MICRO-AND NANOSPHERES FOR TISSUE ENGINEERING - Micro and Nanotechnologies in Engineering Stem Cells and Tissues - page 212

scaffold-free, cell-patterned structure. 111-113 This so-called magnetic force-based
tissue engineering strategy showed potential to construct 3D cellularized tissues even
without using monolithic scaffolds.
9.4 CONCLUSIONS
Micro- and nanospheres have evolved as powerful tools in the design of novel
biomaterials for controlled delivery and tissue engineering and regeneration. Strate-
gies using micro- and nanospheres display several advantages compared with
conventional monolithic biomaterials, such as (1) an improved performance in
controlled and sustained delivery of therapeutic agents, signaling biomolecules,
and even (stem) cells; (2) improved structural or mechanical properties of bulk
scaffold by using spheres as porogens or reinforcement phase to introduce porosity or
improve mechanical strength; (3) upregulated control over dedicated biochemical
processes by using micro- and nanospheres as compartmentalized microreactors; and
(4) the possibility to prepare self-assembling colloidal systems that can be used as
injectable or moldable formulations to be applied using minimally invasive surgery.
ACKNOWLEDGMENTS
The authors are grateful for the support from funding KNAW, China-Netherlands
Programme Strategic Alliances (PSA) (No.2008DFB50120) and the Dutch Tech-
nology Foundation STW, Applied Science Division of NWO, and the Technology
Program of the Ministry of Economic Affairs (VENI grant 08101).
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