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3D bioprinting for tissue engineering: Stem cells in hydrogels

            gical demand for bespoke solutions.                Author Contributions
               Material compatibility with such advanced systems
            must also be assessed. A physiologically relevant sca-  All authors  contributed towards the  writing of this
            ffold must be able to support and guide cell growth   review paper. We thank Dr. James Bowen for his in-
            and differentiation both chemically and physically. As   sights and discussions.
            well as creating complex blends of bioinks, this would   Conflict of Interest and Funding
            require heterogeneous material fabrication  and  preci-
            sion-printing to create organized gradients or complex   No  conflict of interest was reported by all authors.
            patterns of cells and functional  motifs which  mimic   This work was supported by the Medical Research
            native ECM  more  closely. One approach  currently   Council (MR/K026453/1, MAB and NM) and the En-
            being explored to meet these requirements is the use   gineering  and  Physical Sciences Research  Council
            of smart  materials, i.e.,  materials that are able to   (EP/K504610/1, GZT).
            change their shape, mechanical strength and permea-  References
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            14                          International Journal of Bioprinting (2016)–Volume 2, Issue 1
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