Optical Fiber Biosensor toward E-coli Bacterial Detection on the Pollutant Water

The antibody immobilization with low-cost materials and label-free methods are a challenge for the fabrication of biosensor devices. In this work, it was developed a strategy for antibody immobilization on ZnO TFTs over polyethylene terephthalate (PET) as a recyclable plastic substrate. Antibodies were biofunctionalized using a label-free strategy for E. coli detection. The use of a recyclable plastic substrate PET enables the compatibility with flexible electronics that could contribute for a low-cost biosensor useful in rural communities that do not have the necessary infrastructure and trained personnel for pathogenic bacterial detection in food or water.

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A novel method for sensitive detection of Escherichia coli O157:H7 based on an aptamer and hybridization chain reaction

Analytical Methods ◽

10.1039/d0ay00708k ◽

2020 ◽

Vol 12 (29) ◽

pp. 3734-3740

Author(s):

Yuexin Liu ◽

Ping Chen ◽

Shuai Yuan ◽

Bo Sun ◽

Rui Sun ◽

...

Keyword(s):

Escherichia Coli ◽

Sensitive Detection ◽

Hybridization Chain Reaction ◽

Escherichia Coli O157 ◽

Chain Reaction ◽

Bacterial Detection ◽

E Coli ◽

Novel Method

A novel assay for the sensitive detection of E. coli O157:H7 using an aptamer-based HCR, which provided a universal platform for other bacterial detection.

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Immunomagnetic Separation in Microchannels: From MEMS to BioNEMS

Microelectromechanical Systems ◽

10.1115/imece2005-81569 ◽

2005 ◽

Cited By ~ 1

Author(s):

Ashok Sinha ◽

Ranjan Ganguly ◽

Ishwar K. Puri

Keyword(s):

Pathogenic Bacteria ◽

Pathogen Detection ◽

Immunomagnetic Separation ◽

Detection Methods ◽

Contaminated Water ◽

Selective Detection ◽

Bacterial Detection ◽

E Coli ◽

Biological Environment ◽

Innovative Concept

Conventional methods of monitoring and testing water quality involve collection of the sample to be tested and its subsequent analysis in a research laboratory for which some procedures may not be feasible or even accessible under certain field situations. Therefore, next generation sensors are required. Herein, an innovative concept that combines a micromixer and microparticle trap is proposed that should enable more rapid pathogen detection in contaminated water. In it, immunomagnetic separation (a procedure [1,2] that is well practiced in the field of immunochemistry) is scaled down from the benchtop to the microscale. Our design is generic, i.e., design is not limited to the detection of waterborne biological agents, but can be used for other forms of chemical analysis. Testing for waterborne bacteria requires analysis methods that must meet a number of challenging criteria. Time and sensitivity of analysis are the more important limitations. Bacterial detection methods have to be rapid and very sensitive since the presence of even a small pathogenic sample may sometimes constitute an infectious or otherwise harmful dose. Selective detection is also required because small numbers of pathogenic bacteria are often present in a complex biological environment along with many other nonpathogenic organisms. As an example, the infectious dosage of a pathogen such as E. coli O157:H7 or Salmonella is as low as 10 cells and the existing coliform standard for E. coli in water is 4 cells: 100 ml [3].

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Repetitive Detection of Aromatic Hydrocarbon Contaminants with Bioluminescent Bioreporters Attached on Tapered Optical Fiber Elements

Sensors ◽

10.3390/s20113237 ◽

2020 ◽

Vol 20 (11) ◽

pp. 3237

Author(s):

Jakub Zajíc ◽

Steven Ripp ◽

Josef Trögl ◽

Gabriela Kuncová ◽

Marie Pospíšilová

Keyword(s):

