Determining Inorganic and Organic Phosphorus.
Jaana Koistinen1, Mervi Sjöblom2, Kristian Spilling3,4
1Tvärminne Zoological Station, University of Helsinki, Hanko, Finland. jaana.koistinen@helsinki.fi.
Methods in Molecular Biology (Clifton, N.J.)
|April 30, 2026
Summary
This study introduces a colorimetric method to measure phosphorus (P) in microalgae. The technique quantifies orthophosphate (PO4), dissolved organic phosphorus (DOP), and particulate organic phosphorus (POP) for better nutrient analysis.
Area of Science:
- Environmental Science
- Biochemistry
- Analytical Chemistry
Background:
- Phosphorus is an essential macronutrient for microalgal growth.
- Orthophosphate (PO4) is the primary form of phosphorus uptake by microalgae.
- Accurate measurement of phosphorus forms is crucial for understanding aquatic ecosystems.
Purpose of the Study:
- To present a colorimetric method for determining orthophosphate (PO4) concentration.
- To describe a method for quantifying dissolved organic phosphorus (DOP).
- To outline a method for measuring particulate organic phosphorus (POP).
Main Methods:
- A colorimetric method based on total phosphorus (TP) measurements.
- Determination of PO4 concentration using spectrophotometry.
- Calculation of DOP and POP from TP measurements.
Main Results:
- The developed method allows for the quantification of PO4, DOP, and POP.
- The colorimetric approach provides a reliable way to assess phosphorus fractions.
- The methods are based on established principles of total phosphorus analysis.
Conclusions:
- The presented colorimetric methods enable comprehensive phosphorus speciation in microalgal samples.
- This technique aids in understanding phosphorus cycling and bioavailability in aquatic environments.
- The methods offer a practical approach for researchers studying microalgal nutrition and phosphorus dynamics.
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