A Portable Biosensing Device with Magnetic Separation and Quantum Dot Bead Labeling for Simple, Rapid, and Quantitative Detection of Salmonella Typhimurium

2020 ◽  
Vol 63 (6) ◽  
pp. 1947-1955
Author(s):  
Xinge Xi ◽  
Ronghui Wang ◽  
Ping Yao ◽  
Lan Yao ◽  
Steve Tung ◽  
...  
Keyword(s):  
Quantum Dot ◽  
Salmonella Typhimurium ◽  
Magnetic Separation ◽  
Fluorescence Detection ◽  
Pathogenic Bacteria ◽  
Economic Losses ◽  
Quantitative Detection ◽  
List Type ◽  
Control Module ◽  
Detection Chamber

HighlightsA portable biosensing device was designed, fabricated, and evaluated for Salmonella detection.A mixing, separation, and detection chamber (MSDC) was developed and used for Salmonella detection.The disposable MSDC prevented cross-contamination and reduced costs.The device was mostly automated for Salmonella detection and feasible for in-field applications.Abstract. Foodborne pathogenic bacteria have caused numerous illnesses and economic losses in the U.S. and the world. It is highly important for food industries to conduct in-field screening for pathogenic bacteria to ensure food safety. The objective of this study was to convert our previously developed optical biosensing method into a portable biosensing device to achieve simple, rapid, and quantitative detection of Salmonella Typhimurium. The device consisted of a control module, a magnetic separation module, and a fluorescence detection module. The bacteria sample, immuno-magnetic nanoparticles, and immuno-quantum dot beads were added into a mixing, separation, and detection chamber and were fully mixed in the control module. The sample was then moved to the magnetic separation module to automatically separate and concentrate the target bacteria. Finally, the fluorescence intensity was measured with the fluorescence detection module to determine the concentration of the target bacteria. The device was able to perform separation and detection of Salmonella with minimal manual operation with a detection limit of 5.4 × 102 CFU mL-1 in 1 h. The device also showed good specificity against four selected non-target bacteria. Keywords: Biosensing device, Fluorescence biosensor, Foodborne bacteria detection, Magnetic separation.

Quantum Dots as Fluorescent Labels for Quantitative Detection of Salmonella Typhimurium in Chicken Carcass Wash Water

2005 ◽  
Vol 68 (6) ◽  
pp. 1241-1245 ◽  
Author(s):  
LIJU YANG ◽  
YANBIN LI
Keyword(s):  
Quantum Dots ◽  
Salmonella Typhimurium ◽  
Pathogenic Bacteria ◽  
Magnetic Beads ◽  
Cell Number ◽  
Wash Water ◽  
Quantitative Detection ◽  
Fluorescent Labels ◽  
Microbial Detection ◽  
Chicken Carcass

Fluorescent semiconductor quantum dots have recently emerged as a novel and promising class of fluorescent labels for biological detection. In this study, quantum dots were used as fluorescent labels in immunoassays for quantitative detection of foodborne pathogenic bacteria. Salmonella Typhimurium cells were separated from chicken carcass wash water using anti-Salmonella antibody coated magnetic beads and reacted to secondary biotin-labeled anti-Salmonella antibody. Quantum dots coated with streptavidin were added to react with biotin on the secondary antibody. Measurement of the intensity of fluorescence produced by quantum dots provided a quantitative method for microbial detection. A linear relationship between Salmonella Typhimurium cell number (log N) in the samples of chicken carcass wash water and the fluorescence intensity (FI) was found for the cell numbers ranging from 103 to 107 CFU/ml. The regression model can be expressed as FI = 198.6 Log N − 639.03 with R2 = 0.96. The detection limit of this method was 103 CFU/ml.

scholarly journals Development of an early warning system for loose automobile tires

2020 ◽  
Vol 103 (3) ◽  
pp. 003685042094088
Author(s):  
Huibo Wu ◽  
Fei Song ◽  
Kainan Wu ◽  
Cheng Chen ◽  
Xiaohua Wang
Keyword(s):  
Early Warning ◽  
Early Warning System ◽  
Traffic Accidents ◽  
Warning System ◽  
Working Environment ◽  
Vehicle Body ◽  
Economic Losses ◽  
Control Module ◽  
Alarm Signal ◽  
Monitoring Module

