ATP Bioluminescence-based Weak Signal Detection Technology

Microbial contamination of food is a serious threat to the health and safety of people. It isvery important to enhance the level of food safety inspection technology. Traditional detection ofbacterial and microbial amounts method is nutrient agar plate count method (PCA). Howeverthere are several limitations in PCA method. It has to be cultivated under37℃for48hours, andthe operation is very complex. It can’t be detected rapidly.The result of the rapid detectionmethod can be simply obtained in a few minutes, which is suitable for real-time monitoring ofmicrobial contamination. And it satisfied the need of food processing industry.This paper introduces a method based on ATP (Adenosine triphosphate) bioluminescenttechnique for rapid detection of bacteria and microbial quantity. This method can detect thequantity of bacteria and microbial food quickly and efficiently. It can be operated simply andrapidly with a high sensitivity. ATP is a kind of high-energy phosphate compounds, and all livingcells contain ATP molecules. For example, the content of ATP extracted from Escherichia colireaches6×10-9—14×10-9mg in dry mycelium per mg. ATP can release the fluorescence whenadded some certain chemical reagent.There’s a linear correlation between the microbe quantity contained in the sample and thecontent of ATP value, and it can be expressed by an equation. So we can get the quantity of themicroorganisms by detecting the luminous intensity.The measured number of microorganisms contained in the sample and the content of ATPvalue with a certain linear relationship. Meanwhile, the value of ATP with the values offluorescence released by ATP has a certain function relation. Therefore, detection the luminousintensity of ATP can indirectly obtain the number of microorganisms in the samples to bedetected. This thesis expounds in detail each part of the design ideas and the detection systemcomponent. The signal processing unit is the core module of the whole detection system; itdetermines the accuracy of the measurement system. Reagent is added to the detected samples in the ATP glimmer make ATP to shimmer. Using the high sensitivity photomultiplier tube (PMT)to collect light signal. Amplifier the signal, and then convert it to digital signal, according to thelight value can launch the number of microorganisms to determine the food hygiene situation.ATP bioluminescence assay received extensive attention in recent years because of itssimple operation and high sensitivity in the detection of food microorganism real simple. But thecurrent ATP detecting technology products still have high demands on technology, how todistinguish the species of bacteria also has difficulty. With the development of science andtechnology, ATP bioluminescence technology is expected to be an ideal microbial detectionmethod and get more extensive application by continuous improvement and perfection.