Amplification of electrochemical signal by a whole-cell redox reactivation module for ultrasensitive detection of pyocyanin

• Published in: Biosensors & bioelectronics 2017-12, Vol.98, p.338-344
• Main Authors: Yang, Yuan, Yu, Yang-Yang, Wang, Yan-Zhai, Zhang, Chun-Lian, Wang, Jing-Xian, Fang, Zhen, Lv, Huoyang, Zhong, Jian-Jiang, Yong, Yang-Chun
• Format: Article
• Language: English
• Subjects: Bioelectrochemistry; Biosensing Techniques; Biosensor; Electrochemical Techniques; Humans; Oxidation-Reduction; Pseudomonas aeruginosa; Pseudomonas aeruginosa - isolation & purification; Pseudomonas aeruginosa - pathogenicity; Pseudomonas Infections - diagnosis; Pseudomonas Infections - microbiology; Pyocyanin; Pyocyanine - chemistry; Pyocyanine - isolation & purification; Signal amplification
• ISSN: 0956-5663; 1873-4235
• DOI: 10.1016/j.bios.2017.07.008

A bioelectrochemical sensing system based on a novel whole-cell redox reactivation/cycling module for ultrasensitive detection of pyocyanin (the biomarker of Pseudomonas aeruginosa infections) was developed. The electroactive bacteria mediated redox reactivation module was constructed using Shewanella oneidensis MR-1 cells as the bioelectro-catalyst and lactate as the electron donor. It could regenerate reductive pyocyanin from its oxidative state, which enabled pyocyanin molecule repeatedly registered by the electrode. Uniquely, with this redox reactivation module, the electrochemical response of pyocyanin was amplified about 405 times (1.3 μA/nM vs. 3.2nA/nM). Thus, an ultrasensitive bioelectrochemical sensing system for pyocyanin quantification was developed by integrating the pyocyanin reactivation module with conventional electrochemical detection system. Remarkably, with this developed biosensing system, an extremely low LOD of 47±1pM was reached. Additionally, this biosensing system showed excellent resistance to interferences from human fluids or bacterial contamination. This work provided a simple, ultrasensitive and robust tool for pyocyanin detection, and more importantly, demonstrated a new dimension for electrochemical signal amplification in biosensing. [Display omitted] •A whole-cell redox reactivation module based on exoelectrogen was developed.•Whole-cell signal amplification for bioelectrochemical sensing was developed.•Pyocyanin detection was achieved by using this signal amplification strategy.•The electrochemical response of pyocyanin was amplified about 405 times.•An extremely low LOD of pM level for pyocyanin detection was obtained.