RESPONSIVE GELS FORMED BY THE SPONTANEOUS SELF-ASSEMBLY OF PEPTIDES INTO POLYMERIC BETA-SHEET TAPES

Molecular self-assembly is becoming an increasingly popular route to n ew supramolecular structures and molecular materials(1-7). The inspira tion for such structures is commonly derived from self-assembling syst ems in biology. Here we show that a biological motif, the peptide beta -sheet, can be exploited in designed oligopeptides that self-assemble into polymeric tapes and with potentially useful mechanical properties . We describe the construction of oligopeptides, rationally designed o r based on segments of native proteins, that aggregate in suitable sol vents into long, semi-flexible beta-sheet tapes. These become entangle d even at low volume fractions to form gels whose viscoelastic propert ies can be controlled by chemical (pH) or physical (shear) influences. We suggest that it should be possible to engineer a wide range of pro perties in these gels by appropriate choice of the peptide primary str ucture.