The self-assembly of bolaamphiphile 1 into nanotubes containing a nanostructured electron donor/acceptor heterojunction is reported. In 10% MeOH/H(2)O, the tetraphenylporphyrin (TPP) and 1,4,5,8-naphthalenetetracarboxylic acid diimide chromophores engage in strong J-type π-π interactions within monolayer rings that further stack into the nanotube assemblies. In 10% MeOH/H(2)O at pH 1 or 11 or in pure MeOH, assembly is driven exclusively by the TPP ring, leading to the formation of nonspecific, unstructured aggregates. Steady-state, time-resolved fluorescence and femtosecond transient absorption spectroscopy revealed a strong dependence of the fluorescence decay and electron-transfer/charge-recombination time constants on the nature of the assemblies. These studies highlight the importance of local nanostructure in determining the photophysical properties of optoelectronic materials.

Peptide 1 with an Aβ42 amyloid nucleating core demonstrates step-wise self-assembly in water. Variation of temperature or solvent composition arrests the self-assembly to give metastable nanoparticles, which undergo self-assembly on gradual increase in temperature and eventually produce kinetically controlled nanofibers and thermodynamically stable twisted helical bundles. Mechanical agitation of the fibers provided access to short seeds with narrow polydispersity index, which by mediation of seeded supramolecular polymerization establishes perfect control over the length of the nanofibers. Such pathway dependence and the length control of the supramolecular peptide nanofibers is exploited to tune the mechanical strength of the resulting hydrogel materials.

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 hydrogels have recently emerged as potential biomaterials for designing synthetic scaffolds in tissue engineering. We demonstrate pathway-controlled self-assembly of peptide amphiphile 1 to furnish kinetically controlled nanofibers (1 NF ) and thermodynamically stable twisted helical bundles (1 TB ). These supramolecular nanostructures with varied persistence lengths promote in situ mineralization to yield templated bioactive glass composites, 1 NF BG and 1 TB BG − resorbable, mesoporous, and degradable biomaterials as bone scaffolds. The structural features of the hydrogel composites are investigated extensively with microscopic characterization, energydispersive X-ray spectroscopy, Raman spectroscopy, and XPS to conclude 1 TB BG as the superior material with higher percentage of open network structures as obtained from ratios of nonbridging and bridging oxygen. The hydrogel composites show excellent dynamic and self-healing behavior from rheological studies, especially the elastic modulus of 1 TB BG being almost comparable to natural bone. Upon incubation in simulated body fluid, the bioglass composites illustrate tunable bioactive response mediated by the structural and topological control to induce the deposition of multiphasic calcium phosphate along with octacalcium phosphate and carbonate hydroxyapatite. Finally, such spatiotemporal composites facilitate stiffness-controlled osteoblast cellular interactions to support U2OS subsistence in the hydrogel matrix, highlighting their potential as a substrate for osteoblast growth for prolonged culture periods and in 3D bone tissue modeling.