High temperature reversed-phase HPLC using deuterium oxide as a mobile phase for the separation of model pharmaceuticals with multiple on-line spectroscopic analysis (UV, IR, 1H-NMR and MS)

The reversed-phase chromatography of a number of model pharmaceuticals using deuterium oxide (D2O) as the mobile phase at elevated temperatures, including superheated conditions (greater than 100 °C), is described. Following elution the analytes were characterised on-line via a combination of diode array UV, 1H-NMR, FT-IR spectroscopy and mass spectrometry. This combination of spectrometers enabled the on-flow collection of full UV, 1H-NMR, IR and mass spectra for a range of compounds in amounts ranging from 46 to 500 μg on-column. The advantages of the use of D2O alone as mobile phase for chromatography with multiple spectroscopic characterisation of analytes is discussed.