Recent Advances in Fluorescent Nanoprobes for Food Safety Detection.

Fluorescent nanoprobes show similar fluorescence properties to traditional organic dyes, but the addition of nanotechnology accurately controls the size, shape, chemical composition, and surface chemistry of the nanoprobes with unique characteristics and properties, such as bright luminescence, high photostability, and strong biocompatibility. For example, modifying aptamers or antibodies on a fluorescent nanoprobe provides high selectivity and specificity for different objects to be tested. Fluorescence intensity, life, and other parameters of targets can be changed by different sensing mechanisms based on the unique structural and optical characteristics of fluorescent nanoprobes. What's more, the detection of fluorescent nanoprobes is cost-saving, simple, and offers great advantages in rapid food detection. Sensing mechanisms of fluorescent nanoprobes were introduced in this paper, focusing on the application progress in pesticide residues, veterinary drug residues, heavy metals, microbes, mycotoxins, and other substances in food safety detection in recent years. A brief outlook for future development was provided as well.

Rapid detection of trace Salmonella in milk using an effective pretreatment combined with droplet digital polymerase chain reaction.

Salmonella is one of the most dangerous food-borne pathogens around the world to cause a threat to humans and it is urgent to develop the rapid detection method of trace Salmonella in food. Although many advanced techniques have been widely applied to shorten the detection time, the pretreatment method usually used of traditional enrichment and plate culturing to separate Salmonella are complicated and time-consuming. Herein, we developed an effective pretreatment method based on in situ enrichment culture with an immunomagnetic separation step, combined with droplet digital polymerase chain reaction (ddPCR) technology to achieve rapid detection of trace Salmonella in milk, which allowed detecting as low as 10-1 CFU/mL level of Salmonella. It took 8 h to perform the entire testing process from pretreatment to ddPCR detection and analysis. The pretreatment method could be a suitable platform integrating with many detection techniques for the rapid detection of trace Salmonella.