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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.

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We report a surfactant free route to synthesize hollow mesoporous bioactive glass nanoparticles at ambient atmospheric condition. The synthesized particles contain hollow core as a result of mild acid mediated removal of calcium carbonate nanoparticles used as hard template. Removal of template was confirmed through FTIR and XRD while round morphology and sizes below 100 nm could be observed by TEM. In addition, N 2 adsorption and desorption analysis confirmed hollow and mesoporous nature of the bioactive glass shell. Interestingly, post removal of template, particles reported higher surface area, pore volume and pore diameter along with decrease in surface charge. Deposition of hydroxyapatite on hollow bioactive glass in Simulated Buffer Fluid (SBF) could be observed from Day 7 of immersion while well-developed hydroxyapatite depositions could be observed by Day 30. This proved bioactivity of the material while cytotoxicity analysis on Human Osteosarcoma cell line (U2OS) through MTT assay proved the biocompatible nature of the hollow bioactive glass particle.