Nanozyme Enhanced Colorimetric Immunoassay for Naked-Eye Detection of Salmonella Enteritidis

  • Nan Cheng
  • Chengzhou Zhu
  • Yinling Wang
  • Dan Du
  • Mei-Jun Zhu
  • Yunbo Luo
  • Wentao Xu
  • Yuehe Lin
Original Paper


Salmonella Enteritidis is a major public health threat of global proportions, while it is still a serious challenge to develop point-of-care detection assay. In this study, nanozymes (Fe-MOF nanoparticles) were successfully synthesized and applied as signal in a colorimetric immunoassay for naked-eye detection of Salmonella Enteritidis. After optimization, the proposed assay was able to detect Salmonella Enteritidis with a detection limit of 34 CFU/mL. The coefficients of variation (CV) of the test were less than 7.0% after 30 days storage at 4 °C. The estimated recoveries in milk samples of the colorimetric immunoassay range from 94.68 to 124%, which indicated the developed method is capable of detecting Salmonella Enteritidis in real samples. This method provides a potential platform for Salmonella detection with naked eyes, which has a significant application value for foodborne pathogen analysis at the point-of-care.


Salmonella Enteritidis Nanozyme Magnetic beads Colorimetric detection Immunoassay 



This work was supported by a WSU start up fund and China National Postdoctoral Program for Innovative Talents (BX20180364).


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Copyright information

© The Nonferrous Metals Society of China 2018

Authors and Affiliations

  1. 1.School of Mechanical and Materials EngineeringWashington State UniversityPullmanUSA
  2. 2.Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science and Nutritional EngineeringChina Agricultural UniversityBeijingPeople’s Republic of China
  3. 3.School of Food ScienceWashington State UniversityPullmanUSA

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