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Inthis work, a general strategy was proposed for fine manipulatingintrinsic growth of water-soluble salts belonging to different crystalsystems. Various hollow microsphere hierarchical architectures assembledwith hopperlike single crystal blocks of cubic KBr, orthorhombic (NH4)2SO4, or hexagonal Na2SO3have been designed and prepared via microemulsions. Intrinsicgrowth manipulations of different water-soluble salts has been successfullyachieved by preventing growth of the outside surface of each singlecrystal block via a diffusion-limit effect of the interfaces betweenthe oil phase and aqueous droplets. As a result, hopperlike singlecrystals of water-soluble salts belonging to different crystal systemswere formed. Furthermore, octahedral NaCl hopperlike single crystal,rather than their typical cubic shape, has also been fabricated bymanipulating their growth rates along different lattice directionsin combination with urea as additives. The large amount of fine manipulationof intrinsic growth of water-soluble salts will provide us with adeep understanding of crystallography of inorganic salts, as wellas facilitate design and production of water-soluble salts architectureswith corresponding shapes, according to the different requirements. [ABSTRACT FROM AUTHOR]

This paper reports the finding of an investigation of a surface molecular self-assembly strategy for molecular imprinting of polymer nanowires/nanotubes. It has been demonstrated that 2,4,6-trinitrotoluene (TNT) templates were spontaneously assembled onto aminopropyl group-modified alumina pore walls by a strong charge-transfer complexing interaction between amino groups and electron-deficient nitroaromatics, forming a novel basis of surface molecular imprinting. While an additional amount of TNT templates was further replenished into a precursor mixture, a stepwise progressive polymerization was designed toward the controllable preparation of TNT-imprinted polymer nanowire/nanotube arrays in an alumina membrane. The imprinted nanowires/nanotubes with a high density of surface-imprinted sites and regular interior sites exhibit the high capacity of binding TNT molecules, which is nearly 2.5-3.0-fold that of normal imprinted particles. Moreover, the imprinted nanotubes and nanowires have ~6- and 4-fold increase in the rate of binding TNT molecules, respectively. The combination of surface molecular assembly with nanostructures in the imprinting technique can create more effective recognition sites than the only use of porogens in traditional approaches. This novel, facile strategy reported herein can be further expected to fabricate various molecular recognition nanoarrays for sensing or analytic applications. [ABSTRACT FROM AUTHOR]

In this paper, we report a simple polypeptide-directed strategy for fabricating large spherical assembly of CaCO3 nanoparticles. Stepwise growth and assembly of a large number of nanoparticles have been observed, from the formation of an amorphous liquidlike CaCO3-polypeptide precursor, to the crystallization and stabilization of polypeptide-capped nanoparticles, and eventually, the spherical assembly of nanoparticles. The "soft" poly(aspartate)-capping layer binding on a nanoparticle surface resulted in the unusual soft nature of nanoparticle assembly, providing a reservoir of primary nanoparticles with a moderate mobility, which is the basis of a new strategy for reconstructing nanoparticle assembly into complex nanoparticle architectures. Moreover, the findings of the secondary assembly of nanoparticle microspheres and the morphology transformation of nanoparticle assembly demonstrate a flexible and controllable pathway for manipulating the shapes and structures of nanoparticle assembly. In addition, the combination of the polypeptide with a double hydrophilic block copolymer (DHBC) allows it to possibly further control the shape and complexity of the nanoparticle assembly. A clear perspective is shown here that more complex nanoparticle materials could be created by using "soft" biological proteins or peptides as a mediating template at the organic−inorganic interface. [ABSTRACT FROM AUTHOR]