TY - JOUR

T1 - Amino-modified silica surfaces efficiently immobilize bone morphogenetic protein 2 (BMP2) for medical purposes

AU - Ehlert, Nina

AU - Hoffmann, Andrea

AU - Luessenhop, Tammo

AU - Gross, Gerhard

AU - Mueller, Peter P.

AU - Stieve, Martin

AU - Lenarz, Thomas

AU - Behrens, Peter

N1 - Funding information: This work was supported by the DFG within the Collaborative Research Program SFB 599 “Sustainable Bioresorbable and Permanent Implants Based on Metallic and Ceramic Materials”. We thank our colleagues in work packages D1 (“Functionalized Middle Ear Prostheses”) and D7 (“Implant surfaces”) for valuable discussions.

PY - 2010/12/25

Y1 - 2010/12/25

N2 - Due to its ability to induce de novo bone formation the differentiation factor bone morphogenetic protein 2 (BMP2) is often used to enhance the integration of bone implants. With the aim of reducing possible high dose side-effects and to lower the costs, in order to produce affordable implants, we developed a simple and fast method for the immobilization of BMP2 on silica-based surfaces using silane linkers which carry amino or epoxy functions. We put an especial emphasis on the influence of the nanoscale surface topography of the silica layer. Therefore, we chose glass (for control experiments) and Bioverit® II (as a typical implant base material) as support materials and coated these substrates with unstructured or nanoporous amorphous silica layers for comparison. Immobilized BMP2 was quantified by two different methods: by ELISA and by a cell-based assay for active BMP2. These tests probe for immunologically and biologically active BMP2, respectively. The results show that the amino functionalization is better suited for immobilizing the protein. Strikingly, a considerably higher amount of BMP2 could be immobilized on coated Bioverit® II surfaces compared with coated glass substrates, which was presumably due to the macroscopic roughness of the Bioverit® II substrates. In addition, it was found that the nanoporous silica coatings on Bioverit® II substrates were able to bind more BMP2 than the unstructured ones.

AB - Due to its ability to induce de novo bone formation the differentiation factor bone morphogenetic protein 2 (BMP2) is often used to enhance the integration of bone implants. With the aim of reducing possible high dose side-effects and to lower the costs, in order to produce affordable implants, we developed a simple and fast method for the immobilization of BMP2 on silica-based surfaces using silane linkers which carry amino or epoxy functions. We put an especial emphasis on the influence of the nanoscale surface topography of the silica layer. Therefore, we chose glass (for control experiments) and Bioverit® II (as a typical implant base material) as support materials and coated these substrates with unstructured or nanoporous amorphous silica layers for comparison. Immobilized BMP2 was quantified by two different methods: by ELISA and by a cell-based assay for active BMP2. These tests probe for immunologically and biologically active BMP2, respectively. The results show that the amino functionalization is better suited for immobilizing the protein. Strikingly, a considerably higher amount of BMP2 could be immobilized on coated Bioverit® II surfaces compared with coated glass substrates, which was presumably due to the macroscopic roughness of the Bioverit® II substrates. In addition, it was found that the nanoporous silica coatings on Bioverit® II substrates were able to bind more BMP2 than the unstructured ones.

KW - Bioverit® II

KW - Bone morphogenetic protein 2

KW - Immobilization

KW - Mesenchymal progenitor cells

KW - Nanoporous silica

UR - http://www.scopus.com/inward/record.url?scp=79952193941&partnerID=8YFLogxK

U2 - 10.1016/j.actbio.2010.12.028

DO - 10.1016/j.actbio.2010.12.028

M3 - Article

C2 - 21187169

AN - SCOPUS:79952193941

VL - 7

SP - 1772

EP - 1779

JO - Acta biomaterialia

JF - Acta biomaterialia

SN - 1742-7061

IS - 4

ER -