Electrospun fibrous web of collagen–apatite precipitated nanocomposite for bone regeneration

Electrospinning is regarded as a facile tool to generate biomaterials into a nanofibrous structure. Herein a nanofibrous web constituted of collagen and hydroxyapatite (HA) was produced from their co-precipitated nanocomposite solution by using the electrospinning method. The co-precipitated sol was freeze-dried and the dried product was dissolved in an organic solvent for the electrospinning. The electrospun web showed a well-developed nanofibrous structure with HA contents of up to 20 wt%. The internal structure of the collagen–20 wt%HA nanofiber revealed highly elongated apatite nanocrystallines precipitated within the collagen matrix. However, above the HA content of 30 wt% the nanofibrous structure could not be preserved due to the formation of beads. The MC3T3-E1 osteoblastic cells were shown to adhere and grow actively on the collagen–HA nanofibrous web. The alkaline phosphatase (ALP) activity expressed by the cells on the collagen–20 wt%HA nanofiber was lower at day 7, but was higher at day 14 than that on the pure collagen nanofiber. Based on the study, the newly-developed collagen–HA nanofiber may be useful as a cell supporting substrate in bone regeneration area.