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Abstract: In this paper, we present a novel strategy, named Synchronous One-Pot (SOP) synthesis, to prepare gold nanoparticles (AuNPs) with a diameter of 2nm incorporated in self-assembled organic spheres with a diameter around 60nm (denoted as NPAs). Merits of this method include: (1) self-assembly of the organic component (calix[6]biscrown TAC) into spheres and the reduction of chloroauric acid (HAuCl4) take place simultaneously; (2) preparation combining UV irradiation and formaldehyde addition reduces the size and homogenizes the distribution of the resultant AuNPs within the TAC spheres. (3) Obtained material NPA gives attractive catalytic property to hydrogenation reaction. [Copyright &y& Elsevier]

Abstract: The well-known coil-to-globule transition of poly(N-isopropyl acrylamide) (PNIPAM) at its LCST lasts as short as hundred of seconds with fully reversibility. However, for the PNIPAM-containing block copolymers, thermal transformation from micelles to vesicles caused by the conformation transition of PNIPAM took as long as several weeks, even at the temperatures much higher than the LCST, and without satisfactory reversibility. In the literature, this slow process has been attributed to the strong interchain hydrogen bonding in PNIPAM, which retards the transition. In this work, asymmetrically modified PNIPAM (Mw 10K), i.e. C12-PNIPAM-CA with a hydrophobic hydrocarbon chain –C12H25 (C 12) at one end and a hydrophilic carboxyl group –COOH (CA) at the other, was prepared and found to form micelles with a core of the lightly associated hydrocarbon chains. When temperature is increased to the LCST of PNIPAM, the transformation from micelles to vesicles can be realized within 30 min, while the reverse process only takes a few minutes. Based on full monitoring of the transition process, it is proposed that the micelles serve as building blocks in constructing the vesicles via processes of combination, fusion, and etc., in which only local conformation adjustment of PNIPAM is involved. Therefore, reducing the restriction to the conformation change of PNIPAM chains, which is imposed by the micellar core, is one of the key factors in realizing the fast transition. [Copyright &y& Elsevier]

Summary of main observation and conclusion: In recent years, synthesis of hybrid heteroarm star polymer with precisely defined arms has evolved to be one of the most attractive topics within polymer chemistry. In this study, we present the successful synthesis of metallacycle‐linked heteroarm star polymers (HASPs) composed of crystalline poly(ε‐caprolactone) (PCL) and polyacrylate (poly (N‐isopropylacrylamide) (PNIPAM) segments via combination of ring‐opening polymerization (ROP) and reversible addition‐fragmentation chain transfer (RAFT) controlled radical polymerization. Firstly, a hexagonal metallacycle containing three hydroxy groups and three chain transfer agent moieties at the alternative vertexes was designed and synthesized based on the general principle of coordination‐driven self‐assembly. Subsequently, upon combination of two orthogonal post‐assembly polymerizations, a new family of HASPs containing a well‐defined hexagonal metallacycle with precisely controlled position of polymer arms was facilely prepared. Interestingly, the obtained HASPs could spontaneously self‐assemble into large‐area and regular cubic nanoparticles in tetrahydrofuran (THF)/methanol (MeOH) mixed solvents under specific conditions as confirmed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). This study provides a simple route to the controllable preparation of HASPs, and opens up a new way for further study on self‐assembly of different HASPs systems. [ABSTRACT FROM AUTHOR]

In nature, proteins self-assemble into various structures with different dimensions. To construct these nanostructures in laboratories, normally proteins with different symmetries are selected. However, most of these approaches are engineering-intensive and highly dependent on the accuracy of the protein design. Herein, we report that a simple native protein LecA assembles into one-dimensional nanoribbons and nanowires, two-dimensional nanosheets, and three-dimensional layered structures controlled mainly by small-molecule assembly-inducing ligands RnG ( n=1, 2, 3, 4, 5) with varying numbers of ethylene oxide repeating units. To understand the formation mechanism of the different morphologies controlled by the small-molecule structure, molecular simulations were performed from microscopic and mesoscopic view, which presented a clear relationship between the molecular structure of the ligands and the assembled patterns. These results introduce an easy strategy to control the assembly structure and dimension, which could shed light on controlled protein assembly. [ABSTRACT FROM AUTHOR]

In nature, proteins self-assemble into various structures with different dimensions. To construct these nanostructures in laboratories, normally proteins with different symmetries are selected. However, most of these approaches are engineering-intensive and highly dependent on the accuracy of the protein design. Herein, we report that a simple native protein LecA assembles into one-dimensional nanoribbons and nanowires, two-dimensional nanosheets, and three-dimensional layered structures controlled mainly by small-molecule assembly-inducing ligands RnG ( n=1, 2, 3, 4, 5) with varying numbers of ethylene oxide repeating units. To understand the formation mechanism of the different morphologies controlled by the small-molecule structure, molecular simulations were performed from microscopic and mesoscopic view, which presented a clear relationship between the molecular structure of the ligands and the assembled patterns. These results introduce an easy strategy to control the assembly structure and dimension, which could shed light on controlled protein assembly. [ABSTRACT FROM AUTHOR]

Binding behavior of carbohydrate and protein is known to be crucial to the biological roles of sugars. Recently, we notice that, even to the same lectin, some reported binding results based on glycopolymers and/or self-assembled glyco-nanoparticles are different from those obtained on small molecular level. Some of such discrepancy could be associated with the different detection methods used. In this paper, by using self-assembled nanoparticles based on brush and linear glycopolymers, this stereoisomerism effect was evaluated systematically, both in solution and on solution-solid interface by different methods. All measurements led to the same conclusion that the stereoisomer of sugars determined the binding ability of glyco-nanoparticles with different lectins. The investigation also provided evidence on the different binding modes of nanoparticles of linear polymers and brush polymers. [ABSTRACT FROM AUTHOR]

In nature, proteins are organized into highly ordered self‐assembled structures with various morphologies and dimensions. In their Communication on page 10691 ff., Y. Ma, G. Chen, and co‐workers report the fabrication of protein assemblies by using native protein LecA as a building block through sugar‐‐protein interactions and rhodamine dimerization. The morphologies and dimensions of the protein assemblies can be controlled by the length of the tether between the sugar and rhodamine. [ABSTRACT FROM AUTHOR]

Review: 219 refs. [ABSTRACT FROM AUTHOR]