The looseness of tires or even falling off from cars will lead to serious traffic accidents. Once it occurs, it will bring casualties and huge economic losses to society, seriously affecting the traffic safety. To mitigate such possible safety concerns, an early loosening warning system is developed in this article. The system consists of the tire monitoring module and the working control module. The tire monitoring module is installed on the tire and is designed with no power supply. The control module is installed in the vehicle body. Signal transmission between the two modules is achieved through wireless radio frequency. In the driving, once the tire is loosened, the monitoring device will send out the alarm signal automatically and wirelessly. After the driver gets the alarm signal, he can immediately perform the emergency processing, parking, and inspection, which can avoid traffic accidents caused by it. This article introduces the detailed structure, working principle, and operation process of the system. This early warning system has simple structure, high reliability, and is easy to use. It can be used in the common working environment of automobiles. Meanwhile, it is also the foundation of intelligent connected vehicle.

scholarly journals Experimental infection of broiler chicks with Salmonella Typhimurium from pigeon (Columba livia)

2016 ◽  
Vol 37 (4) ◽  
pp. 1919
Author(s):  
Átilla Holanda de Albuquerque ◽  
Régis Siqueira de Castro Teixeira ◽  
Débora Nishi Machado ◽  
Elisângela De Souza Lopes ◽  
Ruben Horn Vasconcelos ◽  
...  
Keyword(s):  
Salmonella Typhimurium ◽  
Clinical Signs ◽  
Columba Livia ◽  
Poultry Feed ◽  
Economic Losses ◽  
Control Group ◽  
Broiler Chicks ◽  
Post Inoculation ◽  
Microbiological Analysis ◽  
Fecal Samples

Several cases of animal and human salmonellosis caused by the Salmonella serotype Typhimurium have been reported. In animals, subclinical infection favors pathogen dissemination through feces. In this context, the domestic pigeon (Columba livia) with an asymptomatic condition may play an important role in the transmission of salmonellosis, through the elimination of contaminated feces in commercial aviaries or in poultry feed facilities, causing economic losses to the poultry industry and presenting a risk to public health. This study aimed to evaluate the mortality, clinical signs and the presence of Salmonella Typhimurium in the feces and organs of chicks previously inoculated with bacteria isolated from a pigeon. One-day-old chicks were distributed in two experimental groups (G1 and G2) of 32 birds each, and a control group of six birds. Two inocula of 0.4 and 0.7 mL with 105 and 106 colony forming units were used in G1 and G2 birds, respectively. At 1, 4, 7 and 14 days post-inoculation (dpi) fecal samples were pooled from each cage and individual cloacal swabs were collected. At 14 dpi, all chicks were euthanized and samples were collected from the liver, spleen, lung, cecum and intestine for microbiological analysis. Mortality was only observed among G2 birds (6.25%). Most birds presented clinical signs of diarrhea at 4 dpi and no symptom as observed at 14 dpi. The results from cloacal swabs demonstrated bacterial elimination in 68.8% and 53.1% of G2 and G1 birds, respectively at 1 dpi. Additionally, fecal samples had elevated bacterial shedding in all four periods of observation , with a higher excretion at 4 dpi (62.5%) for both groups. Among G2 birds, 74.2% were positive for the pathogen in the intestine; G1 birds presented the lowest rate of lung infection (29%), and both groups had more than 50% positivity for liver and caeca. The results revealed that infected chicks with a Salmonella Typhimurium strains isolated from pigeons may host the pathogen in several organs, and simultaneously present diarrheic disorders with significant levels of bacterial excretion in feces.

