• B. mori silk fibroin;
  • biomineralization;
  • biopolymers;
  • hydroxyapatite crystals;
  • interfaces;
  • nucleation;
  • self-assembly


Bombyx mori silk fibroin (SF) is known to be capable of facilitating nucleation of the hydroxyapatite crystals (HAps). To find out how SF mediates the nucleation of HAps, self-assembly of SF in 1.5 simulated body fluid (SBF) was observed in this study through design of a co-solution of SF and 1.5-times SBF (SF/1.5 SBF). After the co-solution of SF/1.5 SBF was incubated at 37.2 °C up to 7 days, SEM, X-ray, and Fourier transform infrared (FTIR) observations indicated that nucleation of HAps was increased. In addition, the structure of SF was transited from random coil into β-sheet indicated by FTIR spectra. The β-sheet assembly of SF in 1.5 SBF was also supported by CD spectra. Atomic force microscopy provided detailed progress of the self-assembly that SF incubated in 1.5 SBF was self-assembled in the form from dot, through rod to final net. Therefore, this study suggested that nucleation of HAps of SF was controlled by its molecular self-assembly. © 2013 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2013