A low- and middle-income country like India require a rapid and affordable test to check the contamination in food products like fruit juices. Aptamer-based assay meets the criteria and can cater to the vast needs of common masses. The Aptamer-NanoZyme – based assay is simple to handle and detects E. coli contamination in fruit juice with 5 minutes without any requirement of sophisticated instruments. It costs roughly two dollars.
The assay is based on the peroxidase-like activity (enzyme activity) of gold nanoparticles (NanoZyme) and the high affinity and selectivity of an aptamer. When the aptamer binds with pathogenic E. coli, it produces a colorful product that can be viewed by the naked eye, making the test result easy to read. Aptamer based E. coli detection approach can serve as a valuable tool for the food industry to ensure bacterial contamination absent in packaged foodstuff.
Pathogenic strains of E. coli have emerged as a threat to public health as it contaminates both food and water. Therefore, its early detection is of fundamental importance to avoid any severe medical situations associated with its infection. The conventional methods of E. coli detection are time-consuming and require technical expertise. Advance medical diagnostics based on the principle of Enzyme-Linked Immunosorbent Assay (ELISA) and Polymerase Chain Reaction (PCR), are accurate and relatively quick. However, they are expensive and require well-trained human resources and complex instrumentation facilities.
In 2015, the World Health Organization (WHO) reported that 1 in 10 people fall ill due to food contamination, which results in the death of about 420,000 people every year. According to another report published in 2016, diarrhea caused by water contamination leads to 829,000 deaths globally.
The work was published in the journal Sensing and Bio-sensing Research.