Phosphorus determination in milk and bone samples by neutron activation analysis

The determination of phosphorus in milk and bone samples by both radiochemical and instrumental neutron activation analysis is described. The radiochemical method consists of thermal neutron irradiation of samples and standards, sample dissolution, phosphorus precipitation as ammonium phosphomolyb-date, use of zinc holdback carrier and counting of the phosphorus-32 ß-activity. The instrumental method involves thermal neutron irradiation of samples and standards, waiting for a decay time and ß-counting. The methods were applied to commercial samples and reference materials.