Large pore volumes and highly accessible mesopore surface areas are present in highly ordered mesoporous bioactive glasses (MBGs) prepared by a block copolymer templating approach under non‐aqueous conditions. These glasses have a high bone‐forming bioactivity in vitro, as shown by immersing them in simulated body fluid (SBF) and monitoring the formation of hydroxycarbonate apatite (HCA) on the surface (see electron micrographs).

The investigation on the formation mechanism of helical structures and the synthesis of helical materials is attractive for scientists in different fields. Here we report the synthesis of helical mesoporous materials with chiral channels in the presence of achiral surfactants. More importantly, we suggest a simple and purely interfacial interaction mechanism to explain the spontaneous formation of helical mesostructures. Unlike the proposed model for the formation of helical molecular chains or surpramolecular packing based on the geometrically motivated model or the entropically driven model, the origin of the helical mesostructured materials may be attributed to a morphological transformation accompanied by a reduction in surface free energy. After the helical morphology is formed, the increase in bending energy together with the derivation from a perfect hexagonal mesostructure may limit the curvature of helices. Our model may be general and important in the designed synthesis of helical mesoporous materials.

We report the synthesis and characterization of a novel mesoporous material with a face-centered cubic (fcc) symmetry and intrinsic bimodal pores. Moreover, an icosahedral (ICO) mesostructure with both meso- and macroscale 5-fold symmetry is observed. We propose a hard-sphere packing (HSP) mechanism for the formation of mesoporous materials by assuming preformed robust surfactant/silicate composite micelles being hard spheres. In comparison to the conventional liquid crystal templating (LCT) or cooperative self-assembly (CSA) mechanism, our contribution provides an important advancement of knowledge in the study of mesostructured materials.

The synthesis of ultrasmall, well-dispersed, hollow siliceous spheres (HSSs) by using a block copolymer as the template and tetraethoxysilane as a silica source under acidic conditions is reported. After removing the surfactant core of as-synthesized, spherical, silica-coated block-copolymer micelles, HSSs with a uniform particle size of 24.7 nm, a cavity diameter of 11.7 nm, and a wall thickness of 6.5 nm are obtained. It is shown that by surface functionalization of HSSs with methyl groups during synthesis, HSSs can be further dispersed in solvents such as water or ethanol to form a stable sol. Moreover, the hollow cavities are accessible for further loading of functional components. In addition, it is demonstrated that HSSs possess superior endocytosis properties for HeLa cells compared to those of conventional mesoporous silica nanoparticles. A feasible and designable strategy for synthesizing novel well-dispersed hollow structures with ultrasmall diameters instead of conventional ordered mesostructures is provided. It is expected that HSSs may find broad applications in bionanotechnology, such as drug carriers, cell imaging, and targeted therapy.

By employing commercial poly(ethylene oxide)–poly(propylene oxide)–poly(ethylene oxide) (PEO–PPO–PEO) block copolymers as templates in near‐neutral aqueous solutions in the absence of organic cosolvents, unilamellar siliceous vesicles and nanofoams with ultrahigh pore volumes (> 3 cm3 g–1) are successfully synthesized. At controlled pH, a tubular micelle → unilamellar vesicle → nanofoam structural transformation is observed by increasing the reaction temperature. It is proposed that the siliceous vesicles are synthesized via a co‐operative block‐copolymer vesicle templating approach, while the siliceous nanofoams are obtained by the fusion of vesicles at increased ionic strength. Compared to literature methods to synthesize siliceous vesicles and foams, our method is convenient, cheap, and produces a high yield. Siliceous nanofoams synthesized by using our approach show superior bioimmobilization capacity over other porous materials for biomolecules with large molecular weight.

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A novel nanopore based digestion strategy has been developed by directly adding a macroporous material as catalyst to the conventional in-solution reaction system. Without increasing the enzyme or protein concentrations, this simple digestion approach exhibits high proteolysis efficiency and selectivity due to the in situ fast adsorption of both enzymes and proteins from bulk solution into the macropores of the catalysts, where the target substrates and enzymes are greatly concentrated and confined in the nanospace to realize a quick digestion. Based on the electrostatic interaction matching between the biomolecules and catalysts, selective extraction and digestion of proteins with different isoelectric points can be achieved by adjusting the surface charge of the catalysts. This nanoporous reaction system has been successfully applied to the analysis of a complex biological sample, where 293 proteins are identified, while only 100 proteins are obtained by the standard overnight in-solution digestion. The present nanospace confined digestion strategy will lead to promising advances not only in proteomics but also in other applications where enzymatic reactions are involved.

An Aggregate Signature based Trust Routing (ASTR) scheme is proposed to guarantee safe data collection in WSNs. In ASTR scheme, firstly, the aggregate signature approach is used to aggregate data and keep data integrity. What is more important, a light aggregate signature based detour routing scheme is proposed to send abstract information which includes the data sending time and ID of data, nodes' ID to the sink over different paths which can verify whether the data reaches the sink safely. In addition, the trust of a path is evaluated according to the success rate of the path. The trust of paths susceptible to frequent attack will be lowered and the path with high trust will be selected for data routing to avoid data gathering through low trust path and thereby increase the success rate of data gathering. Our comprehensive performance analysis has shown that, the ASTR scheme is able to effectively ensure an increase in success rate of data transmission by 23.23%, reduce the data amount loaded by the node by 53.59%, reduce the redundant data by 41.70%.