Mass spectrometry of volatile organic compounds ionised by laser plasma radiation

Vacuum UV radiation from laser-induced plasma is used to ionise volatile organic compounds (VOCs) released by living organisms during their mass spectrometric analysis at atmospheric pressure without sample preparation. It is shown that the probability of ionisation of organic compounds with different ionisation potentials and proton affinity at atmospheric pressure in the argon flow weakly depends on the compound parameters and can be 3.6 × 10^-5 – 1.4 × 10^-4. The VOC spectra of mouse and human biological fluids are obtained without sample preparation at room temperature of the sample. The possibility of using the proposed method for the diagnosis of pathological changes is demonstrated.