Fabrication of an “ion-imprinting” dual-emission quantum dot nanohybrid for selective fluorescence turn-on and ratiometric detection of cadmium ions

The Analyst ◽  
2016 ◽  
Vol 141 (20) ◽  
pp. 5886-5892 ◽  
Author(s):  
Jing Wang ◽  
Chenxing Jiang ◽  
Xiaoqi Wang ◽  
Ligeng Wang ◽  
Aimin Chen ◽  
...  
Keyword(s):  
Quantum Dot ◽  
Fluorescence Detection ◽  
Ratiometric Fluorescence ◽  
Dual Emission ◽  
Cadmium Ions ◽  
Turn On ◽  
Ratiometric Detection ◽  
Ion Imprinting ◽  
Fluorescence Turn On

A new CdTe@SiO2@CdSe nanohybrid was demonstrated for the ratiometric fluorescence detection of Cd2+via the turn-on model and “ion-imprinting” technique.

scholarly journals A Rapid and Sensitive Europium Nanoparticle-Based Lateral Flow Immunoassay Combined with Recombinase Polymerase Amplification for Simultaneous Detection of Three Food-Borne Pathogens

2021 ◽  
Vol 18 (9) ◽  
pp. 4574
Author(s):  
Kai Chen ◽  
Biao Ma ◽  
Jiali Li ◽  
Erjing Chen ◽  
Ying Xu ◽  
...  
Keyword(s):  
Listeria Monocytogenes ◽  
Vibrio Parahaemolyticus ◽  
Pathogenic Bacteria ◽  
Simultaneous Detection ◽  
Lateral Flow ◽  
Recombinase Polymerase Amplification ◽  
Quantitative Detection ◽  
Bacterial Strains ◽  
Food Borne Pathogens ◽  
Food Borne

Food-borne pathogens have become an important public threat to human health. There are many kinds of pathogenic bacteria in food consumed daily. A rapid and sensitive testing method for multiple food-borne pathogens is essential. Europium nanoparticles (EuNPs) are used as fluorescent probes in lateral flow immunoassays (LFIAs) to improve sensitivity. Here, recombinase polymerase amplification (RPA) combined with fluorescent LFIA was established for the simultaneous and quantitative detection of Listeria monocytogenes, Vibrio parahaemolyticus, and Escherichia coliO157:H7. In this work, the entire experimental process could be completed in 20 min at 37 °C. The limits of detection (LODs) of EuNP-based LFIA–RPA were 9.0 colony-forming units (CFU)/mL for Listeria monocytogenes, 7.0 CFU/mL for Vibrio parahaemolyticus, and 4.0 CFU/mL for Escherichia coliO157:H7. No cross-reaction could be observed in 22 bacterial strains. The fluorescent LFIA–RPA assay exhibits high sensitivity and good specificity. Moreover, the average recovery of the three food-borne pathogens spiked in food samples was 90.9–114.2%. The experiments indicate the accuracy and reliability of the multiple fluorescent test strips. Our developed EuNP-based LFIA–RPA assay is a promising analytical tool for the rapid and simultaneous detection of multiple low concentrations of food-borne pathogens.

Electrochemical biosensor for detection of pathogenic bacteria based on dual signal amplification of Cu3(PO4)2-mediated click chemistry and DNAzyme

The Analyst ◽  
2021 ◽  
Author(s):  
Hongguo Wei ◽  
Jiayu Wan ◽  
Shengjun Bu ◽  
Wenguang Zhang ◽  
Ma Li ◽  
...  
Keyword(s):  
Click Chemistry ◽  
Magnetic Separation ◽  
Concanavalin A ◽  
Signal Amplification ◽  
Pathogenic Bacteria ◽  
Electrochemical Biosensor ◽  
Inorganic Hybrid ◽  
Highly Sensitive ◽  
Antibody Conjugates ◽  
Dual Signal Amplification

A novel electrochemical biosensor for detecting pathogenic bacteria was designed based on specific magnetic separation and highly sensitive click chemistry. Instead of enzyme-antibody conjugates, organic-inorganic hybrid nanoflowers (Concanavalin A (Con...

Ratiometric fluorescence detection of pathogenic bacteria based on dual-recognition nanoprobes with controllable G-quadruplex release

2021 ◽  
Author(s):  
Yizhong Shen ◽  
Tingting Wu ◽  
Huanhuan Chen ◽  
Yingwang Ye ◽  
Jing-Juan Xu
Keyword(s):  
Fluorescence Detection ◽  
Carbon Dots ◽  
Pathogenic Bacteria ◽  
Ratiometric Fluorescence ◽  
G Quadruplex ◽  
Promising Avenue

A dual-recognition carbon dots-based nanoprobe with controllable G-quadruplex release is developed for ratiometric fluorescence detection of pathogenic bacteria in a fast and precise way, which opens a promising avenue for...

