Detection of E. coli by improving biosensors

Researchers at Washington State University have developed a portable biosensor that makes it easier to detect harmful bacteria. The article was published in the magazine "Small".

Several foods have recently been recalled, and harmful pathogens are discovered when people start to get sick. Researchers have been working hard to develop better biosensors that can quickly and accurately detect cancer biomarkers in the blood and harmful bacteria in the environment. Even a small number of pathogens can pose serious health risks, but currently available sensors cannot detect these trace pathogens quickly and easily.

The researchers created a simple sensor that detects and amplifies the signal pathogen E. coli (E. coli) 0157:H7, which causes severe diarrhea and kidney damage.

The key to a good quality sensor is to maintain a large amount of enzyme activity when detecting the antigen of the sample. To solve this problem, the researchers developed a nanoscale particle that consists of organic and inorganic components that look like a very small flower. The particles are smaller than a single dust and consist of molecules. This nanoscale flower, the surface area of ​​the petals, is used to immobilize highly active enzymes to detect low levels of bacteria.

This nanoflower recognizes bacteria and amplifies the signal so that it can be detected with a simple handheld acidity meter or pH test strip.

“We wanted to use nanoflowers to create an easy-to-use handheld device that anyone can use anywhere,” Lin said. “It's as easy to use as a test strip or blood glucose meter for early pregnancy.”

Researchers applied for a patent for handheld device ideas and used to detect disease markers as well as other pathogens such as Salmonella.