Immobilized Reporter Phage on Electrospun Polymer Fibers for Improved Capture and Detection of Escherichia coli O157:H7

Abstract

Escherichia coli O157:H7 is a foodborne Shiga-toxin-producing bacterium that leads to millions of cases of illness every year. The development of a portable biosensor that rapidly detects this pathogen can greatly reduce both the time required to identify the source of contamination within the food production chain and the scale of outbreaks. Here we propose a swab for the detection of E. coli O157:H7 made from electrospun poly-3-hydroxybutyrate (PHB) on which the reporter bacteriophage (phage), PP01engineered to express the bioluminescent protein Nanoluc upon infection of the pathogenhas been immobilized. In the development of the material, the properties of phage-immobilized electrospun porous, nonwoven PHB mats were compared to those of phage-immobilized flat PHB films produced by solvent casting. Dynamics of E. coli infections initiated with the phage-immobilized materials showed the electrospun mats had the highest infectivity, indicative of higher phage surface density (confirmed by microscopy) and activitytwo important properties for the sensitivity and response time of biosensors. In sample tests, successful detection of E. coli O157:H7 cells in both milk and Tryptic Soy Broth at concentrations of 105 CFU/mL within 1 h and 101 CFU/mL within 3 h demonstrates the promising potential of the system as a food safety assessment tool.

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“…The release of phages through, e.g., fiber expansion or dissolution of the polymer is controlled by the selection of appropriate materials (e.g., mixed fiber polymers). The disadvantage of this system is the possibility of destruction of the phage as a result of rapid dehydration during electrospinning [134][135][136].…”

Recent advances in bacteriophage-based therapeutics: Insight into the post-antibiotic era

“…4 A). The “bioactive surfaces” not only target and inactivate bacterial pathogens, but also allow the detection, identification, and phage-mediated immobilization of targeted microbes 52 , 53 . The advantage of electrospun fibers is that they allow for the controlled release of phage particles, which is controlled by the selection of materials.…”

Functionalized-Graphene Field Effect Transistor-Based Biosensor for Ultrasensitive and Label-Free Detection of β-Galactosidase Produced by Escherichia coli

“…Currently, various sensitive analytical methods, including electrochemistry, bioluminescence, dynamic light scattering (DLS), and surface plasmon resonance (SPR) are available for β-gal and E. coli quantitative detection in different samples [6,[9][10][11][12][13][14][15][16][17][18]. Olivier Laczka et al have proposed the efficiency of methodologies for the detection of enteric pathogens, based on the amperometric detection of β-gal activity.…”