title: Control of calcium carbonate polymorphism and morphology through biomimetic mineralization by means of nanotechnology.
abstract: In vitro biomimetic mineralization by means of nanotechnology allows the formation of calcium carbonate polymorphs at low temperatures (<25 degrees C) under a CO(2) atmosphere of 500-1500 ppm. A two-dimensional zinc-ion ordered array (zinc array), which acts as an active-site mimic of carbonic anhydrase, has been prepared by immersing the self-organized monolayer of 3-(2-imidazolin-1-y)propyltriethosilane on mica (ImSi substrate) into aqueous zinc solution. The zinc array mounted on the ImSi substrate catalyzed the conversion from CO(2) to HCO(3) (-), and accelerated the formation of calcium carbonate. In situ X-ray diffraction data of the formed calcium carbonate on the poly(L-aspartate)-coated chitin substrate (pAsp substrate), with calcium ion-recognition sites, demonstrated that the interaction between the zinc array and pAsp substrates formed both vaterite and calcite at low temperature (15 degrees C) and mainly vaterite at 25 degrees C; this interaction also controlled the morphology of calcium carbonate formed on pAsp substrate.
authors.affiliation: Graduate School of Environmental Earth Science, Hokkaido University, Sapporo 060-0810, Japan. ichikawa@ees.hokudai.ac.jp
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Ichikawa
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Shimomura
authors.forename: Masanori
authors.initials: M
authors.lastname: Yamada
authors.forename: Naoki
authors.initials: N
authors.lastname: Ohkubo