NABI develops novel method to detect food pathogens

A detection platform with aptamer conjugation has been developed in this study

A team of researchers at DBT-National Agri-Food Biotechnology Institute (DBT-NABI), Mohali, has come up with a new method to detect food pathogens.

E. coli is the most common foodborne bacteria causing illnesses including diarrhea, fever, and death if left undiagnosed and untreated, which makes its detection most important. Traditional detection methods such as culture, PCR, or ELISA are time-consuming and require skilled manpower.

On the other hand, an aptamer called ssDNA is a stable, sensitive, and selective biomolecule used extensively for biodetection.

To provide naked eye detection, gold nanoparticles (AuNPs) were used by the researchers, and to increase the aptamer conjugation, AuNPs were covered with Graphene Oxide (GO). Thus, the overall sensitivity of the designed nanoprobe was also augmented. Therefore, exploiting the properties of gold nanoparticles and graphene oxide, a detection platform with aptamer conjugation has been developed in this study.

In the manifestation of E.coli cells, the visible color change was observed from red to blue within an hour of incubation. The limit of detection observed visually was 102 cells/mL with GO coating and 103 cells/mL without GO. The detection limit in real-time coconut water samples was also 102 cells/mL.This platform was found to be applicable in glass capillary which provides opportunities for making a point of care detection device.