Aromatic Hydrocarbon ◽

Optical Fiber ◽

Pseudomonas Putida ◽

Nutrient Medium ◽

Cell Layer ◽

Optical Probe ◽

E Coli ◽

Toluene Concentration ◽

Tapered Optical Fiber ◽

Fiber Element

In this study, we show the repetitive detection of toluene on a tapered optical fiber element (OFE) with an attached layer of Pseudomonas putida TVA8 bioluminescent bioreporters. The bioluminescent cell layer was attached on polished quartz modified with (3-aminopropyl)triethoxysilane (APTES). The repeatability of the preparation of the optical probe and its use was demonstrated with five differently shaped OFEs. The intensity of measured bioluminescence was minimally influenced by the OFE shape, possessing transmittances between 1.41% and 5.00%. OFE probes layered with P. putida TVA8 were used to monitor liquid toluene over a two-week period. It was demonstrated that OFE probes layered with positively induced P. putida TVA8 bioreporters were reliable detectors of toluene. A toluene concentration of 26.5 mg/L was detected after <30 min after immersion of the probe in the toluene solution. Additional experiments also immobilized constitutively bioluminescent cells of E. coli 652T7, on OFEs with polyethyleneimine (PEI). These OFEs were repetitively induced with Lauria-Bertani (LB) nutrient medium. Bioluminescence appeared 15 minutes after immersion of the OFE in LB. A change in pH from 7 to 6 resulted in a decrease in bioluminescence that was not restored following additional nutrient inductions at pH 7. The E. coli 652T7 OFE probe was therefore sensitive to negative influences but could not be repetitively used.

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Detection of Escherichia coli O157:H7 in 10- and 25-Gram Ground Beef Samples with an Evanescent-Wave Biosensor with Silica and Polystyrene Waveguides

Journal of Food Protection ◽

10.4315/0362-028x-65.4.596 ◽

2002 ◽

Vol 65 (4) ◽

pp. 596-602 ◽

Cited By ~ 69

Author(s):

DANIEL R. DeMARCO ◽

DANIEL V. LIM

Keyword(s):

Escherichia Coli ◽

Optical Fiber ◽

Evanescent Wave ◽

Ground Beef ◽

False Positives ◽

Evanescent Field ◽

Escherichia Coli O157 ◽

Fiber Probe ◽

Fluorescent Signal ◽

E Coli

A portable evanescent-wave fiber-optic biosensor was used to detect Escherichia coli O157:H7 in seeded 10- and 25-g ground beef samples. The biosensor works by launching light from a 635-nm laser diode into specially designed optical fiber probes, generating an evanescent field that extends approximately 1,000 nm from the fiber surface. Fluorescent molecules within the evanescent field are excited, and a portion of their emission recouples into the fiber probe. The return path emission is transported by an optical fiber to a photodiode within the biosensor that detects and quantifies the fluorescent signal. A sandwich immunoassay was performed on the fiber probes with cyanine 5 dye–labeled polyclonal anti–E. coli O157:H7 antibodies for generation of the specific fluorescent signal. Biotin-streptavidin interactions were used to attach polyclonal antiE. coli O157:H7 antibodies to the surface of the fiber probe. A centrifugation method was developed to obtain samples suitable for biosensor analysis from 10- and 25-g ground beef samples. The assay was shown to be sensitive and repeatable. One hundred percent correct identification of positive samples was demonstrated at 9.0 × 103 CFU/g for 25-g ground beef samples with silica waveguides and at 5.2 × 102 CFU/g for 10-g ground beef samples with polystyrene waveguides. The reaction was highly specific. No false positives were observed for 10-g ground beef samples not spiked with the pathogen. In addition, when samples were spiked with high concentrations of a variety of non–E. coli O157:H7 organisms, no false positives were observed. The method was rapid, with results being obtained within 25 min of sample processing.

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Bacterial detection using carbohydrate-functionalised CdS quantum dots: a model study exploiting E. coli recognition of mannosides

Tetrahedron Letters ◽

10.1016/j.tetlet.2008.12.029 ◽

2009 ◽

Vol 50 (8) ◽

pp. 886-889 ◽

Cited By ~ 83

Author(s):

Balaram Mukhopadhyay ◽

Maristela B. Martins ◽

Rositsa Karamanska ◽

David A. Russell ◽

Robert A. Field

Keyword(s):

Quantum Dots ◽

Cds Quantum Dots ◽

Bacterial Detection ◽

E Coli ◽

Model Study

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A Galactosidase-Activatable Fluorescent Probe for Detection of Bacteria Based on BODIPY

Molecules ◽

10.3390/molecules26196072 ◽

2021 ◽

Vol 26 (19) ◽

pp. 6072

Author(s):

Xi Chen ◽

Yu-Cong Liu ◽

Jing-Jing Cui ◽

Fang-Ying Wu ◽

Qiang Xiao

Keyword(s):

