Neutron Activation Analysis for Quantification

Neutron activation analysis (NAA) is one of the most important nuclear techniques for nanometallome quantification, as it can simultaneously measure more than 30 elements in a sample. The detection limits of NAA range from 10 to 10 gg In typically instrumental NAA, stable nuclides ( Z, the target nucleus) in the sample undergo neutron capture reactions in a flux of (incident) neutrons. The radioactive nuclides the compound nucleus) 

Ge et al. from our group, used NAA as a non-destructive standard method to quantify metallic impurities in carbon nanotubes (CNTs). Considerable amounts of iron, nickel, molybdenum, and chromium in the CNTs were found, which implies that these elements were dominantly used in the synthesis process. Small amounts of other impurity elements like manganese, cobalt, copper, zinc, arsenic, bromine, antimony, lanthanum, scandium, samarium, tungsten, and thorium are also found, which are presumed to have come from sources in chemical and physical manipulations used during the production process or in the precursors of the synthesis (Table 11.1). Although these commercial CNTs have been processed to reduce metal and amorphous carbon, even these as-purified samples still contain significant quantities of residual metals, which maybe contribute to the potential toxicological effects of CNTs. 

NAA is widely used as a non-destructive method for the determination of elements of geological, environmental, biological samples. Unlike other traditional multielement analytical techniques, NAA normally does not require any sample pretreatment. Possessing many merits of high efficiency, precision, and accuracy, NAA is also one of the primary analytical methods to certify the 

Note the contents of Mn and Cu were determined by ICP-MS. ND, lower than detection limit. Data are expressed as mean standard deviation of three independent determinations (pgg ). 

Element AP Half-life process ( y) (MeV) ratio (%) (eV) (Bqg- ) ENP) get nuclei) 

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