DNA-directed self-assembly of shape-controlled hydrogels.

1] Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, Massachusetts 02115, USA [2] Department of Medicine, Center for Biomedical Engineering, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA [3] Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Nature Communications (Impact Factor: 10.74). 09/2013; 4:2275. DOI: 10.1038/ncomms3275
Source: PubMed

ABSTRACT Using DNA as programmable, sequence-specific 'glues', shape-controlled hydrogel units are self-assembled into prescribed structures. Here we report that aggregates are produced using hydrogel cubes with edge lengths ranging from 30 μm to 1 mm, demonstrating assembly across scales. In a simple one-pot agitation reaction, 25 dimers are constructed in parallel from 50 distinct hydrogel cube species, demonstrating highly multiplexed assembly. Using hydrogel cuboids displaying face-specific DNA glues, diverse structures are achieved in aqueous and in interfacial agitation systems. These include dimers, extended chains and open network structures in an aqueous system, and dimers, chains of fixed length, T-junctions and square shapes in the interfacial system, demonstrating the versatility of the assembly system.

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