A Novel Method for Porous Chitosan Scaffold
6
Citation
5
Reference
10
Related Paper
Citation Trend
Abstract:
This study is to develop a novel method for preparation of the chitosan scaffold having interconnected open pore structure and controlled pore distribution. For this, the effects of addition of non-solvent on chitosan solution were estimated. The porous scaffolds were typically prepared by solid-liquid separation and subsequent sublimation of solvent. Alcohol was used as non-solvent for chitosan. The difference of freezing temperature of each of the components induced the liquidliquid and the liquid-solid phase separation via demixing solution (solvent/non-solvent/chitosan). The morphology, heterogeneous pore distribution and mechanical properties of the scaffolds were examined. The addition of non-solvent in chitosan solution was to make the controlled homogeneous micropores and improved interconnectivity between pores without any surface skin layer. For control chitosan scaffold, the pore size was mainly about 80~100 μm. On the contrary, Pore diameters could be controlled mainly within the range 30~100 μm, with a variation of solvent/non-solvent ratio. The number of minute pore (4~25 μm) over chitosan scaffold increased with increasing ratio of non-solvent. New prepared scaffold exhibited larger value of breaking elongation, more elasticity, but less tensile strength than that of control scaffold.Keywords:
Interconnectivity
Elongation
Sublimation
Interconnectivity
Conceptual framework
Cite
Citations (3)
Interconnectivity
Cite
Citations (6)
Electrospinning
Interconnectivity
Cite
Citations (37)
Stereolithographic Bone Scaffold Design Parameters: Osteogenic Differentiation and Signal Expression
Scaffold design parameters including porosity, pore size, interconnectivity, and mechanical properties have a significant influence on osteogenic signal expression and differentiation. This review evaluates the influence of each of these parameters and then discusses the ability of stereolithography (SLA) to be used to tailor scaffold design to optimize these parameters. Scaffold porosity and pore size affect osteogenic cell signaling and ultimately in vivo bone tissue growth. Alternatively, scaffold interconnectivity has a great influence on in vivo bone growth but little work has been done to determine if interconnectivity causes changes in signaling levels. Osteogenic cell signaling could be also influenced by scaffold mechanical properties such as scaffold rigidity and dynamic relationships between the cells and their extracellular matrix. With knowledge of the effects of these parameters on cellular functions, an optimal tissue engineering scaffold can be designed, but a proper technology must exist to produce this design to specification in a repeatable manner. SLA has been shown to be capable of fabricating scaffolds with controlled architecture and micrometer-level resolution. Surgical implantation of these scaffolds is a promising clinical treatment for successful bone regeneration. By applying knowledge of how scaffold parameters influence osteogenic cell signaling to scaffold manufacturing using SLA, tissue engineers may move closer to creating the optimal tissue engineering scaffold.
Interconnectivity
Stereolithography
Cite
Citations (227)
This report looks forward to examining selected representative cases of initiatives already
implemented in Europe or proposed for the short term, that seek to improve interconnectivity among
transport networks and making access for passengers easier. The goal is to identify existing good
practice and potential solutions, analyse these solutions and establish their likely contribution to
improved interconnectivity in European transport networks, and also to identify existing problems still
to be solved.
Interconnectivity
Deliverable
Cite
Citations (0)
Scaffold-based bone tissue engineering aims to repair/regenerate bone defects. Such a treatment concept involves seeding autologous osteogenic cells throughout a biodegradable scaffold to create a scaffold-cell hybrid that may be called a tissue-engineered construct (TEC). A variety of materials and scaffolding fabrication techniques for bone tissue engineering have been investigated over the past two decades. This review aims to discuss the advances in bone engineering from a scaffold material point of view. In the first part the reader is introduced to the basic principles of bone engineering. The important properties of the biomaterials and the scaffold design in the making of tissue engineered bone constructs are discussed in detail, with special emphasis placed on the new material developments, namely composites made of synthetic polymers and calcium phosphates. Advantages and limitations of these materials are analysed along with various architectural parameters of scaffolds important for bone tissue engineering, e.g. porosity, pore size, interconnectivity and pore-wall microstructures.
State of art
Cite
Citations (964)
There is an enduring and unmet need for a bioactive, loadbearing tissue-engineering scaffold, which is biocompatible, biodegradable and capable of facilitating and promoting osteogenesis when implanted in vivo.This study set out to develop a biomimetic scaffold by incorporating osteoinductive hydroxyapatite (HA) particles into a highly porous and extremely biocompatible collagenbased scaffold developed within our laboratory over the last number of years to improve osteogenic performance.Specifically we investigated how the addition of discrete quantities of HA affected scaffold porosity, interconnectivity, mechanical properties, in vitro mineralisation and in vivo bone healing potential.The results show that the addition of HA up to a 200 weight percentage (wt%) relative to collagen content led to significantly increased scaffold stiffness and pore interconnectivity (approximately 10 fold) while achieving a scaffold porosity of 99%.In addition, this biomimetic collagen-HA scaffold exhibited significantly improved bioactivity, in vitro mineralisation after 28 days in culture, and in vivo healing of a critical-sized bone defect.These findings demonstrate the regenerative potential of these biodegradable scaffolds as viable bone graft substitute materials, comprised only of bone's natural constituent materials, and capable of promoting osteogenesis in vitro and in vivo repair of critical-sized bone defects.
Interconnectivity
Cite
Citations (247)
A novel fabrication of degradable scaffold is presented by using several biomaterials and growth factor (GF). Chitosan fibers can be braided into the internal fiber microstructure of the scaffold by a three-dimensional braiding (3DB) method, and rapid prototype & rapid tools techniques can be used to rapidly fabricate the outer shape mold of the scaffold. The scaffolds with 3D fiber architecture had obviously accelerated bone regeneration in comparison with the control. In detail, the materials biodegraded inside and outside and the bone ingrowth first occurred along the chitosan fibers in the scaffold. In summary, the method in this paper not only can be easily shaped but also cannot change the bio-properties of materials and GF since it does not need high temperature sintering and not produce heat, so the actions of the several biomaterials for bone regeneration interacted simultaneously through the interconnectivity macrochannels in the in-vivo scaffolds, which left by the biodegradation of the internal fiber.
Interconnectivity
Template
Cite
Citations (0)
The role of the Trans-European network as an integrated international system is compromised due to poor interconnectivity. Improved interconnections can result in more competitive multi-modal alternatives to uni-modal road transportation and contribute to CO2 emissions reduction. However, the fact is that nowadays 73% of all kilometres completed through long-distance trips in Europe are made by road. One of INTERCONNECT goals was to investigate to what extent reducing interconnectivity costs (between different modes and between local and long-distance networks) may result in an optimised transport system, induce modal shifts towards rail and contribute to decrease CO2 emissions. Conclusions indicate that although these impacts are likely to happen, depending on which specific strategies are adopted to reduce interconnectivity costs, rebound effects may also appear, thereby compromising any potential benefits.
Interconnectivity
Modal shift
Transport Network
Cite
Citations (1)
Interconnectivity of transport networks is a major aim addressed in transport policy today. It refers to different spatial scales and different traffic systems, implying different policy settings. The latter situation explains why interconnectivity as a concept is poorly defined in a generic sense. The paper addresses interconnectivity at a conceptual and operational level, and attempts to identify major generic aspects. Further, it considers interconnectivity in a policy context, by emphasizing its multi‐actor setting. In an empirical case study, the interconnectivity of particular Dutch cities with London is explored, while focusing on the rail and airline system. The paper concludes with a number of interesting issues for future research.
Interconnectivity
Empirical Research
Cite
Citations (14)