title: Interferences in in vivo neutron activation analysis.
abstract: Significant errors can occur in the measurement of the total amounts of N, P, Cl, Na, Ca and K in the human body by in vivo neutron activation analysis because of the presence of interfering activity in the gamma-ray energy spectrum. The interfering activity may be present for two reasons: firstly, patients may have received an administered radioisotope in an unrelated investigation; secondly, activation of elements not normally present in the body in large quantities may have occurred. The size and duration of these errors have been examined for two administered radioisotopes, 67Ga and 47Ca. The interferences due to activated iron and chromium from stainless steel prostheses have been examined, as well as those due to activated iodine and barium in radiographic contrast media. A description of the method by which we correct for those interferences is given. The effects of the shape of the standard spectra used in least squares analysis of the results have been examined.
mesh_terms: D000201:Activation Analysis; D001823:Body Composition; D003287:Contrast Media / Q000009:adverse effects; D006801:Humans; D009501:Neutron Activation Analysis; D009584:Nitrogen / Q000032:analysis; D011188:Potassium / Q000032:analysis; D019736:Prostheses and Implants / Q000009:adverse effects; D011868:Radioisotopes / Q000009:adverse effects; D013193:Stainless Steel
chemical_list: D003287:Contrast Media; D011868:Radioisotopes; D013193:Stainless Steel; D009584:Nitrogen; D011188:Potassium