title: Glyoxal sample preparation for high-performance liquid chromatographic detection of 2,4-dinitro-phenylhydrazone derivative: Suppression of polymerization and mono-derivative formation by using methanol medium.
abstract: Some difficulties on a sampling of gaseous glyoxal using DNPH-silica cartridge were discussed, and an alternative sampling procedure was proposed. When glyoxal was sampled using the cartridge, it partially formed mono-hydrazone with various degrees, whereas it was quantitatively converted into its bis-hydrazone when sample gas was directly bubbled into a DNPH acidic solution. Additionally, glyoxal polymerized on the inner wall of the system during trapping to the silica cartridge. We found that the polymerization of glyoxal was effectively suppressed by dissolving glyoxal into methanol under reduced pressure; glyoxal in methanol readily reacted with DNPH in a hydrochloric acid solution and gave bis-hydrazone derivative, without any interference of methanol and any formation of mono-hydrazone derivative. When glyoxal was sampled by the proposed method, 102% of recovery was obtained, whereas it was reduced to 92.7% when the trapped glyoxal was dissolved into methanol under atmosphere.
authors.affiliation: Science Research center, Hosei University, 2-17-1 Fujimi, Chiyoda-ku, Tokyo 102-8160, Japan. knaka@hosei.ac.jp
authors.forename: Koichi
authors.initials: K
authors.lastname: Nakajima
authors.forename: Kyuji
authors.initials: K
authors.lastname: Ohta
authors.forename: Toufik A
authors.initials: TA
authors.lastname: Mostefaoui
authors.forename: Wen
authors.initials: W
authors.lastname: Chai
authors.forename: Takamitsu
authors.initials: T
authors.lastname: Utsukihara
authors.forename: C Akira
authors.initials: CA
authors.lastname: Horiuchi
authors.forename: Masahiko
authors.initials: M
authors.lastname: Murakami
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006037:Glyoxal / Q000737:chemistry*; D006835:Hydrazones / Q000032:analysis*; D000432:Methanol / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet
chemical_list: C001072:2,4-dinitrophenylhydrazone; D006835:Hydrazones; D011108:Polymers; D006037:Glyoxal; D000432:Methanol