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Updated: Aug 16, 2025
Quantifying Human Norovirus Virus-like Particles Binding to Commensal Bacteria Using Flow Cytometry
Published on: April 29, 2020
Evaluation of volume-based flow cytometry as a potential primary method for quantification of bacterial reference
Siyuan Liu1, Ziquan Wang2, Meng Wang2
1College of Food Science and Technology, Hebei Agricultural University, Baoding, 071001, China; Center for Advanced Measurement Science, National Institute of Metrology, Beijing, 100029, China; Hebei Key Laboratory of Analysis and Control for Zoonotic Pathogenic Microorganism, Hebei Agricultural University, Baoding, 071001, China.
Flow cytometry (FCM) offers a novel primary method for quantifying viable bacterial cells in reference materials. This method provides accurate, traceable results with lower uncertainty compared to traditional plate counts.
Area of Science:
- Microbiological Metrology
- Analytical Chemistry
- Flow Cytometry Applications
Background:
- Bacterial reference materials (RMs) are essential for microbiological detection.
- Traditional plate-based methods for bacterial enumeration in RMs have high uncertainty.
- There is a need for accurate and traceable quantification methods in microbiology.
Purpose of the Study:
- To describe a potential primary method for microbiological quantification using flow cytometry (FCM).
- To determine the number of viable Escherichia coli O157 (E. coli O157) cells in RMs.
- To assess the accuracy, traceability, and uncertainty of the FCM-based method.
Main Methods:
- Application of a flow cytometry (FCM)-based method for viable bacterial cell quantification.
- Use of Escherichia coli O157 (E. coli O157) as a model organism.
- Comparison of FCM results with the traditional plate-based method.
Main Results:
- The FCM method determined viable E. coli O157 cell counts as (5.48 ± 0.27) × 10^8 cells mL^-1.
- Results showed good agreement with the plate-based method (En = 0.47).
- The FCM method provided formal traceability to the SI with a relative expanded uncertainty of 4.93% (k=2), significantly lower than the plate-based method.
Conclusions:
- Flow cytometry (FCM) is a potential primary method for accurate and traceable quantification of viable bacterial cells.
- The FCM-based method offers a comprehensive uncertainty statement suitable for microbiological metrology.
- This study presents the first description of FCM as a primary method for bacterial RM characterization.
