Quaternized and boronic acid dual-functional CoAg nanozymes for label-free, stable, sensitive, and rapid quantitation...

Foodborne pathogenic bacteria lead to a significant increase in illnesses and fatalities annually. In the early stage of a pathogenic bacterial infection, the concentration of bacteria in food is lower than the detection limit of most technology which enhances the difficulty in diagnosis. It is a serious challenge for researchers to develop a rapid, sensitive, accurate, and stable pathogenic bacterial determination method without costly equipment and highly skilled operators.

It is clear that the bacterial total concentration in food increased obviously could be attributed to microbial contamination in food. Herein, quaternized and boronic acid dual-functional capped CoAg nanozymes, known as CoAg@HTCC-B, were developed and synthesized to exhibit strong and stable chemiluminescence (CL) emission to detect bacterial total concentrations. The CoAg@HTCC-B nanozymes are capable of accurately quantifying the total concentrations of a mixed bacterial solution (S. aureus and E. coli) over a broad detection range and with a low limit of detection (LOD). These nanozymes were utilized for the detection of E. coli or S. aureus in fresh chicken samples with LOD values of 2.08 colony-forming units per milliliter (CFU/mL) for E. coli and 1.71 CFU/mL for S. aureus.

This suggests that the CoAg@HTCC-B nanozymes have the potential for early-stage monitoring of microbial contamination in meat samples. The capability of CoAg@HTCC-B nanozymes in swiftly and accurately detecting known bacterial concentrations suggested their potential as a viable alternative to the traditional culture-based approach for quantitatively determining known bacterial concentrations in academic, research, or industrial settings.