3D-printed microchip quickly detects E. coli and salmonella in food

By Stephen Beech via SWNS

A new 3D-printed sensor is able to quickly detect potentially deadly food bugs such as E. coli and salmonella, according to a new study.

The microchip can reduce outbreaks of food poisoning by rapidly testing for multiple pathogens simultaneously, say scientists.

When food products are recalled because of some sort of contamination, it can trigger doubt in the minds of shoppers about the safety and reliability of what they eat and drink.

And, in some cases, a recall will come too late to stop people from falling ill.

In spite of the food industry’s efforts to fight pathogens, products are still contaminated and people still get sick.

Much of the problem stems from the fact that the tools available to screen for harmful pathogens are often not effective enough at protecting the public, say scientists.

Now Chinese researchers have developed a new method for detecting foodborne pathogens that they say is faster, cheaper, and more effective than existing technology.

The team from Guangdong University of Technology, and Pudong New District People’s Hospital hope, their technique can improve screening processes and keep contaminated food out of the hands of the public.

Study author Dr. Silu Feng said: “Detecting these pathogens is challenging, due to their diverse nature and the various environments in which they can thrive.

“Additionally, low concentrations of pathogens in large food samples, the presence of similar non-pathogenic organisms, and the complex nature of different food types make accurate and rapid detection difficult.”

He explained that detection methods do already exist, such as cell culture and DNA sequencing, but are “challenging” to employ on a large scale so not every batch of food can be thoroughly tested, and some contaminants inevitably slip through.

Dr. Feng said: “Overall, these methods face limitations such as lengthy result times, the need for specialized equipment and trained personnel, and challenges in detecting multiple pathogens simultaneously, highlighting the need for improved detection techniques.”

The Chinese research team, whose findings were published in the journal AIP Advances, decided to take a different approach, designing a microfluidic chip that uses light to detect multiple types of pathogens simultaneously.

Their chip is created using 3D printing, making it easy to fabricate in large amounts and modify to target specific pathogens.

Dr. Feng said the chip is split into four sections, each of which is tailored to detect a specific pathogen. If that pathogen is present in the sample, it will bind to a detection surface and change its optical properties.

The arrangement allowed the researchers to detect several common bacteria, such as E. coli, salmonella, listeria, and S. aureus, quickly and at very low concentrations.

Dr. Feng added: “This method can quickly and effectively detect multiple different pathogens, and the detection results are easy to interpret, significantly improving detection efficiency.”

The Chinese team plans to continue developing their device to make it even more applicable for food screening.