3.4. Bioinspired silicification on films
In order to study silica condensation on surfaces, the recombinant
spider silk protein and the chimeras were fabricated into films
using methods described previously [11]. In the films, shifts from
random coil to b-sheet were induced to prevent dissolution of films
by treating with water vapor at 50 C and 70 C, as well as 70%
methanol. Secondary structure conformation of the protein in the
films was investigated by FTIR. The 6mer or each of the chimeras
showed strong peaks in the amide I (1690–1600 cm1) and the
amide II (1575–1480 cm1) regions (Fig. S.1). For the untreated
films, the 6mer and the chimeras only showed peaks at 1649
cm1 in the amide I region, indicating the presence of random coils.
After self-assembly, a shift in the main peak from 1649 cm1 to
1624 cm1 was observed for the silk protein and each of the chimeras
indicating the formation of b-sheets.