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Quantifying Microorganisms at Low Concentrations Using Digital Holographic Microscopy (DHM)
Published on: November 1, 2017
A METHOD FOR THE QUANTITATIVE ESTIMATION OF BACTERIA IN SUSPENSIONS.
1Laboratories of The Rockefeller Institute for Medical Research, Princeton, N. J.
The Journal of General Physiology
|October 30, 2009
Summary
A new method accurately estimates bacterial cell concentration using packed cell column length in capillary tubes. This technique offers a rapid and precise approach for preparing bacterial suspensions with known cell densities.
Area of Science:
- Microbiology
- Biotechnology
- Analytical Chemistry
Background:
- Accurate bacterial cell concentration is crucial for various scientific and industrial applications.
- Traditional methods for cell enumeration can be time-consuming or require specialized equipment.
Purpose of the Study:
- To develop and validate a novel method for estimating bacterial cell concentration.
- To provide a rapid, accurate, and routineizable technique for preparing bacterial suspensions of defined cell densities.
Main Methods:
- Centrifugation of bacterial suspensions into fine-bore capillary tubes.
- Measurement of the packed cell column length.
- Validation of the method through direct cell counts.
Main Results:
- The method demonstrated high accuracy, with total errors of over 2% for dense suspensions and approximately 5% for light suspensions.
- The packed cell column length directly correlates with bacterial cell concentration.
Conclusions:
- The described capillary centrifugation method is a reliable and efficient tool for estimating bacterial cell concentration.
- This technique is suitable for routine laboratory work requiring precise bacterial suspensions.
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