FTIR (Fig. 1A) and XRD (Fig.
1B) analyses confirmed the formation of low
crystalline HA by in situ precipitation.
Compared to the conventional salt leaching
method, which normally results in
inhomogeneity of scaffold structure, salt fusion
created a controlled interconnected pore
structure (Fig. 1C). While cells on tissue
culture plates tended to be flat in shape 2 hours
after seeding, hMSCs on silk film containing
HA spread in a more spiky morphology with
multiple projections from the main cell body
(Fig. 2). Furthermore, with longer culture time,
cells on silk films containing HA developed
into a more slender morphology with narrow
projections (data not shown), a feature that might open potential for enhanced cell
migration. Cell proliferation on the composite
films was lower than that on TCP and pure silk
film, and decreased as the HA content
increased.