Surface modification of polycaprolactone-tricalcium phosphate bioscaffold and design of functional osteogenesis stimulated scaffold carrier

• Main Authors: Hsiu Chen Wang, 王修誠
• Other Authors: M. Y. Lee
• Format: Others
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/76812891251504032869

碩士 === 長庚大學 === 機械工程學系 === 99 === Bone tissue engineering is a key technique for bone defects repair. Polycaprolactone (PCL) is a common material used in tissue engineering because of its biocompatibility. However, the mechanical strength and surface hydrophilicity of PCL scaffold are not good for cell attachment and proliferation. Therefore, the aim of this study was to design and fabricate a PCL composite scaffold combined with β-tricalcium phosphate (β-TCP) using selected laser sintering (SLS) technique for increasing mechanical strength. In addition, this study coated type I collagen on the PCL-TCP scaffold for surface modification. The another aim of this study was to fabricate a PCL scaffold combined with piezoceramics buzzer to be a functional osteogenesis stimulated scaffold carrier for stimulating bone regeneration in human body. The first part of this study was to design and fabricate PCL (control group), PCL-TCP (experimental group A), and type I collagen-coated PCL-TCP (experimental group B) scaffolds. The scanning electron microscope (SEM) and energy dispersive spectrometer (EDS) were used to assess the distribution of TCP in composite scaffolds. In the second part, scaffold characteristics analysis and in vitro experiments were performed for determining the properties of scaffolds. The experimental results showed the compressive moduli of control group, experimental group A, and experimental group B were 6.77 ± 0.196 MPa, 13.66 ± 0.188 MPa, and 13.74 ± 0.318 MPa, respectively. There was a statistically significant difference (p< 0.05) between control group and experimental group A in compressive modulus. This result demonstrated that the combination of PCL and TCP could increase the mechanical strength. Moreover, the contact angles of scaffolds were 120.87° ± 0.953°, 117.69° ± 2.292°, and 73.35° ± 1.840°, respectively. There was a statistically significant difference (p< 0.05) between experimental group A and experimental group B in contact angle. The result of swelling ratio measurement showed that the PCL-TCP scaffold coated with type I collagen could enhance swelling ratio for 18.66 %, and there was a statistically significant difference (p< 0.05) between experimental group A and experimental group B. Both the results of contact angle and swelling ratio measurement demonstrated that the PCL-TCP scaffold coated with type I collagen could improve the surface hydrophilicity. The results of MTS and alkaline phosphatase (ALP) assay showed that experimental group B expressed the better proliferation and ossification ability. The third part of this study was to design and fabricate a functional osteogenesis stimulated scaffold carrier. The result of functional test demonstrated that functional osteogenesis stimulated scaffold carrier can be induced vibration at frequency 86.5 kHz. This study had fabricated PCL-TCP composite scaffold using SLS technique, and demonstrated that combination of PCL and TCP could increase the mechanical strength. In addition, the results of surface hydrophilicity and in vitro experiment expressed that type I collagen-coated PCL-TCP scaffold were better than PCL-TCP scaffold. The results demonstrated that the PCL-TCP scaffold coated with type I collagen could improve the surface hydrophilicity and enhance bone cell ossification ability. Finally, The PCL scaffold carrier and piezoceramics buzzer were successfully combined to be a functional osteogenesis stimulated scaffold carrier.