Clinical neural scaffold for olfactory ensheathing cells Thesis

Clinical neural scaffold for olfactory ensheathing cells - Thesis Example It is known that UV can degrade polymer. Previous studies showed that UV wavelength of 250 nm can cleave poly (methyl methacrylate), a standard polymer to its monomer methyl methacrylate and gases (Srinivasan, Braren, & Casey, 1990). Increasing the duration of the sterilization also increased damage to the polymer structure (Shearer, Ellis, Perera, & Chaudhuri, 2005)Recently, UV has been shown to induce significant degradation of PLGC and P(LLA-CL) nanofibers (Yixiang, Yong, Liao, Chan, & Ramakrishna, 2008). The degradation by UV of electrospun nanofibers can be exploited for the fabrication of 3D nanofibrous scaffolds with micropores. For the ethanol sterilization, the global structure of the fibrous mesh shrank in size, detaching part of the fastened portion of the mesh from the membrane insert Investigation on two different scaffolds showed that ethanol sterilization also resulted in damage to the polymer (Shearer, Ellis, Perera, & Chaudhuri, 2005). Digital image analysis from SEM images, showed that average fibre diameter expanded by 21.1% (EOa= 1.08Â µm; EOb=0.89 Â µm) (Error: Reference source not found). ... been the sterilization process of choice in electrospun PLGA nanofiber scaffold for inducing the continuous differentation of mesenchymal stem cells, chondrogenic and osteogThe PMMA membrane inserts were inert to all sterilization processes. enic lineages (Xin, Hussain, & Mao, 2007). Ethylene oxide sterilization had no effect on the inherent viscosity, glass transition temperature and mechanical properties of 82:18 poly(l-lactic acid)-poly(glycolic acid) used on craniofacial plates. The in vitro hydrolysis rates and mechanical strength loss were not also affected providing evidence that ethylene oxide sterilization cycle agrees well with copolymer plates and thus should not affect clinical performance (Pietrzak, 2010). 14.2 Cellular Response on Scaffold Functionalization Scaffolds to encourage cell growth and differentiation must mimic not only the biological but also the physical properties of the extracellular matrix. Functionalization of the engineered scaffolds aims to improve su rface properties towards cell differentiation and proliferation. The high fidelity of the submicron scale features and dimension in the PLGA electrospun fibres mesh after coating and air-drying was verified through SEM (Error: Reference source not foundC, E, G, I). The effect of nanofibres functionalization was then studied by analysing the cellular responses on the nanofibres.After four days in culture, the responses of seeded purified OEC on the four types of functionalization were investigated using immunofluorescence microscopy. All four coatings (collagen, laminin, pLL and pDL) promoted cell attachment, when compared to the non-functionalized PLGA electrospun nanofibres mesh (Error: Reference source not foundD, F, H, J vs. Error: Reference source not foundA). All four