Rapid and sensitive detection of Salmonella typhimurium based on the photothermal effect of magnetic nanomaterials

A strategy based on immune-magnetic nanomaterials was developed for the sensitive, rapid and simple detection of Salmonella typhimurium. High-efficiency capture, high-sensitivity thermal sensor detection and sterilization of Salmonella typhimurium can be simultaneously achieved using the combined magnetic and thermal properties of a magnetic nanomaterial. The temperature change caused by irradiating magnetic nanomaterials with a laser was used to establish a standard curve for the dependence of the temperature change on the number of Salmonella typhimurium bacteria. Under optimal conditions, the limit of detection was as low as 300 CFU mL−1. Salmonella typhimurium spiked in drinking water can be successfully detected in 1.5 h with a recovery between 96.2 ± 7.4% and 106.4 ± 5.6%.