Fixation of tobacco smoke aerosols for size distribution studies

Abstract

Determination of the particle size distribution in the particulate phase of tobacco smoke is difficult due to the liquid nature and high coagulation rate of this aerosol. The use of methyl 2-cyanoacrylate vapor to “fix” smoke particles permits the study of the size distribution of the smoke particles as they exit from the cigarette. Vapors of methyl 2-cyanoacrylate monomer polymerize due to water in the smoke particles. This fixes the shape of the particles that may be collected on a carbon film supported by an electron microscope grid. Electron micrographs of a sufficient number of particles are taken to yield statistically significant data for a histogram. Differences in smoke particle size distribution have been observed for different cigarette filters. Particle size distributions of the methyl 2-cyanoacrylate fixed smoke were found to be essentially the same as those obtained from smoke frozen at liquid N 2 temperature and replicated with a freeze-etch equipment. Other types of liquid aerosols have been evaluated by this technique, and the same degree of success has been obtained as with tobacco smoke aerosols.