An international team of researchers has developed a micro- and nano-fluidic device stacked with magnetic beads that can rapidly isolate, retrieve and concentrate Escherichia coli (E. coli) bacteria from bodily fluids.
This image shows bacterial cells trapped in a 3D microbead matrix. Image credit: Wenrong He / Rochester Institute of Technology.
Inadequate water supplies and poor sanitation in low- and middle-income settings have elevated global concern for waterborne disease outbreaks.
Microorganisms such as E. coli can cause fecal contamination in recreational and drinking water and post a high risk of disease transmission.
Between 2003 and 2012, 390 outbreaks of E. coli infections in the United States were reported, which resulted in nearly 176,000 distinct illnesses.
While E. coli infection can be treated with common antibiotics, some strains of this bacterium have developed resistance to antibiotics.
“The rapid identification of drug-resistant bacteria allows health care providers to prescribe the right drugs, boosting the chances of survival,” said Dr. Ruo-Qian (Roger) Wang, a scientist in the Department of Civil and Environmental Engineering in the School of Engineering at Rutgers University-New Brunswick.
The nano-device developed by Dr. Wang and his colleagues isolates, retrieves and concentrates target bacteria from bodily fluids. It efficiently filters particles and bacteria, capturing about 86% of them.
It has magnetic beads of different sizes that are designed to trap, concentrate and retrieve E. coli. The small spaces between the beads are used to isolate bacteria in the device.
The inexpensive, transparent device is easy to fabricate and operate, making it ideal for detecting disease-causing organisms in laboratory and health care settings.
“We demonstrated that this system exhibits a very high bacterial capture efficiency and is capable of on-chip aggregation when dealing with lower concentration samples,” the researchers said.
“The bacteria are simply retrieved and concentrated in the designated buffer without altering the properties of bacteria.”
“We believe that our system can be used for a wide spectrum of medical and technological applications, including rapid diagnosis of drug-resistant bacteria in bodily fluids, drinking water monitoring, and food safety.”
The team’s paper was published in the journal ACS Applied Materials & Interfaces.
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Xinye Chen et al. 2020. Rapid Escherichia coli Trapping and Retrieval from Bodily Fluids via a Three-Dimensional Bead-Stacked Nanodevice. ACS Appl. Mater. Interfaces 12 (7): 7888-7896; doi: 10.1021/acsami.9b19311
