title: Polymer-mediated extraction of the fluorescent compounds derived by Hantzsch reaction with dimedone for the sensitive determination of aliphatic aldehydes in air.
abstract: An extraction method based on the thermo-responsive precipitation of a water-soluble polymer, poly(N-isopropylacrylamide) [PNIPAAm], was applied to the concentration of dimedone (5,5-dimethylcycrohexane-1,3-dion) derivatives for the highly sensitive determination of aldehydes in air. Aliphatic aldehydes including formaldehyde, acetaldehyde, propanal, 1-butanal, 1-heptanal, and 1-hexanal in air were well solubilized into the aqueous solution of dimedone and ammonium acetate by mixing the solution and air sample in a polyvinyl fluoride bag. Fluorescent derivatives of aldehydes that had formed by the Hantzsch reaction with dimedone were concentrated by polymer-mediated extraction. The recoveries of the fluorescent compounds increased with increasing the carbon number of aldehyde and were more than 80% for the derivatives from aldehydes having more than three carbon atoms under the optimal conditions. Microgram per m3 (sub-ppb) levels of the aliphatic aldehydes, propanal, 1-butanal, 1-heptanal, and 1-hexanal, in ambient air were successfully determined by HPLC separation with fluorometric detection. The sampling volume and time required were only 1l and 20 s, respectively.
authors.affiliation: Department of Molecular Design and Engineering, Graduate School of Engineering, Nagoya University, Chikusa, Nagoya 464-8603, Japan. saitoh@numse.nagoya-u.ac.jp
authors.forename: Tohru
authors.initials: T
authors.lastname: Saitoh
authors.forename: Syuntaro
authors.initials: S
authors.lastname: Suzuki
authors.forename: Masataka
authors.initials: M
authors.lastname: Hiraide
mesh_terms: D000085:Acetates; D000388:Air / Q000032:analysis*; D000447:Aldehydes / Q000032:analysis* / Q000737:chemistry; D003512:Cyclohexanones / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D011108:Polymers / Q000737:chemistry*; D012995:Solubility; D013997:Time Factors
chemical_list: D000085:Acetates; D000447:Aldehydes; D003512:Cyclohexanones; D005456:Fluorescent Dyes; D011108:Polymers; C004774:dimedone; C018824:ammonium acetate