PNNL

Abstract

A variety of metal beta-diketonate polymers were assessed for gas-phase selective retention of nitro aromatic, nitrate ester, and peroxide explosives. La(dihed) showed 13-42 times the retention for the nitro aromatics compared to a control column (identical column but lacking the 5% loading of the metal beta-diketonate polymer). Nitrate esters, the peroxide explosive TATP, and the taggant DMDNB were too strongly retained to elute from the La(dihed) column; however, these compounds could be eluted from the less retentive Cu(dihed) or Zn(dihed) columns. A Kovats index of 2124 for TNT the on the La(dihed) column compared to 1662 on the control illustrates the excellent discrimination against non-polar hydrocarbons, the principal matrix interference expected in air samples. A proof-of-principle experiment demonstrated analysis of an extrapolated 47 part-per trillion(v/v) of TNT in an air extract concentrate.