title: Naked-eye discrimination of methanol from ethanol using composite film of oxoporphyrinogen and layered double hydroxide.
abstract: Methanol is a highly toxic substance, but it is unfortunately very difficult to differentiate from other alcohols (especially ethanol) without performing chemical analyses. Here we report that a composite film prepared from oxoporphyrinogen (OxP) and a layered double hydroxide (LDH) undergoes a visible color change (from magenta to purple) when exposed to methanol, a change that does not occur upon exposure to ethanol. Interestingly, methanol-induced color variation of the OxP-LDH composite film is retained even after removal of methanol under reduced pressure, a condition that does not occur in the case of conventional solvatochromic dyes. The original state of the OxP-LDH composite film could be recovered by rinsing it with tetrahydrofuran (THF), enabling repeated usage of the composite film. The mechanism of color variation, based on solid-state (13)C-CP/MAS NMR and solution-state (13)C NMR studies, is proposed to be anion transfer from LDH to OxP triggered by methanol exposure.
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Ishihara
authors.forename: Nobuo
authors.initials: N
authors.lastname: Iyi
authors.forename: Jan
authors.initials: J
authors.lastname: Labuta
authors.forename: Kenzo
authors.initials: K
authors.lastname: Deguchi
authors.forename: Shinobu
authors.initials: S
authors.lastname: Ohki
authors.forename: Masataka
authors.initials: M
authors.lastname: Tansho
authors.forename: Tadashi
authors.initials: T
authors.lastname: Shimizu
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Yamauchi
authors.forename: Pathik
authors.initials: P
authors.lastname: Sahoo
authors.forename: Masanobu
authors.initials: M
authors.lastname: Naito
authors.forename: Hideki
authors.initials: H
authors.lastname: Abe
authors.forename: Jonathan P
authors.initials: JP
authors.lastname: Hill
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Ariga