The Experimental Study Of Immobilization Of The Peptides That Specifically Bind To Human Calvarial Osteoblasts On The Titanium Implant Surface

In oral planting applications, the longer healing time makes its application limited due to its inherent biological inactive, especially in the area where the bone is poor. In order to solve the above problem, the titanium surface modification is current research hotspot in order to improve its various features and get better biological activity of the implant to reduce healing time and increase the healing quality. This study aims to covalently immobilize the peptides that specifically bind to human calvarial osteoblastson the titanium substrate surface through chemical methods, compared biological evaluation of the materials, and developed a new research approach and experimental foundation of the biological modification on the surface of titanium implant. The whole study consists of two parts as follows: PartI Imobilize the peptides that specifically bind to human calvarial osteoblastson the titanium substrate surfaceThe surface of the titanium substrate was treated by 3-aminopropylphosphonic acid(APP), and enable them to obtain free amino groups which phosphonic acid group and TiO2 were form covalent bonding; immobilized avidin-biotin-system in material surface trough amide bond by carbodiimide(EDC)-mediated and then through the specific binding between avidin and biotin, to immobilize peptide on the titanium substrate surface. The samples was characterized by environmental scanning electron microscopy(ESEM), fouriertransform infrared spectroscopy(FTIR), x-ray photoelectron spectroscopy(XPS) and immunofluorescence.The titanium disk has a rough and pore-rich surface which treated by the APP, the bottom wall consist of microscopic pores which the diameter is about 1 to 2 microns. From the result about composition of chemical groups and the change of elements ratio by FTIR and XPS, it has confirm that APP built the self-assembled layer and there are free amino groups on the titanium surface. Finally it can confirm that the specificity recognition peptide was fixed by immunofluorescence. PartII The biological evaluation about human calvarial osteoblasts with the modifycation surface by the specific peptideHuman calvarial osteoblasts were cultured on the smooth titanium disks and modification disks, using confocal laser scanning microscope to observe the cell morphology on the different materials, and then determined by MTT and ALP. Statistical analysis was conducted after arrange the experiment data,then analysis the effect of adhesion and osteogenesis of human calvarial osteoblasts about the materials.Comparation with smooth titanium disk, osteoblast distribution is more dense, the cell morphology present a polygon, and cell have more cellular pseudopod. Then the results by MTT, ALP determined showed that osteoblasts has better proliferation and osteogenesis on the modification titanium disk. Conclusion The specificity peptide can be fixed on the titanium disk which was treated by APP and the BAS. Through cytological evalution, the modification surface has good biological activity, and developed a new research approach and experimental foundation of the biological modification on the surface of titanium implant.