A new study introduces glycan-coated magnetic nanoparticles (gMNPs) as a faster, more efficient tool for detecting harmful pathogens in food.
Study: Rapid detection of foodborne pathogens using glycan-coated magnetic nanoparticles. Image Credit: monticello/Shutterstock.com
Published in Food Quality and Safety, the research responds to an urgent need for quicker pathogen detection methods, crucial for minimizing health risks and the economic impact of foodborne contamination.
Traditional techniques typically require lengthy microbial growth and enrichment steps to reach detectable bacterial levels, which can delay timely intervention. This study presents gMNPs as a promising solution, capable of rapidly isolating pathogens from food samples and streamlining the overall detection process to support faster public health responses.
Background
Foodborne illnesses remain a major global concern, responsible for an estimated 600 million cases and 420,000 deaths each year. These infections often result from pathogens such as Salmonella and E. coli, which can enter the food supply through contaminated produce or improper handling. Foods eaten raw—like fruits, salads, and ready-to-eat meals—are especially vulnerable.
Conventional detection methods rely on cultivating bacteria in nutrient-rich media, which can take several days. These delays make it harder to respond effectively and increase the risk of widespread contamination. Faster detection methods are therefore essential. This research aims to address that need without compromising on reliability or accuracy.
The Current Study
The study centers on the development and use of glycan-coated magnetic nanoparticles designed to selectively capture and concentrate Salmonella enterica serovar Enteritidis and E. coli from contaminated food. The nanoparticles were synthesized using a simple, scalable one-pot method, offering ease of production and potential for widespread application. Their performance was assessed by calculating a concentration factor (CF), which compares the viability of bacteria treated with gMNPs to untreated controls.
To demonstrate the method's versatility, researchers spiked various food items—including melons, cucumbers, raw chicken, and lettuce—with known amounts of the target pathogens. Following gMNP treatment, advanced imaging techniques such as transmission electron microscopy and confocal laser microscopy confirmed the nanoparticles’ successful binding to bacterial cells. These results held up across both buffer solutions and more complex food environments.
For detection, the team used real-time quantitative PCR (qPCR), enabling highly specific and rapid identification of pathogens without the need for lengthy pre-enrichment steps.
Results and Discussion
The findings showed that gMNPs effectively concentrated and extracted even low levels of E. coli and S. Enteritidis from complex food matrices. The reported concentration factors were strong—5.2±1.0 for E. coli and 3±1.3 for S. Enteritidis. Among the tested foods, melons yielded the highest CF for S. Enteritidis, followed by cucumbers, chicken, and lettuce.
Importantly, the method remained effective in the presence of natural microbiota, a common challenge in real-world food testing. The successful detection of pathogens was confirmed through both qPCR and selective plating, highlighting the technique’s robustness.
This gMNP-qPCR approach cut overall assay time to under four hours—significantly faster than traditional immunomagnetic separation methods, which often rely on costly and fragile recognition ligands. By eliminating the need for these ligands, gMNPs offer a more straightforward and cost-effective alternative, potentially making rapid testing more accessible across the food industry.
The study also points to future directions: refining the gMNPs for better binding across a wider range of pathogens and food types. This could support real-time monitoring in diverse food safety scenarios, helping to catch contamination before it spreads.
Conclusion
This research marks a significant step forward in food safety detection. The gMNP-qPCR system provides a rapid, reliable method for identifying bacterial contamination in food, addressing a critical need for faster pathogen detection. While further optimization is possible, the current results suggest this approach could become a valuable tool in routine food safety testing.
As global food systems grow increasingly complex, so does the challenge of ensuring safety at every stage. Continued advancements like this one are essential for staying ahead of emerging risks.
Journal Reference
Sharief S. A., Caliskan-Aydogan O., et al. (2025). Rapid detection of foodborne pathogens using glycan-coated magnetic nanoparticles. Food Quality and Safety 9, fyaf007, DOI: 10.1093/fqsafe/fyaf007, https://academic.oup.com/fqs/article/doi/10.1093/fqsafe/fyaf007/8023980?login=false