Neptunium determination by dc glow discharge mass spectrometry (dc-GDMS) in Irish Sea sediment samples

Direct current glow discharge mass spectrometry (dc-GDMS) has applied for the direct analysis of 237Np in marine sediment samples from the Irish Sea. The secondary cathode technique was exploited to promote the sputtering of the sediment samples once compacted into a pellet. A certified marine sediment doped with a certified 237Np solution was used for obtaining matrix-matching samples for calibration purposes. Acquiring 100 points over an integration time of 300 ms a detection limit down to 80 pg g-1 was obtained. Results on 237Np were in agreement with those obtained by the determination of 233Pa by y-spectrometry.