RAPID ONLINE CHROMATOGRAPHIC DETERMINATION OF TRACE-LEVEL MUNITIONS IN AQUEOUS SAMPLES

An on-line trace enrichment system is described that combines a diviny lbenzene-vinylpyrrolidone co-polymer precolumn with a reversed-phase C -18 HPLC analytical column. This arrangement allows quantitative preco ncentration of munitions on the resin sorbent, followed by complete tr ansfer of analyte to the analytical column for separation, followed by UV absorbance detection at 254 nm. Detection limits were approximatel y 0.10 ng/ml for TNT and RDX when 10 ml of sample was analyzed. The fe asibility of increasing sample volume (up to 50 ml) to obtain detectio n limits down to 20 pg/ml was also demonstrated for TNT. Analyses of a quifer samples collected in the vicinity of a military installation ar e presented to show system utility.