Glow discharge mass spectrometry method and device

A glow discharge mass spectrometry method comprising the following steps:

• a. placing a sample to be analyzed by glow discharge mass spectrometry in a cell of a glow discharge lamp;
• b. pumping a flow of gaseous species out of said cell;
• c. injecting a flow of plasma gas into said cell;
• d. applying an electric power to the electrodes of the glow discharge cell so as to light an ablation plasma at the surface of the sample to be analyzed;
• e. detecting ionized species of the plasma, analyzing said ionized species and measuring the species detected by glow discharge mass spectrometry;
• wherein said glow discharge mass spectrometry method further includes the following steps:
• f. heating a gas flow to a temperature T higher than the ambient temperature;
• g. injecting, into the glow discharge cell, said flow of gas heated to the temperature T for a duration D before the step d) of lighting the ablation plasma;
• and
• h. pumping a flow of gaseous species out of said cell for the duration D, so as to decontaminate the surface of the sample and/or the internal walls of the glow discharge cell before the lighting of the ablation plasma.

A glow discharge mass spectrometry device comprising:

• a glow discharge lamp, comprising a glow discharge cell, electrodes, and an electric supply source adapted to apply an electric power to the electrodes of the glow discharge cell, means for injecting a gas flow into the glow discharge cell, said injection means being connected to the glow discharge cell by fluid connection means and means for pumping a flow of gaseous species out of the glow discharge cell, said glow discharge lamp being adapted to form an ablation plasma at the surface of a sample to be analyzed in the presence of a flow of plasma gas in the glow discharge cell,
• a mass spectrometer comprising a detector adapted to detect ionized species of the plasma,
• wherein the glow discharge mass spectrometry device further includes:
• heating means adapted to heat a gas flow upstream from said glow discharge cell, the gas injection means being adapted to inject, into the glow discharge cell, a flow of gas heated to the temperature T for a duration D, and the pumping means are configured to pump a flow of gaseous species out of said cell for the duration D, so as to decontaminate the surface of the sample and/or the internal walls of the glow discharge cell before the lighting of the ablation plasma.