IRMS: LGR DLT-100 Liquid Water Isotope Analyzer


The DLT-100 Liquid-Water Isotope Analyzer measures hydrogen and oxygen isotope ratios (δ18 O and δ2 H) in liquid water samples.

Sample isotope ratios are standardized using a range of reference waters which have been calibrated against IAEA reference waters (VSMOW2, GISP2, and SLAP2). Precision for water samples at natural abundance is typically ≤0.3 ‰ for δ18 O and ≤2.0 ‰ for δ2 H. Final δ18 O and δ2 H values are reported relative to VSMOW.

This instrument uses a laser-based absorption technique involving off-axis integrated-cavity laser spectroscopy. It measures laser absorption within a cavity with high-reflectivity mirrors to generate path lengths of several kilometers resulting in clear separation of laser absorption lines of different water molecules. For more information on the theory of instrument operation, see Los Gatos Research website:

Turbid water samples or water samples containing precipitate must be filtered prior to analysis. 0.9 mL of 0.2um filtered sample is required. 10 replicates are sequentially measured for each sample using PAL autosampler. The first 5 measurements are discarded to eliminate memory effects, and the average of the last 5 measurements is used for isotope ratio calculations.

  • Laser-based absorption involving off-axis integrated-cavity laser spectroscopy
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non-profit rate

Instrument set up fee Level 1     LGR DLT-100     $25 $35 Rates charged per user, per analytical session
Sample charge Level 2     LGR DLT-100     $6.50 $25 Rates charged per user, per analytical session