High-Throughput Measurement and Classification of Organic P in Environmental Samples

Many types of organic phosphorus (P) molecules exist in environmental samples(1). Traditional P measurements do not detect these organic P compounds since they do not react with colorimetric reagents(2,3). Enzymatic hydrolysis (EH) is an emerging method for accurately characterizing organic P forms in environmental samples(4,5). This method is only trumped in accuracy by Phosphorus-31 Nuclear Magnetic Resonance Spectroscopy ((31)P-NMR) -a method that is expensive and requires specialized technical training(6). We have adapted an enzymatic hydrolysis method capable of measuring three classes of phosphorus (monoester P, diester P and inorganic P) to a microplate reader system(7). This method provides researchers with a fast, accurate, affordable and user-friendly means to measure P species in soils, sediments, manures and, if concentrated, aquatic samples. This is the only high-throughput method for measuring the forms and enzyme-lability of organic P that can be performed in a standard laboratory. The resulting data provides insight to scientists studying system nutrient content and eutrophication potential.