to assess the electrode surface. The dynamic range of the biosensor was from ۴ to ۳۰۰۰ pM with a detection limit of ۱.۳ pM. The simplicity and performance mentioned above of the biosensor, alongside the low cost and repeatability of the production, make it a great candidate for clinical applications for Chlamydia Trachomatis detection. Plus, it can be used for another species of bacteria with just a change of the thiolated probe.

Electrochemical sensor, Bacteria, Detection, DNA, Chlamydia trachomatis