Surface tissue scaffolds

CNTs are especially valued as implant materials thanks to their novel mechanical properties and surface functionability.35 They have been found to make an ideal scaffold for the growth of bone tissue.36 Moreover, many tissues and organs require bio-compatible substrates to facilitate tissue growth and implantation. The fabric made fom CNTs serves as an efficient tissue scaffold.36 Several publications demonstrate that CNTs can be used as a substrate for neuronal growth, and that modifications of the CNTs can be employed to modulate the development of neurons. This suggests that it may be possible to employ suitably functionalized CNTs as neural prostheses in neurite regeneration.35 Lipid bilayers have been developed using a nanotube template. 

Simulating the appropriate size, geometry and architecture of natural extracellular matrix is of critical importance for tissue engineering and three-dimensional (3D) tissue culture. Essential parameters for tissue scaffolds are microstructures, porosity, pore size, surface area / surface chemistry and mechanical properties (35). With these properties in mind, several iterations of scaffolds have been produced and evaluated. 

XPS is used to analyze the elemental composition of polymer surfaces. In this technique, the sample is irradiated with a high-energy monochromatic X-ray and the core level electrons ejected from the sample (called photoelectrons) are detected. The energy of the photoelectrons ejected from the sample depends on the elements present on the sample surface. PGA scaffolds are used in bone tissue engineering, and in order to improve the osteoconduction of the PGA scaffold, hydroxyapatite nanoparticles are coated on the polymer. XPS is a reliable method to verify the deposition of HA nanoparticles on PGA surface [37]. AES is more surface-sensitive than XPS. In this technique, a beam... 

The 1976 amendment sought to define medical devices. These definitions are worth considering because they have created challenges for developers of biotextiles today. At the time of their crafting, the authors of the definitions did not anticipate the advent of devices such as tissue scaffolds, bio-absorbable materials or textiles with biologically modified surfaces ... 

Among the various useful polymer materials, recent years have witnessed a strong rise in the use of polycarbonates as a material of choice in biomedical applications. Lee et al. examined the behavior of MG63 osteoblast-like cells cultured on a polycarbonate (PC) membrane surface with different micropore sizes (200 nm-8.0 pm) [29]. Welle et al. described electrospun aliphatic polycarbonate as tailored tissue scaffold, where the photochemical bulk modification indicates the possibility of spatial control of the biodegradation rate [30]. In an earlier section we mentioned the use of track-etched polycarbonate membranes that have been introduced as substrate for perfused cell culture in 3D format [31]. The microscopic cavities of the polymer scaffold provide three-dimensionality and nanoscopic pores provide nourishment to the cell culture from all around. Therefore, it is interesting to develop polycarbonate chemistry so that the desired functional groups and molecules can be introduced to the surface for obtaining cell substrate response. 

Nanostructured carbon surfaces and scaffolds have been shown to not hinder but significantly promote cell growth. For example, neural cells and mouse fibroblast cells were successfully cultured on CNT scaffolds. The findings encourage the application of nanostructured carbon devices as implantable sensors and tissue scaffolds. For instance, ectopic formation of bone tissue was observed after MWCNT scaffolds were implanted in muscle tissue, suggesting that the nanostructured carbon substrates could encourage cells to grow within the body. ... 

Improvement of tissue scaffolding by surface grafting with gelatin, demonstrated. 

Grant, P. V., C. M. Vaz, P. E. Tomlins, L. Mikhalovska, S. Mikhalovsky, S. James, and Vadgama, P. (2006). Physical characterization of a polycaprolactone tissue scaffold. In Surface Chemistry in Biomedical and Environmental Science. 

Electrospinning is increasingly being used to produce fibres for tissue culture scaffolds, which exhibit important advantages when compared with foams. Firstly, the interconnectivity of voids available for tissue ingrowth is perfect, whereas in the case of foams some cavities can be dispersed in the matrix and hence closed also fenestration between adjacent cavities can be too small to allow for cell permeation. Secondly, ultrathin fibres produced by electrospinning offer an unsurpassed surface volume ratio among applied tissue scaffolds [300, 301]. 

Jozwiak, A. B., C. M. Kielty, and R. A. Black. 2008. Surface functionalization of polyurethane for the immobilisation of bioactive moieties on tissue scaffolds. 7. Mater. Chem. 18 2240-2248. 

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