View Item 
      •   Home
      • 1. Schools
      • College of Engineering
      • School of Mechanical and Aerospace Engineering (MAE)
      • MAE Student Reports (FYP/IA/PA/PI)
      • View Item
      •   Home
      • 1. Schools
      • College of Engineering
      • School of Mechanical and Aerospace Engineering (MAE)
      • MAE Student Reports (FYP/IA/PA/PI)
      • View Item
      JavaScript is disabled for your browser. Some features of this site may not work without it.
      Subject Lookup

      Browse

      All of DR-NTUCommunities & CollectionsTitlesAuthorsBy DateSubjectsThis CollectionTitlesAuthorsBy DateSubjects

      My Account

      Login

      Statistics

      Most Popular ItemsStatistics by Country/RegionMost Popular Authors

      About DR-NTU

      Fabrication and patterning of alginate microspheres for 3D bioprinting

      Thumbnail
      YS_FYPREPORT.pdf (4.163Mb)
      Author
      Loh, Yue Siew
      Date of Issue
      2017
      School
      School of Mechanical and Aerospace Engineering
      Abstract
      Alginate microspheres can provide a three-dimensional (3D) space for cell adhesion and proliferation for 3D bioprinting. Monodispersed microspheres can be patterned into complex 3D shapes with controllable features. In this project, the fabrication of monodispersed alginate microspheres through simple extrusion method were presented. The fabrication parameters include the height of droplet release, the concentration of alginate droplets, the concentration of the calcium chloride (CaCl2) bath, and the mechanical rotation speed to agitate the CaCl2 bath. The best combination of the parameters tested was found to be 1 mm height of droplet release, 3% (wt/v) of alginate, 50 mM of CaCl2 solution and 150 rpm mechanical agitation speed. Nevertheless, some of the alginate droplets were floating on the CaCl2 solution, producing deformed alginate beads that are not spherical. A new method of using ethanol in the CaCl2 bath was explored to prevent the alginate droplets from floating on the surface of the bath. Spherical alginate spheres can be fabricated in a solution of 50 mM CaCl2 in 23% ethanol. The size of the spheres were ~2 mm, which can be reduced to 1 mm after post-crosslinking in a 50 mM CaCl2 solution. Following the alginate microspheres fabrication, the microspheres were patterned via two techniques, i.e. direct and indirect extrusion patterning methods. The bioink for these patterning methods was made up of alginate microspheres encapsulated in partially cross-linked alginate hydrogel, which produced a self-supporting structure with immediate gelation upon immersing in a CaCl2 bath. In the direct extrusion patterning method, various shapes were producible. In the indirect extrusion patterning method, a pluronic F127 mold was printed before incorporating bioink. The two patterning techniques were both feasible. Although indirect extrusion patterning produced shapes of lesser printing accuracy due to the diffusion of the alginate gel, they can both be performed depending on the design complexity of the desired biological construct. The elastic modulus of the cross-linked bioink was found to be higher than those of alginate hydrogel without spheres via a compression test. Fabricating and patterning alginate spheres via simple and inexpensive methods open up more possibilities to introducing hydrogel spheres into 3D bioprinting.
      Subject
      DRNTU::Engineering::Mechanical engineering
      Type
      Final Year Project (FYP)
      Rights
      Nanyang Technological University
      Collections
      • MAE Student Reports (FYP/IA/PA/PI)

      Show full item record


      NTU Library, Nanyang Avenue, Singapore 639798 © 2011 Nanyang Technological University. All rights reserved.
      DSpace software copyright © 2002-2015  DuraSpace
      Contact Us | Send Feedback
      Share |    
      Theme by 
      Atmire NV
       

       


      NTU Library, Nanyang Avenue, Singapore 639798 © 2011 Nanyang Technological University. All rights reserved.
      DSpace software copyright © 2002-2015  DuraSpace
      Contact Us | Send Feedback
      Share |    
      Theme by 
      Atmire NV
       

       

      DCSIMG