Detection kit for listeria monocytogenes in food and application method

A technique for monocytogenes and Listeria, applied in the biological field, can solve the problems of inability to truly reflect the level of sample contamination, cumbersome and time-consuming operation, low sensitivity, etc., and achieve the effect of saving detection time, high sensitivity, and low background interference.

Inactive Publication Date: 2017-05-10
长沙市食品质量安全监督检测中心
View PDF9 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] There are many methods for detecting Listeria monocytogenes, such as real-time fluorescent polymerase chain reaction, fluorescent staining, immunological methods, etc. Although these methods have some advantages compared with traditional culture methods, there are still some problems that cannot be overcome. Disadvantages, such as cumbersome and time-consuming operation, low sensitivity, cannot truly reflect the contamination level of the sample, and "false positive" results, etc.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Detection kit for listeria monocytogenes in food and application method
  • Detection kit for listeria monocytogenes in food and application method
  • Detection kit for listeria monocytogenes in food and application method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0028] In this embodiment, the sensitivity test of the micro-gap array electrode kit with 96 holes is performed according to the following steps:

[0029] (1) Preparation of Listeria monocytogenes suspension: heat the bacterial solution in a water bath at 100°C for 15 minutes, and then perform serial dilutions to 10 8 cfu / mL, 10 7 cfu / mL, 10 6 cfu / mL, 10 5 cfu / mL, 10 4 Cfu / mL concentration of bacterial liquid;

[0030] (2) Drop the bacterial liquid into the chip hole embedded with the polyclonal antibody of Listeria monocytogenes, obtain the conductivity signal related to the concentration of Listeria monocytogenes from the electrode, and record the change value ,Such as figure 2 Shown.

[0031] The results showed that the higher the concentration of Listeria monocytogenes, the greater the conductance value, and the minimum detection limit can reach 10 5 cfu / mL.

Embodiment 2

[0033] In this embodiment, a specific test is performed on a 96-hole microgap array electrode kit, which is specifically performed according to the following steps:

[0034] Listeria monocytogenes, Enterobacter sakazakii, Salmonella, Pseudomonas aeruginosa, Escherichia coli O157:H7, Bacillus cereus, Vibrio parahaemolyticus (concentration of 10 7 cfu / mL) as the sample to be tested for cross-reaction research. The reaction results of the kit are as follows image 3 As shown, only Listeria monocytogenes is positive, and the rest are negative, indicating that the kit has good specificity.

Embodiment 3

[0036] The analysis of the actual sample using the 96-well microgap array electrode kit of this embodiment is carried out according to the following steps:

[0037] Take a positive sample of Listeria monocytogenes, and refer to the national standard GB 4789.30-2010 for sample processing, that is, take 25g of the test sample aseptically and add it to LB containing 225mL Listeria broth 1 In the homogenization cup of the enrichment liquid, homogenize with a homogenizer for 1 min to prepare a 1:10 sample homogenate, and incubate at 30℃±1℃ for 24h. Pipette 0.1mL of liquid and transfer to 10mL of Listeria broth LB 2 In the enrichment solution, incubate at 30°C±1°C for 18-24 hours, take 1 mL of the bacterial solution into a small test tube, heat it in a water bath at 100°C for 15 minutes, take it out, and cool to room temperature as the sample to be tested.

[0038] The sample to be tested is set up with positive and negative controls at the same time, and the test is performed. The reacti...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
concentrationaaaaaaaaaa
Login to view more

Abstract

The invention belongs to the field of biotechnology, and particularly relates to a detection kit for listeria monocytogenes in food and an application method. The detection kit comprises a fine pitch interdigital array electrode chip, wherein each chip hole of the fine pitch interdigital array electrode chip is coated with listeria monocytogenes polyclonal antibodies with the 100 [mu]L concentration being 5 [mu]g / mL. The detection kit based on fine pitch array electrodes is high in specificity and sensitivity, high in operation steps, can rapidly and accurately accomplish detection, is suitable for mass detection of samples, and is convenient for detecting the listeria monocytogenes in food samples.

Description

Technical field [0001] The invention belongs to the field of biotechnology, and specifically relates to a detection kit for Listeria monocytogenes in food and a method of use. Background technique [0002] Listeria monocytogenes is abbreviated as Listeria monocytogenes, which is a pathogen of zoonotic diseases. It can cause listeriosis in humans and animals, and the main manifestations after infection are sepsis, meningitis and abortion. Although the incidence of Listeria monocytogenes is low, the mortality rate is as high as 20%-30%. The pathogen is widespread in nature. Meat, eggs, poultry, seafood, dairy products and vegetables can all be contaminated. The bacteria can still grow and reproduce in an environment of 4°C. It is the main threat to human health in refrigerated food. One of the pathogenic bacteria. The country attaches great importance to the harm caused by Listeria monocytogenes contaminated food and has been listed as one of the national food safety strategic t...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): G01N33/535G01N33/569
CPCG01N33/535G01N33/56911
Inventor 周金沙杨丽霞邱华丽刘腊兰刘子音蒋成徐睿鑫夏立新
Owner 长沙市食品质量安全监督检测中心
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products