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Concurrent Quantification of Cellular and Extracellular Components of Biofilms
Published on: December 10, 2013
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Interlaboratory study for the evaluation of three microtiter plate-based biofilm quantification methods
Jontana Allkja1,2, Frits van Charante3, Juliana Aizawa4
1LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal.
Scientific Reports
|July 3, 2021
Summary
This study compared biofilm quantification methods for Staphylococcus aureus. Plate counts demonstrated superior reproducibility and responsiveness in antimicrobial efficacy testing, making it the most reliable method.
Area of Science:
- Microbiology
- Biotechnology
- Infectious Diseases
Background:
- Microtiter plate methods are standard for biofilm assessment but often yield irreproducible results.
- Understanding the repeatability and reproducibility of these methods is crucial for reliable biofilm quantification.
Purpose of the Study:
- To evaluate the reproducibility and responsiveness of crystal violet, resazurin, and plate count methods for quantifying Staphylococcus aureus biofilm formation.
- To determine the most reliable method for antimicrobial efficacy testing using microtiter plates.
Main Methods:
- An interlaboratory study involving five laboratories was conducted.
- A standardized protocol for biofilm growth, challenge, and assessment was developed and followed.
- Three methods (crystal violet, resazurin, plate counts) were compared for quantifying Staphylococcus aureus biofilms.
Main Results:
- In control experiments, plate counts showed the highest reproducibility standard deviation (0.92) on the log10-scale.
- In treatment experiments evaluating sodium hypochlorite efficacy, plate counts exhibited the best responsiveness and reproducibility (Slope/SR = 1.02).
Conclusions:
- The microtiter plate serves as a versatile biofilm reactor with good repeatability and reproducibility.
- Plate counts are identified as the most reliable method for antimicrobial efficacy testing of Staphylococcus aureus biofilms due to superior responsiveness and reproducibility.
