Enzymes are the most efficient catalysts in nature that possess an impressive range of catalytic activities albeit limited by the stability in adverse condition. Functional peptides have emerged as alternative...

Self-sorting is a spontaneous phenomenon that ensures formation of complex yet ordered multicomponent system and conceptualizes the design of artificial and orthogonally functional compartments. In the present study, we envisage...

Peptide 1 with an Aβ42 amyloid nucleating core and a photodimerizable 4methylcoumarin moiety at its N terminus demonstrates the step-wise self-assembly in water to form nanoparticles, with eventual transformation into 1D nanofibers. Addition of γ-cyclodextrin to 1 with subsequent irradiation with UV light at 320 nm resulted in morphological conversion to free-standing 2D nanosheets mediated by the host−guest interaction. Mechanical agitation of the 1D and 2D nanostructures led to seeds with narrow polydispersity indices, which by mediation of seeded supramolecular polymerization found seamless control over the dimensions of the nanostructures. Such structural and temporal control to differentiate the pathway was exploited to tune the mechanical strength of hierarchical hydrogel materials. Finally, the dimensional characteristics of the positively charged peptide fibers and sheets were envisaged as excellent exfoliating agents for inorganic hybrid materials, for example, MoS 2 .

Reinforcement owing to inner stress formation is of supreme importance in life and is the basis for biomechanical pathways, especially in the contractile materials resembling muscles. Cells strengthen their contiguous matrix by pulling thin actin filaments associated with bundles of myosin with molecular motors promoting rapid fluidization and dynamic stiffening of the cytoskeleton. Herein, we demonstrate an elegant synthetic design of a peptide−polymer conjugate network that exhibits multiple hierarchical control over its stiffening. Dynamic Schiff base crosslinking of semi-flexible peptide nanofibers with the thermo-responsive poly(N-isopropylacrylamide) (PNIPAM) copolymer endows a covalent network. Further, the photo-dimerizable 4-methylcoumarin moieties at the core of peptide nanofibers can also be reversibly photo-fixated with the choice of light. The conjugates exhibit macroscopic heatstiffening response by generating inner stress through a coil-to-globule transition owing to the lower critical solution temperature of PNIPAM. Moreover, the covalently crosslinked network noticeably stiffens in response to applied shear stress that can be further ramped up in the photo-fixated peptide nanofibers. Finally, an excellent biocompatibility toward U2OS cell lines validates these as ideal biomimetic and adaptive materials. Overall, we report for the first time a synthetic strain-stiffening network based on a nonequilibrium self-assembled peptide fiber toward non-linear biomechanics analogous to the actinomyosin network ubiquitous in cells and tissues.