Validation of a method for analysis of soluble phosphorus by use of alkaline extraction and spectrophotometric determination

Summary

The aim of this project is to validate Nofima BioLab’s method for analysis of soluble phosphorus. The definition of soluble phosphorus in this context is phosphorus that is not bound in bone material. Validating a method means investigating and establishing the method’s quality parameters. The tested method parameters will include recovery, bias, precision, ruggedness, limit of detection, limit of quantification, and uncertainty. The recovery test/spiking showed how important it is to have knowledge about the properties of the phosphate salts, especially the solubility. The repeatability of the method is similar to the repeatability of the well-established method for analysis of total phosphorus (ISO 6491). The combined measurement uncertainty of the method is low where the largest uncertainty contribution comes from diluting the sample.