Polarized neutrons observed nanometer-thick crystalline ice plates in frozen glucose solution

Kumada, Takayuki   ; Nakagawa, Hiroshi   ; Miura, Daisuke; Sekine, Yurina   ; Motokawa, Ryuhei   ; Hiroi, Kosuke  ; Inamura, Yasuhiro  ; Oku, Takayuki   ; Oishi, Kazuki*; Morikawa, Toshiaki*; Kawamura, Yukihiko*; Kawai, Kiyoshi*

The structure of nano-ice crystals in rapidly frozen glucose solution was elucidated by using spin-contrast-variation small-angle neutron scattering, which distinguishes the nano-ice crystal signal from the frozen amorphous solution signal by the polarization-dependent neutron scattering. The analysis revealed that the nano-ice crystals form a planar structure with a diameter exceeding tens of nanometers and a thickness of 1 nm, which is close to the critical nucleation size. This result suggests that the glucose molecules are preferentially bound to a specific face of nano-ice crystals, and then block the crystal growth perpendicular to that face.