Mesoporous silica vesicles have been prepared by an ultrasound‐mediated supramolecular templating technique using cetyltrimethylammonium bromide as the surfactant. Cooperative assembly of the surfactant and silicate species near the air–water interface of the cavitating bubbles results in a vesicular morphology. The vesicles are thermally stable, possessing wormhole‐like mesopores and a high surface area.

It is well established that angiogenesis is the process of formation of new capillaries from pre-existing blood vessels. It is a complex process, involving both pro- and anti-angiogenic factors, and plays a significant role in physiological and pathophysiological processes such as embryonic development, atherosclerosis, post-ischemic vascularization of the myocardium, tumor growth and metastasis, rheumatoid arthritis etc. This is the first report of zinc oxide (ZnO) nanoflowers that show significant pro-angiogenic properties (formation of new capillaries from pre-existing blood vessels), observed by in vitro and in vivo angiogenesis assays. The egg yolk angiogenesis assay using ZnO nanoflowers indicates the presence of matured blood vessels formation. Additionally, it helps to promote endothelial cell (EA.hy926 cells) migration in wound healing assays. Formation of reactive oxygen species (ROS), especially hydrogen peroxide (H(2)O(2))-a redox signaling molecule, might be the plausible mechanism for nanoflower-based angiogenesis. Angiogenesis by nanoflowers may provide the basis for the future development of new alternative therapeutic treatment strategies for cardiovascular and ischemic diseases, where angiogenesis plays a significant role.

Monodispersed Fe3O4 nanospheres with hollow interior structures exhibiting high saturation magnetization of 83.0 emu g−1 were fabricated by a facile one-pot route. The fabrication process is very simple with only FeCl3·6H2O and anhydrous NaAc as the reactants in an ethylene glycol solution with no templates or surfactants involved. Field-emission scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and a superconducting quantum interference device magnetometer were used to characterize the morphologies, structures, and properties of the hollow magnetic nanospheres. A plausible mechanism based on oriented attachment and subsequent local Ostwald ripening is proposed. In addition, the experiments of the hollow nanospheres decorated with polyacrylic acids as drug carriers and Rhodamine 6G as a model drug, revealed pH- or salt-responsive release profiles, thus demonstrating the potential of these nanostructures in biomedical applications.

A facile in situ assembly strategy was developed for the fabrication of Pt-Au alloy nanoparticles (NPs) on nitrogen-doped graphene (N-G) sheets, and the as-fabricated Pt-Au/N-G nanocomposites were suitable for electrochemical applications. As characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction analysis and inductively coupled plasma-atomic emission spectroscopy techniques, Pt-Au alloy NPs with an average size of 4-5 nm were uniformly distributed on the N-G surface through intrinsic covalent bonds. The Pt-Au/N-G nanocomposites exhibited excellent electrocatalytic activity and stability towards the methanol oxidation reaction with the highest capability observed for a Pt/Au atomic ratio of 3/1. The unique electrochemical features are distinctive from those of N-free nanocomposites and commercially available Pt/C catalysts, indicative of the alloying effect of Pt-Au and their synergistic interaction with the N-G sheet, which may open up new possibilities for the preparation of N-G-based nanocomposites for other intensive applications as well.

A novel combination of mechanochemical and sonochemical techniques was developed to produce high-surface-area, bio-based calcium carbonate (CaCO3) nanoparticles from eggshells. Size reduction of eggshell achieved via mechanochemical and followed by sonochemical method. First, eggshells were cleaned and ground, then ball milled in wet condition using polypropylene glycol for ten hours to produce fine particles. The ball milled eggshell particles were then irradiated with a high intensity ultrasonic horn (Ti-horn, 20 kHz, and 100 W/cm(2)) in the presence of N,N-dimethylformamide (DMF); decahydronaphthalene (Decalin); or tetrahydrofuran (THF). The ultrasonic irradiation times varied from 1 to 5 h. Transmission electron microscopic (TEM) studies showed that the resultant particle shapes and sizes were different from each solvent. The sonochemical effect of DMF is more pronounced and the particles were irregular platelets of ~10 nm. The BET surface area (43.687 m(2)/g) of these nanoparticles is much higher than that of other nanoparticles derived from eggshells.

A bioinspired mineralization route to prepare self-cleaning cotton fabrics by functionalizing their surface with nanostructured Ag@ZnO is demonstrated herein. In a polyamine-mediated mineralization process, while the nucleation, organization and coating of ZnO is done directly from water-soluble zinc salts under mild conditions, the entrapped polyamine in the ZnO matrix acts as reducing agent to generate Ag(0) from Ag(I) at room temperature. The Ag@ZnO coated cotton fabrics are characterized by FESEM, HRTEM, XRD, and UV-vis-DRS to confirm the formation and coating of Ag@ZnO particles on individual threads of the fabric. The presence of Ag nanoparticles not only enables the ZnO-coated fabrics exhibiting improved photocatalytic property but also allows for visible-light-driven activities. Furthermore, it exhibits efficient antimicrobial activity against both Gram-positive and Gram-negative bacteria. Therefore, besides these multifunctional properties, the polyamine-mediated bioinspired approach is expected to pave way for functionalization of flexible substrates under mild conditions as desirable for the development and fabrication of smart, lightweight, and wearable devices for various niche applications.

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Herein, we present an environmentally benign method capable of mineralization and deposition of nanomaterials to introduce antibacterial functionalities into cotton fabrics under mild conditions. Similar to the way in which many naturally occurring biominerals evolve around the living organism under ambient conditions, this technique enables flexible substrates like the cotton fabric to be coated with inorganic-based functional materials. Specifically, our strategy involves the use of long-chain polyamines known to be responsible in certain biomineralization processes, to nucleate, organize, and deposit nanostructured ZnO on cotton bandage in an aqueous solution under mild conditions of room temperature and neutral pH. The ZnO-coated cotton bandages as characterized by SEM, confocal micro-Raman spectroscopy, XRD, UV-DRS, and fluorescence microscopy demonstrate the importance of polyamine in generating a stable and uniform coating of spindle-shaped ZnO particles on individual threads of the fabric. As the coating process requires only mild conditions, it avoids any adverse effect on the thermal and mechanical properties of the substrate. Furthermore, the ZnO particles on cotton fabric show efficient antibacterial activity against both gram-positive and gram-negetive bacteria. Therefore, the developed polyamine mediated bioinspired coating method provides not only a facile and "green" synthesis for coating on flexible substrate but also the fabrication of antibacterial enabled materials for healthcare applications.