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The systematic combination of well-defined coordination spheres and multiple types of ligands (heteroleptic) can lead to the generation of hierarchical metallosupramolecules with a high level of complexity and functionality. In particular, a specific multilevel coordination-driven assembly through the initiate generation of multinuclear clusters can form unique heteroleptic multiple-stranded supramolecular complexes. Herein, we report novel triple-stranded nickel-based supramolecules constructed from two different ditopic ligands ([1,1':3',1''-terphenyl]-4,4''-dicarboxylate (TP) and 2,6-pyridinedicarboxylate (PDA)) and a nickel precursor. The solid-state structures of the as-synthesized supramolecules revealed that three PDA ligands are employed to fabricate a tetranuclear ({Ni

Objective : To perform a comparative analysis of therapeutic effects associated with two different shapes of ceria nanoparticles, ceria nanorods (Ceria NRs) and ceria nanospheres (Ceria NSs), in an in vitro model of traumatic brain injury (TBI).Methods : In vitro TBI was induced using six-well confluent plates by manually scratching with a sterile pipette tip in a 6×6-square grid. The cells were then incubated and classified into cells with scratch injury without nanoparticles and cells with scratch injury, which were treated separately with 1.16 mM of Ceria NSs and Ceria NRs. Antioxidant activities and anti-inflammatory effects were analyzed.Results : Ceria NRs and Ceria NSs significantly reduced the level of reactive oxygen species compared with the control group of SH-SY5Y cells treated with Dulbecco’s phosphate-buffered saline. The mRNA expression of superoxide dismutases was also reduced in nanoparticle-treated SH-SY5Y cells, but apparently the degree of mRNA expression decrease was not dependent on the nanoparticle shape. Exposure to ceria nanoparticles also decreased the cyclooxygenase-2 expression, especially prominent in Ceria NR-treated group than that in Ceria NS-treated group.Conclusion : Ceria nanoparticles exhibit antioxidant and anti-inflammatory effects in TBI models in vitro. Ceria NRs had better antiinflammatory effect than Ceria NSs, but showed similar antioxidant activity.

The fabrication of hollow mesoporous nanosilica with well-defined structural features for optimizing the integration of functional components is a challenge. Herein, we report a facile preparation of hollow fibrous nanosilica (HFNS) with high specific surface area (666 m

Co-based MOFs are directly grown using an electrodeposited layer of Co(OH)2 on carbon paper and converted to cobalt sulfide (CoxSy) through a post-treatment process. The final electrode system exhibits remarkable oxygen evolution reaction performance.

The assembly of functional nanoparticles within materials with unique architectures can improve the interfacial surfaces, defects, and active sites, which are key factors for the designing novel nanocatalysts. Nano metal–organic framework (NMOF) can be employed to fabricate nanodots-confined nanohybrids for use in electrocatalytic processes. Herein, we report a controlled synthesis of gold nanodot assembly within cobalt chalcogenide nanoshell (dots-in-shell Au/CoxSy nanohybrids). A cobalt-based NMOF (the cobalt-based zeolite imidazole framework, ZIF-67) is used as a versatile sacrificial template to yield dots-in-shell Au/CoxSy nanohybrids. Due to the synergistic effect of the well-dispersed Au nanodots and the thin CoxSy nanoshell, the obtained dots-in-shell Au/CoxSy nanohybrids exhibit enhanced performance for the oxygen evolution reaction (OER) with low overpotential values at a current density of 10 mA cm−2 and a small Tafel slope (343 mV and 62 mV dec−1, respectively).

Hybrid nanoparticles with unique tailored morphologies and compositions can be utilized for numerous applications owing to their combination of inherent properties as well as the structural and supportive functions of...

The association between boule (BOLL) and endothelin receptor type A (BEDNRA) loci and intracranial aneurysm (IA) formation has been reported via genome-wide association studies (GWASs). We sought to identify genome-wide interactions involving BOLL and BEDNRA loci for IA in a Korean adult cohort.Genome-wide pairwise interaction analyses of BOLL and BEDNRA involving 250 patients with IA and 296 controls were performed using the additive effect model after adjusting for confounding factors.Among 512,575 single-nucleotide polymorphisms (SNPs), 23 and 11 common SNPs suggested a genome-wide interaction threshold (p1.25×10-8) involving rs700651 (BOLL) and rs6841581 (BEDNRA). Rather than singe SNP effect of BOLL or BEDNRA on IA development, they showed a synergistic effect on IA formation via multifactorial pair-wise interactions. The rs1105980 of PTCH1 gene showed the most significant interaction with rs700651 (natural log-transformed odds ratio, lnOR = 1.53, p = 6.41×10-11). The rs74585958 of RYK gene interacted strongly with rs6841581 (lnOR = -19.91, p = 1.64×10-9). Although, there was no direct interaction between BOLL and BEDNRA variants, two BEDNRA-interacting gene variants of TNIK (rs11925024 and rs1231) and FTO (rs9302654), and one BOLL-interacting METTL4 gene variant (rs549315) exhibited marginal interaction with BOLL gene.BOLL or BEDNRA may have a synergistic effect on IA formation via multifactorial pair-wise interactions.

