Patent ID: 8309917

Claim:
A method for mass spectrometry comprising heating a solid sample or a liquid sample to gasify an object to be measured contained in the solid sample or the liquid sample and to form a neutral gaseous molecule, and attaching a metal ion emitted from an emitter with an oxidized surface to the neutral gaseous molecule to ionize the neutral gaseous molecule, thereby performing mass analysis, wherein: the solid sample or the liquid sample is a sample that emits a reducing gas by heating, the heating for gasifying the object to be measured is performed at a temperature which is lower than the vaporization temperature of the solid sample or the liquid sample and is not less than the vaporization temperature of the object to be measured, and an oxidizing gas is supplied to the emitter by introducing the oxidizing gas into a chamber in which the emitter is located to suppress lowering of an emission ability of the emitter caused by the reducing gas emitted from the solid sample or the liquid sample.