화학공학소재연구정보센터
Langmuir, Vol.25, No.11, 6307-6311, 2009
Characterization of the Boundary Zone of a Cast Protein Drop: Fibroin beta-Sheet and Nanofibril Formation
We have studied a cast fibroin drop with grazing incidence small-angle X-ray scattering, imaging, and spectroscopy techniques. Optical microscopy shows that the dried drop forms a boundary zone. Grazing-incidence small-angle X-ray scattering performed with a synchrotron radiation microbeam in the boundary zone suggests the formation of nanometer-sized domains with one-dimensional paracrystalline order. Atomic force microscopy and scanning electron microscopy support a nanofibrillar morphology. MicroRaman spectroscopy shows the formation of beta-sheet secondary structure in the boundary zone, which is attributed to a shearing effect due to the retraction of the drop boundary upon evaporation.