Patterning And Three-Dimensional Fabricating Of Electrospun Composite Nanofibers

The flourish of tissue engineering provides a solid guarantee for the health and development of human beings.As one of the three key elements of tissue engineering,scaffolds are arts of human engineering wisdom and have experienced a booming development in the past decades,stepping on a way of biomimetic fabrication nowadays.Owing to its capacity of preparing nanofibers which could simulate the structure of extracellular matrix,electrospinning was appreciated by the biomaterial researchers for a long time.However,the lack of efficient methods to fabricate three dimensional structure bring this technic into a dilemma in tissue engineering applications,especially in hard tissue repairing.To relieve this predicament and find new approaches for 3D structure preparing,lots of effort were focused on the patterning and 3D structure fabrication of electrospun nanofibers in the paper.For the purpose of preparing patterned nanofiber meshes which consisted of aligned nanofibers,a stainless steel mesh was used as template to collect nanofibers.The conductive polymer polyaniline was doped into nanofibers to manufacture conductive patterned nanofiber mesh at the same time.A series of tests were conducted to examine properties of nanofibers.And then,PC12-L cells were seeded on nanofiber meshes to investigate the influence of aligned nanofiber and conductive polymer doping on the differentiation behavior of these cells.Results indicate aligned fiber and conductive polymer doping could act both alone and synergistically to promote the PC12-L cells differentiating into neuron like cells.Hydroxyapatite doped composite nanofiber meshes which have penetrating holes were prepared on stainless steel mesh template.3D scaffolds with macro to micro hierarchical connecting-hole system were successfully fabricated though a layer-by-layer assembling with the help of the tailor-made binder.Based on the theory that bisphosphonates which have P-C-P bone structure could bind to Ca2+ with strong affinity,hydroxyapatite-polycaprolactone composite nanofiber scaffold were loaded with alendronate.The alendronate loaded scaffold show potent effect on upregulating osteogenic gene expression level of human fetal osteoblasts(hFOB).Patterned biocompatible magnetic nanofiber meshes were obtained by using stainless steel as template collector.A magnetic meshes based non-touch method to fabricate 3D structure with macro to micro hierarchical connecting-hole system were put forward.By way of modulating the doping concentration of magnetic nanoparticles,magnetic meshes with different response capabilities to exterior magnetic field could be prepared.Based on this results,a 3D culture system with dynamic mechanical loading property was present in the end.In conclusion,a series of job were carried out to discover new methods of preparing three dimensional structure of electrospun nanofibers.Three types of composite nanofibers were fabricated by electrospinning and relevant 3D structure fabricating methods were present at the same time,which could do help to the tissue engineering application of electrospinning.