Abstract: To develop biomimetic fibroin/apatite composites with bone-like structure byalternate soaking method, the degummed natural fibroin fibers were pretreatedby soaking into CaCl₂:EtOH:H₂O (<>n(CaCl₂):<>n(EtOH):<>n(H₂O)=1:2:8) solution for given time and then soaked into calciumsolution and phosphate solution, respectively, to fabricate fibroin/apatite composites. The effects of pretreatment time andthe alternate soaking times on fibroin microstructure and fibroin/apatitecomposites were examined by SEM, FTIR, XRD and TGA techniques. The pretreatmentusing CaCl₂:EtOH:H₂O(<>n(CaCl₂):<>n(EtOH):<>n(H₂O)=1:2:8) solution makes fibroin fiber exhibit rougher surface and higher internalporosity, which is beneficial to interaction of calcium ion and residue groupssuch as -COOH, –OHand -CONH- from fibroin, and then improvethe deposition of apatite on fibroin fibers. The homogeneous apatites withoriented <>c-axis were formed on the pretreated fibroin fibers. Moreover,there are more than 30wt% apatites deposited on fibroin fibers after alternatesoaking for more than 3 times. The fibroin/apatite composite has potential tobe applied as bone repair materials.

Key words: natural fibroin fiber, apatite, biomineralization