Effect of Gamma Irradiation on the Survival of Pathogens in Kwamegi, a Traditional Korean Semidried Seafood

2003 ◽  
Vol 66 (11) ◽  
pp. 2093-2096 ◽  
Author(s):  
S. P. CHAWLA ◽  
D. H. KIM ◽  
C. JO ◽  
J. W. LEE ◽  
H. P. SONG ◽  
...  
Keyword(s):  
Low Temperature ◽  
Salmonella Typhimurium ◽  
Water Activity ◽  
Pathogenic Bacteria ◽  
Radiation Sensitivity ◽  
E Coli ◽  
Public Health Significance ◽  
Irradiation Treatment ◽  
Test Organisms ◽  
Health Significance

Kwamegi (semidried raw Pacific saury) is traditional seafood available in Korea. It has water activity in the range of 0.90 to 0.95. Spoilage and the growth of most pathogenic bacteria is retarded because of low water activity, low temperature, and packaging. However, it is contaminated with bacteria of public health significance and poses a hazard to the consumer because it is consumed raw without any cooking. The effectiveness of these hurdles in preventing the growth of Staphylococcus aureus, Bacillus cereus, Salmonella Typhimurium, and Escherichia coli and the efficacy of irradiation treatment in eliminating these bacteria from kwamegi using inoculated pack studies was examined. Radiation sensitivity of S. aureus, B. cereus, Salmonella Typhimurium, and E. coli in kwamegi was investigated. D10-values of these organisms in kwamegi were 590 ± 13.6, 640 ± 14.9, 560 ± 45.4, and 550 ± 8.6 Gy, respectively. The growth of all four test organisms inoculated into these foods during 4 weeks of storage at an ambient winter temperature (ranging from −5°C to +5°C) was recorded. All four pathogens (inoculated at 106 CFU/g) were eliminated by irradiation at 4 kGy. These studies unequivocally demonstrate that irradiation, with a combination of low water activity and low temperature, results in microbiologically safe kwamegi.

scholarly journals Lactic Acid Bacteria (Lactobacillus bulgaricus and Streptococcus thermophillus) in Yogurt Inhibit the Growth of Escherichia coli, Salmonella typhimurium, and Shigella sp. In Vitro

2021 ◽  
Vol 31 (4) ◽  
pp. 2
Author(s):  
IDSAP Peramiarti
Keyword(s):  
Escherichia Coli ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Salmonella Typhimurium ◽  
Pathogenic Bacteria ◽  
Test Method ◽  
P Value ◽  
E Coli ◽  
Significant Difference

Diarrhea is defecation with a frequency more often than usual (three times or more) a day (10 mL/kg/day) with a soft or liquid consistency, even in the form of water alone. Pathogenic bacteria, such as Escherichia coli, Salmonella typhimurium, and Shigella sp., play a role in many cases, to which antibiotics are prescribed as the first-line therapy. However, since antibiotic resistance cases are often found, preventive therapies are needed, such as consuming yogurt, which is produced through a fermentation process by lactic acid bacteria (LAB). This research aimed to determine the activity of lactic acid bacteria (Liactobacillus bulgaricus and Streptococcus thermophilus) in yogurt in inhibiting the growth of the pathogenic bacteria E. coli, S. typhimurium, and Shigella sp. The research applied in vitro with the liquid dilution test method and the true experimental design research method with post-test-only and control group design. The design was used to see the inhibitory effect of yogurt LAB on the growth of E. coli, S. typhimurium, and Shigell sp. to compare the effect of several different yogurt concentrations, namely 20%, 40%, 60%, and 80%. The results of the Least Significance Different analysis showed that there was a significant difference between yogurt with a concentration of 0% and that with various concentrations in inhibiting the growth of E. coli, S. typhimurium, and Shigella sp. with a p-value of &lt;0.05. Whereas, there was no significant difference in the various concentrations of yogurt in inhibiting the growth of the three kinds of bacteria with a p-value of &gt; 0.05.<p class="Default" align="center"> </p>

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