Fabrication of channeled scaffolds with ordered array of micro-pores through microsphere leaching and indirect Rapid Prototyping technique

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Advanced scaffold fabrication techniques such as Rapid Prototyping (RP) are generally recognized to be advantageous over conventional fabrication methods in terms architectural control and reproducibility. Yet, most RP techniques tend to suffer from resolution limitations which result in scaffolds with uncontrollable, random-size pores and low porosity, albeit having interconnected channels which is characteristically present in most RP scaffolds. With the increasing number of studies demonstrating the profound influences of scaffold pore architecture on cell behavior and overall tissue growth, a scaffold fabrication method with sufficient architectural control becomes imperative. The present study demonstrates the use of RP fabrication techniques to create scaffolds having interconnected channels as well as controllable micro-size pores. Adopted from the concepts of porogen leaching and indirect RP techniques, the proposed fabrication method uses monodisperse microspheres to create an ordered, hexagonal closed packed (HCP) array of micro-pores that surrounds the existing channels of the RP scaffold. The pore structure of the scaffold is shaped using a single sacrificial construct which comprises the microspheres and a dissolvable RP mold that were sintered together. As such, the size of pores as well as the channel configuration of the scaffold can be tailored based on the design of the RP mold and the size of microspheres used. The fabrication method developed in this work can be a promising alternative way of preparing scaffolds with customized pore structures that may be required for specific studies concerning cell-scaffold interactions.

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The authors gratefully acknowledge the financial support of both the Singapore Agency for Science, Technology and Research (ASTAR) through the Singapore-University of Washington Alliance (SUWA) programme and Nanyang Technological University (NTU).

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Correspondence to J. Y. Tan.

Electronic supplementary materials

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Illustration on the alignment of monodispersed microspheres into a hexagonal arrangement under ultrasound agitation (WMV 1786 kb)

The alignment of monodispersed microspheres under ultrasound agitation showing multilayer stacking of microspheres (WMV 8814 kb)

Supplementary materials (Video clip 1

Illustration on the alignment of monodispersed microspheres into a hexagonal arrangement under ultrasound agitation (WMV 1786 kb)

Supplementary materials (Video clip 2

The alignment of monodispersed microspheres under ultrasound agitation showing multilayer stacking of microspheres (WMV 8814 kb)

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Tan, J.Y., Chua, C.K. & Leong, K.F. Fabrication of channeled scaffolds with ordered array of micro-pores through microsphere leaching and indirect Rapid Prototyping technique. Biomed Microdevices 15, 83–96 (2013).

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  • Tissue Engineering
  • Scaffold fabrication
  • Rapid prototyping
  • Microsphere leaching