Simultaneous detection of Staphylococcus aureus and Salmonella typhimurium using multicolor time-resolved fluorescence nanoparticles as labels.
Foodborne illnesses caused by Staphylococcus aureus and Salmonella typhimurium are common public health issues worldwide, affecting both developing and developed countries. In this study, aptamers labeled with multicolor lanthanide-doped time-resolved fluorescence (TRFL) nanoparticles were used as signal probes, and immobilized by Fe3O4magnetic nanoparticles were used as the capture probes. The signal probes were bonded onto the captured bacteria by the recognition of aptamer to form the sandwich-type complex. Under the optimal conditions, TRFL intensity at 544nm was used to quantify S. typhimurium (y=10,213×-12,208.92, R2=0.9922) and TRFL intensity at 615nm for S. aureus (y=4803.20×-1933.87, R2=0.9982) in the range of 102-105CFU/ml. Due to the magnetic separation and concentration of Fe3O4nanoparticles, detection limits of the developed method were found to be 15, 20CFU/ml for S. typhimurium and S. aureus, respectively. The application of this bioassay in milk was also investigated, and results were consistent with those of plate-counting method. Therefore, this simple and rapid method owns a great potential in the application for the multiplex analysis in food safety.
State Key Laboratory of Food Science and Technology, Synergetic Innovation Center of Food Safety and Nutrition, School of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
Xiaole
X
Wang
School of Food and Bioengineering, Xihua University, Chengdu 610039, China.
Yukun
Y
Huang
State Key Laboratory of Food Science and Technology, Synergetic Innovation Center of Food Safety and Nutrition, School of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
Shijia
S
Wu
State Key Laboratory of Food Science and Technology, Synergetic Innovation Center of Food Safety and Nutrition, School of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
Nuo
N
Duan
State Key Lab Meat Processing & Quality Control, Yurun Group, Nanjing 210041, China.
Baocai
B
Xu
State Key Laboratory of Food Science and Technology, Synergetic Innovation Center of Food Safety and Nutrition, School of Food Science and Technology, Jiangnan University, Wuxi 214122, China. Electronic address: wangzp1974@163.com.
Zhouping
Z
Wang
D000588:Amines / Q000737:chemistry; D000818:Animals; D052157:Aptamers, Nucleotide; D015169:Colony Count, Microbial; D005290:Ferric Compounds / Q000737:chemistry; D005453:Fluorescence; D019649:Food Industry; D005516:Food Microbiology; D059022:Food Safety; D005517:Foodborne Diseases; D008280:Magnetics; D053768:Metal Nanoparticles / Q000737:chemistry; D008856:Microscopy, Fluorescence / Q000379:methods*; D008892:Milk / Q000382:microbiology; D012486:Salmonella typhimurium / Q000302:isolation & purification*; D013203:Staphylococcal Infections; D013211:Staphylococcus aureus / Q000302:isolation & purification*
D000588:Amines; D052157:Aptamers, Nucleotide; D005290:Ferric Compounds; C000499:ferric oxide
Aptamer; Foodborne pathogen; Simultaneous detection; Time-resolved fluorescence nanoparticles