title: Infrared study on deuteration of highly-crystalline chitin.
abstract: We report an infrared study of the deuteration of highly crystalline α- and β-chitin. With exposure to D2O vapor, the deuteration of α-chitin progressed on surface molecules, in contrast with β-chitin, which is partially deuterated on the inner part of the crystal. The intracrystalline deuteration occurred with high-temperature annealing in liquid D2O for α- and β-chitin. In α-chitin, the deuteration was similar between all the three functional groups. The ratio of deuterium/hydrogen increased with treatment temperature, and all the hydrogen in the functional groups was accessible above 200 °C. In β-chitin, the deuteration was more specific for each functional group. The deuteration of O3-H groups progressed rapidly, even below 100 °C, and, by contrast, that of O6-H and N-H progressed relatively slowly. These differences of deuteration between α- and β-chitin presumably arises from the particular ability of β-chitin to form a complex with water molecules.
authors.affiliation: Department of Biomaterials Science, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan.
authors.forename: Yu
authors.initials: Y
authors.lastname: Ogawa
authors.affiliation: Department of Biomaterials Science, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan; Department of Plant & Environmental New Resources, College of Life Sciences, Kyung Hee University, 1, Seocheon-dong, Giheung-ku, Yongin-si, Gyeonggi-do 446-701, South Korea.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kimura
authors.affiliation: Department of Biomaterials Science, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan.
authors.forename: Yukie
authors.initials: Y
authors.lastname: Saito
authors.affiliation: Department of Biomaterials Science, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan; Department of Plant & Environmental New Resources, College of Life Sciences, Kyung Hee University, 1, Seocheon-dong, Giheung-ku, Yongin-si, Gyeonggi-do 446-701, South Korea.
authors.forename: Masahisa
authors.initials: M
authors.lastname: Wada
mesh_terms: D000818:Animals; D002686:Chitin / Q000737:chemistry*; D003903:Deuterium / Q000737:chemistry*; D058087:Haptophyta; D013237:Stereoisomerism; D014961:X-Ray Diffraction / Q000379:methods
chemical_list: D002686:Chitin; D003903:Deuterium