Extraction of volatile PAHs from air by use of solid cyclodextrin

An approach for extraction of polycyclic aromatic hydrocarbons (PAHs) from air using solid cyclodextrin is presented. A comparison study in which beta-cyclodextrin is replaced by alpha-cyclodextrin provides evidence that beta-cyclodextrin extracts vapor phase PAHs by formation of inclusion complexes rather than by association or adsorption interactions. Thus, solid cyclodextrin complexes with vapor phase PAHs and thereby reduces their volatilities. The gas-solid interaction of the PAHs with beta-cyclodextrin and the effect of beta-cyclodextrin on the volatilities of these compounds are discussed. Fluorescence and absorbance spectroscopies are used to examine the variables that affect the formation of the PAH complexes with the solid cyclodextrin. The use of this system for improved ambient air sampling is proposed.