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Title: Electrochemical Sensors Based on MoS x ‐Functionalized Laser‐Induced Graphene for Real‐Time Monitoring of Phenazines Produced by Pseudomonas aeruginosa

Pseudomonas aeruginosa(P. aeruginosa) is an opportunistic pathogen causing infections in blood and implanted devices. Traditional identification methods take more than 24 h to produce results. Molecular biology methods expedite detection, but require an advanced skill set. To address these challenges, this work demonstrates functionalization of laser‐induced graphene (LIG) for developing flexible electrochemical sensors forP. aeruginosabased on phenazines. Electrodeposition as a facile approach is used to functionalize LIG with molybdenum polysulfide (MoSx). The sensor's limit of detection (LOD), sensitivity, and specificity are determined in broth, agar, and wound simulating medium (WSM). Control experiments withEscherichia coli, which does not produce phenazines, demonstrate specificity of sensors forP. aeruginosa. The LOD for pyocyanin (PYO) and phenazine‐1‐carboxylic acid (PCA) is 0.19 × 10−6 and 1.2 × 10−6 m, respectively. Furthermore, the highly stable sensors enable real‐time monitoring ofP. aeruginosabiofilms over several days. Comparing square wave voltammetry data over time shows time‐dependent generation of phenazines. In particular, two configurations—“Normal” and “Flipped”—are studied, showing that the phenazines time dynamics vary depending on how cells interact with sensors. The reported results demonstrate the potential of the developed sensors for integration with wound dressings for early diagnosis ofP. aeruginosainfection.

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Award ID(s):
Author(s) / Creator(s):
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Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Healthcare Materials
Medium: X
Sponsoring Org:
National Science Foundation
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    Y. Lei, D. Butler, M. C. Lucking, F. Zhang, T. Xia, K. Fujisawa, T. Granzier-Nakajima, R. Cruz-Silva, M. Endo, H. Terrones, M. Terrones, A. Ebrahimi,Sci. Adv.6, 4250–4257 (2020).

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    T. Wu, A. Alharbi, R. Kiani, D. Shahrjerdi,Adv. Mater.31, 1–12 (2019).

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