title: Fabrication of mineralized polymeric nanofibrous composites for bone graft materials.
abstract: Poly-L-lactic acid (PLLA) and PLLA/collagen (50% PLLA+50% collagen; PLLA/Col) nanofibers were fabricated using electrospinning. Mineralization of these nanofibers was processed using a modified alternating soaking method. The structural properties and morphologies of mineralized PLLA and PLLA/Col nanofibers were investigated using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and contact angle measurements. Human bone-derived osteoblasts were cultured on the materials for up to 1 week to assess the biological properties of the nanofibrous composites. Cell attachment on these nanocomposites was also tested within 1 h of culture at room temperature. The mechanical properties of the cell-nanocomposite constructs were determined using tensile testing. From our results, the bone-like nano-hydroxyapatite (n-HA) was successfully deposited on the PLLA and PLLA/Col nanofibers. We observed that the formation of n-HA on PLLA/Col nanofibers was faster and significantly more uniform than on pure PLLA nanofibers. The n-HA significantly improved the hydrophilicity of PLLA/Col nanofibers. From the results of cell attachment studies, n-HA deposition enhanced the cell capture efficacy at the 20-minute time point for PLLA nanofibers. The E-modulus values for PLLA+n-HA with cells (day 1 and day 4) were significantly higher than for PLLA+n-HA without cells. Based on these observations, we have demonstrated that n-HA deposition on nanofibers is a promising strategy for early cell capture.
authors.affiliation: Graduate Programme in Bioengineering, Centre for Life Sciences, National University of Singapore Graduate School for Integrative Sciences and Engineering, Singapore.
authors.forename: Michelle
authors.initials: M
authors.lastname: Ngiam
authors.forename: Susan
authors.initials: S
authors.lastname: Liao
authors.forename: Avinash J
authors.initials: AJ
authors.lastname: Patil
authors.forename: Ziyuan
authors.initials: Z
authors.lastname: Cheng
authors.forename: Fengyi
authors.initials: F
authors.lastname: Yang
authors.forename: Miguel J
authors.initials: MJ
authors.lastname: Gubler
authors.forename: S
authors.initials: S
authors.lastname: Ramakrishna
authors.forename: Casey K
authors.initials: CK
authors.lastname: Chan