Deuterium Oxide (D2O) Determination in Water by Gas Chromatography–Mass Spectrometry Following Deuterium Exchange Headspace Extraction

Abstract

A reliable, simple and fast method for quantitative analysis of heavy water (D₂O) was developed using deuterium exchange headspace extraction–gas chromatography–mass spectrometry. The method is based on incubating the acetic anhydride with D₂O, CH₃COOD formation, headspace extraction of CH₃COOD (exchange of hydrogen for deuterium) and gas chromatography/mass spectrometry detection. The quantification was performed using single ion monitoring (m/z = 61). The calibration was linear (R² = 0.9998) in the concentration range of 1 × 10³–3 × 10⁵ mg/L). This method can measure D₂O concentrations in water from 0.27 g/L. It was applied for determination of D₂O in distilled water with accuracy RSD ≤ 6% and precision RSD ≤ 4%.