Figure 2. Conformational changes in ß-TCP/collagen (A) and hydroxyapatite/collagen (B) composites 30 sec, and 10, 20, and 30 min after being mixed. N-H stretching at 3310 cm^–1 for amide A, C-H stretching at 3063 cm^–1 for amide B, C=O stretching at 1600–1700 cm^–1 for the amide I, N-H deformation at 1500–1550 cm^–1 for the amide II, and N-H deformation at 1200–1300 cm^–1 for the amide III band were detected in the ß-TCP/collagen composite. An isolated OH group around 3600 cm^–1was detected only in the ß-TCP/collagen, while amides A and I increased at the beginning of analysis. All data were confirmed with 6 different samples, respectively, for each composite.