title: Tuning the erosion rate of artificial protein hydrogels through control of network topology.
abstract: Erosion behaviour governs the use of physical hydrogels in biomedical applications ranging from controlled release to cell encapsulation. Genetically engineered protein hydrogels offer unique means of controlling the erosion rate by engineering their amino acid sequences and network topology. Here, we show that the erosion rate of such materials can be tuned by harnessing selective molecular recognition, discrete aggregation number and orientational discrimination of coiled-coil protein domains. Hydrogels formed from a triblock artificial protein bearing dissimilar helical coiled-coil end domains (P and A) erode more than one hundredfold slower than hydrogels formed from those bearing the same end domains (either P or A). The reduced erosion rate is a consequence of the fact that looped chains are suppressed because P and A tend not to associate with each other. Thus, the erosion rate can be tuned over several orders of magnitude in artificial protein hydrogels, opening the door to diverse biomedical applications.
authors.affiliation: Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena 91125, USA. weishen@its.caltech.edu
authors.forename: Wei
authors.initials: W
authors.lastname: Shen
authors.forename: Kechun
authors.initials: K
authors.lastname: Zhang
authors.forename: Julia A
authors.initials: JA
authors.lastname: Kornfield
authors.forename: David A
authors.initials: DA
authors.lastname: Tirrell
mesh_terms: D000595:Amino Acid Sequence; D001672:Biocompatible Materials / Q000737:chemistry; D020100:Hydrogels / Q000737:chemistry*; D008958:Models, Molecular; D011506:Proteins / Q000138:chemical synthesis* / Q000737:chemistry*
chemical_list: D001672:Biocompatible Materials; D020100:Hydrogels; D011506:Proteins