Photo ionisation-time of flight mass spectrometry (PI-TOFMS) has been established for the on-line analysis of complex gas mixtures. Therefore, it is a suitable tool for puff resolved chemical fingerprint screening of cigarette smoke. This capability can be used for quality control, to determine product variability during manufacturing, or even to identify counterfeit products.

In this study a deuterium lamp is used as the light source for single photon ionisation (SPI). The respective wavelengths/ionisation energy, i.e. the energy required to ionise the organic target compounds, is roughly in a range of 7 to 11 eV (177 nm to 112 nm). As most matrix gases such as oxygen, nitrogen, carbon dioxide and especially water vapour have higher ionisation energies of 12 eV and more, they will be suppressed efficiently by the applied technology as such.

Various commercially available cigarette brands and types are included in the study to prove the measurement principle. Multiple cigarettes of each brand/type were smoked as replicates applying the ISO 3308 smoking protocol. The organic compound fingerprint spectra of each single puff of the replicates was analysed and statistically evaluated. Samples with the same product properties are clustered accordingly, whilst product variability becomes statistically visible. Defective products as well as counterfeit cigarettes can be identified by the applied technology and statistical model, in case significant differences of the chemical fingerprint at puff level were observed.

By increasing the number of analysed products, the statistical model can be continuously improved, so that the quality of the classification of each new sample with respect to product variability, outliers or even counterfeit cigarettes is enhanced.