Food Safety ◽

Fluorescent Probe ◽

Pathogen Detection ◽

Sensitive Detection ◽

Foodborne Diseases ◽

Bacterial Detection ◽

E Coli ◽

Enzyme Substrate

Pathogenic E. coli infection is one of the most widespread foodborne diseases, so the development of sensitive, reliable and easy operating detection tests is a key issue for food safety. Identifying bacteria with a fluorescent medium is more sensitive and faster than using chromogenic media. This study designed and synthesized a β-galactosidase-activatable fluorescent probe BOD-Gal for the sensitive detection of E. coli. It employed a biocompatible and photostable 4,4-difluoro-3a,4a-diaza-s-indancene (BODIPY) as the fluorophore to form a β-O-glycosidic bond with galactose, allowing the BOD-Gal to show significant on-off fluorescent signals for in vitro and in vivo bacterial detection. This work shows the potential for the use of a BODIPY based enzyme substrate for pathogen detection.

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Long-Period Gratings and Microcavity In-Line Mach Zehnder Interferometers as Highly Sensitive Optical Fiber Platforms for Bacteria Sensing

Sensors ◽

10.3390/s20133772 ◽

2020 ◽

Vol 20 (13) ◽

pp. 3772 ◽

Cited By ~ 1

Author(s):

Tinko Eftimov ◽

Monika Janik ◽

Marcin Koba ◽

Mateusz Śmietana ◽

Predrag Mikulic ◽

...

Keyword(s):

Optical Fiber ◽

Outer Membrane Proteins ◽

Label Free ◽

Fiber Sensors ◽

E Coli ◽

Long Period ◽

Long Period Gratings ◽

Highly Sensitive ◽

Micro Cavity ◽

And Staphylococcus Aureus

Selected optical fiber sensors offer extraordinary sensitivity to changes in external refractive (RI), which make them promising for label-free biosensing. In this work the most sensitive ones, namely long-period gratings working at (DTP-LPG) and micro-cavity in-line Mach-Zehnder interferometers (µIMZI) are discussed for application in bacteria sensing. We describe their working principles and RI sensitivity when operating in water environments, which is as high as 20,000 nm/RIU (Refractive index unit) for DTP-LPGs and 27,000 nm/RIU for µIMZIs. Special attention is paid to the methods to enhance the sensitivity by etching and nano-coatings. While the DTP-LPGs offer a greater interaction length and sensitivity to changes taking place at their surface, the µIMZIs are best suited for investigations of sub-nanoliter and picoliter volumes. The capabilities of both the platforms for bacteria sensing are presented and compared for strains of Escherichia coli, lipopolysaccharide E. coli, outer membrane proteins of E. coli, and Staphylococcus aureus. While DTP-LPGs have been more explored for bacteria detection in 102–106 Colony Forming Unit (CFU)/mL for S. aureus and 103–109 CFU/mL for E. coli, the µIMZIs reached 102–108 CFU/mL for E. coli and have a potential for becoming picoliter bacteria sensors.

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A plastic optical fiber biosensor for e. coli

10.1117/12.2177246 ◽

2015 ◽

Author(s):

Domingos M. C. Rodrigues ◽

Regina C. S. B. Allil ◽

Vanessa M. Queiroz ◽

Rafaela N. Lopes ◽

Alexandre Silva Allil ◽

...

Keyword(s):

Optical Fiber ◽

Plastic Optical Fiber ◽

E Coli

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Endotoxin Alteration of the Mucopolysaccharide Blood Vessel Coating in Rats

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100050755 ◽

1974 ◽

Vol 32 ◽

pp. 148-149

Author(s):

D. E. Philpott ◽

A. Takahashi

Keyword(s):

Skeletal Muscle ◽

Endothelial Cells ◽

Salivary Gland ◽

Carotid Artery ◽

Basement Membrane ◽

Coronary Vessels ◽

Ruthenium Red ◽

E Coli ◽

Old Rats ◽

The Brain

Two month, eight month and two year old rats were treated with 10 or 20 mg/kg of E. Coli endotoxin I. P. The eight month old rats proved most resistant to the endotoxin. During fixation the aorta, carotid artery, basil arartery of the brain, coronary vessels of the heart, inner surfaces of the heart chambers, heart and skeletal muscle, lung, liver, kidney, spleen, brain, retina, trachae, intestine, salivary gland, adrenal gland and gingiva were treated with ruthenium red or alcian blue to preserve the mucopolysaccharide (MPS) coating. Five, 8 and 24 hrs of endotoxin treatment produced increasingly marked capillary damage, disappearance of the MPS coating, edema, destruction of endothelial cells and damage to the basement membrane in the liver, kidney and lung.

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