基质辅助激光解吸电离飞行时间质谱鉴定沙门氏菌国标方法优化OA

The rapid identification of Salmonella,a significant foodborne pathogen,is of significant importance.To establish a new method for identifying Salmonella based on matrix-assisted laser desorption ionization time-of-flight mass spectrometry(MALDI-TOF MS),this study optimized culture medium type,incubation time,bacterial lysis methods,and instrumental parameters.The results showed that compared to the national standard method GB/T 33682-2025 General microorganism identification method with matrix-assisted laser desorption/ionization time of flight mass spectrometry,the recovery rate increased from 54.7%to 84.7%after replacing the culture medium with nutrient agar.Increasing the incubation time from 24 to 48 h increased the average identification score by 7.0%,from 2.203 to 2.355.Optimizing lysis methods elevated the average identification score by 19.0%,from 1.898 to 2.259.When the instrumental parameters were adjusted to 50%laser energy and a laser wavelength of 370 nm,the average identification score increased to 2.211.Compared to its original version specified in GB/T 33682-2025,the established MALDI-TOF/TOF MS method exhibited improved accuracy and reliability in Salmonella identification.