Immobilization of bone morphogenetic protein-2 to gelatin/avidin-modified hydroxyapatite composite scaffolds for bone regeneration. (April 2019)

• Record Type: Journal Article
• Authors: Cheng, Cheng-Hsin; Lai, Yi-Hui; Chen, Yi-Wen; Yao, Chun-Hsu; Chen, Kuo-Yu
• Is Part Of: Journal of biomaterials applications. Volume 33:Number 9(2019)
• Page Start: 1147
• Page End: 1156
• Publication Date: 2019-04
• Subjects: Bone morphogenetic protein-2 -- gelatin -- hydroxyapatite -- avidin -- bone-tissue regeneration; Biomedical engineering -- Periodicals; Biomedical materials -- Periodicals; 610.28
• DOI: 10.1177/0885328218820636
• Languages: English
• ISSNs: 0885-3282

Abstract

Bone scaffold surface characterization is important for improving cell adhesion, migration, and differentiation. In this study, bone morphogenetic protein-2 (BMP-2) was immobilized to the surface of the gelatin/hydroxyapatite composite using avidin–biotin binding system to produce a bone-tissue engineering scaffold. Firstly, hydroxyapatite particles reacted with hexamethylene diisocyanate and then the terminal group was converted into a primary amine group. Avidin was then immobilized on the surfaces of hydroxyapatite particles using N-ethyl-N′-(3-(dimethylamino)propyl) carbodiimide and N-hydroxysuccinimide as coupling agents. Gelatin was blended with avidin-modified hydroxyapatite and pure hydroxyapatite to obtain gelain/hydroxyapatite composite. The composite was then cross-linked with glutaraldehyde. Finally, biotin-conjugated BMP-2 was immobilized on the surface of the composite via avidin–biotin binding. In vitro study indicated that BMP-2-immobilized composite film had a higher ALP activity than that composite film without BMP-2. The composite scaffolds were then implanted into rabbit skulls to check bone-tissue regeneration. Ultrasound and micro-CT scans demonstrated that neovascularization and new bone formation in the BMP-2-immobilized composite scaffolds were higher than those in composite scaffolds without BMP-2. Histological evaluation result was similar to that of the micro-CT. Therefore, the surface immobilization of BMP-2 could effectively improve osteogenesis in the gelatin/hydroxyapatite composite scaffold.