(562g) Measurement of Hansen Solubility Parameter on Pollen Particle Surface and Application to Pollen Removal in Air

Pollen from various vegetation such as cedar and cypress can negatively affect human health. For example, it shows allergic reactions to the human, such as rhinitis and fever. Allergies caused by pollen are spread all over the world and especially in Japan, one in four people has developed allergic symptoms. So, various attempts have been made to mitigate the effects of pollen on human health. Studies of the effects of removing pollen from air using air purifiers, pollen filters, and nasal filters have also been performed. The possibility of preventing exposure to pollen by repelling the pollen using electrostatic barriers has also been studied. Studies of methods of alleviating allergic symptoms using antihistamines, immunotherapy, and other methods have also been performed. I gave most attention to remove pollen from air by efficiently collecting the pollen with spray mist. In order to efficiently collect pollen, it is necessary to design a solvent having high affinity with pollen. To achieve that requires, we have to understand the physical properties of the pollen surfaces. So, I focused on Hansen Solubility Parameter (HSP), which is used for evaluating the physical properties of the fine particle surface.

HSP is physical property value of each substances. HSP is based on the idea that “two substances having similar interactions between molecules are high affinity". And HSP is consisted of 3 components: dispersion forces term, polar forces term and hydrogen-bonding forces term. The dispersion force term is the general van der Waals interactions between just about everything. Polar force term is the familiar “positive attracts negative” electrical attractions arising from dipole moments. hydrogen-bonding forces term is due to hydrogen bonding. HSP is measured experimentally by evaluating the affinity with organic solvents and using Hansen solbility sphere method. Since HSP is possible to grasp the surface physical properties of the material quantitatively, it has been used for many fields, such as petroum, pharmacy and food.

In this experiment, I measured HSPs for pollen particle, cedar and cypress which are major allelgen in Japan, using Hansen solbility sphere method. For HSP measurement on a fine particle surface, the affinity evaluation by the sedimentation method and dynamic light scattering method (DLS) are commonly used. However, HSP measurement of low-density and non-spherical particles like pollen by the above-mentioned measurement methods is difficult. So, I measured HSPs of each pollen by the capillary penetration method which is I developped.

Finally, considering these HSPs, I designed mixed solvents highly compatible with pollen and presented guidelines for future research and development.