The catalytic performance and therapeutic effect of nanoparticles varies with shape. Here, we investigated and compared the therapeutic outcomes of ceria nanospheres (Ceria NSs) and ceria nanorods (Ceria NRs) in an in vivo study of mild traumatic brain injury (mTBI). In vivo TBI was induced in a mouse model of open head injury using a stereotaxic impactor. Outcomes including cytoprotective effects, cognitive function, and cerebral edema were investigated after retro-orbital injection of 11.6 mM of ceria nanoparticles. Ceria nanoparticles significantly reduced fluoro-jade B (FJB)-positive cells and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL)-positive cells, and restored mRNA levels of superoxide dismutase 1 (SOD1) and SOD2. They also decreased the cyclooxygenase-2 (COX-2) expression compared with the untreated control group. Comparing the two nanomaterials, Ceria NRs showed less stable and high-energy (100) and (110) planes, which increased the number of active sites. The Ce3+/Ce4+ molar ratio of Ceria NRs (0.40) was greater than that of Ceria NSs (0.27). Ceria NRs (0.059 ± 0.021) appeared to exhibit better anti-inflammatory effect than Ceria NSs (0.133 ± 0.024), but the effect was statistically insignificant (p = 0.190). Ceria nanoparticles also improved cognitive impairment following mTBI compared with the control group, but the effect did not differ significantly according to the nanoshape. However, Ceria NRs (70.1 ± 0.5%) significantly decreased brain water content compared with Ceria NSs (73.7 ± 0.4%; p = 0.0015), indicating a more effective reduction in brain edema (p = 0.0015). Compared with Ceria NSs, the Ceria NRs are more effective in alleviating cerebral edema following in vivo mTBI.

Crystalline metal–organic frameworks (MOFs) are extensively used in areas such as gas storage and small-molecule drug delivery. Although Cu-BTC (1, MOF-199, BTC: benzene-1,3,5-tricarboxylate) has versatile applications, its NO storage and release characteristics are not amenable to therapeutic usage. In this work, micro-sized Cu-BTC was prepared solvothermally and then processed by ball-milling to prepare nano-sized Cu-BTC (2). The NO storage and release properties of the micro- and nano-sized Cu-BTC MOFs were morphology dependent. Control of the hydration degree and morphology of the NO delivery vehicle improved the NO release characteristics significantly. In particular, the nano-sized NO-loaded Cu-BTC (NO⊂nano-Cu-BTC, 4) released NO at 1.81 µmol·mg−1 in 1.2 h in PBS, which meets the requirements for clinical usage. The solid-state structural formula of NO⊂Cu-BTC was successfully determined to be [CuC6H2O5]·(NO)0.167 through single-crystal X-ray diffraction, suggesting no structural changes in Cu-BTC upon the intercalation of 0.167 equivalents of NO within the pores of Cu-BTC after NO loading. The structure of Cu-BTC was also stably maintained after NO release. NO⊂Cu-BTC exhibited significant antibacterial activity against six bacterial strains, including Gram-negative and positive bacteria. NO⊂Cu-BTC could be utilized as a hybrid NO donor to explore the synergistic effects of the known antibacterial properties of Cu-BTC.

The oxidative addition of a silicon-chloride (Si-Cl) bond to a metal center can be a key reaction step in coordinative silicon chemistry, but this reaction is seldom observed. Herein, we report direct oxidative addition of the Si-Cl bonds of dimethyldichlorosilane (Me

Numerous attempts have been made to prepare electrocatalytic nanomaterials and construct electrode systems for effective water-splitting reactions. The growth of transition metal-based heterostruct...

Integration of two metal constituents into core–shell structures is an efficient strategy to prepare advanced materials for a variety of applications. The controllable synthesis of targeted bimetallic core–shell nanostructures is an important yet challenging task. Herein, bimetallic nanoparticles comprising a gold multipod nanoparticle (GMN) core and distinctive Pd shell (GMN@Pd NPs) are successfully synthesized in a facile and controllable manner. Epitaxial or islanded growth of Pd on the GMNs can be readily achieved using appropriate stabilizing agents. The controllable growth mode of the Pd layers, coupled with the unique topologies of GMNs, are advantageous for enhancing the density of active interfacial surfaces in the composites. Particularly, I-GMN@Pd NPs show substantially enhanced ORR activity compared with monometallic counterparts and excellent durability and better tolerance to the crossover effect than that of Pt/C, rendering the materials highly desirable for practical use.

Advanced hybrid nanomaterials (nanohybrids) with unique tailored morphologies and compositions have been used for the target-oriented catalysts due to the structural or supportive properties of each moiety and the synergistic properties of the individual components. The rational design and development of nanohybrids by integrating highly porous silica into a nano metal-organic framework (NMOF) are expected to enable unique nanospace engineering in the resulting systems to optimize their utility in the target areas. Herein, we report the design and fabrication of advanced nanohybrids composed of dendritic fibrous nanosilica (DFNS) and DFNS/gold (DFNS/Au) hybrids as the core and zinc-based NMOF (Zn-NMOF) as the shell (DFNS@Zn-NMOF) through a solution-based approach. The combined fibrous morphology of DFNS and micropores of NMOF can be directly employed for nanospace engineering in the resulting multi-compositional and hierarchical systems in a controllable manner. The DFNS/Au dots@Zn-NMOF nanohybrid shows improved catalytic performance in the Knoevenagel condensation reaction, attributed mainly to the cooperative effect stemming from the suitably organized configurations of each component.

Oxygen evolution reaction (OER) is considered a major challenge in the production of efficient electrochemical water splitting devices. To overcome the challenge, the development of inexpensive electrochemical catalysts with high energy conversion efficiencies is vital. Nanohybrids composed of noble metal nanoparticles and transition metal hydroxides often possess catalytically active sites that are beneficial for OER performance. In this study, we report a successful synthesis of Ni(OH)2 nanoflowers with a high degree of crystallinity and uniformity. The as-prepared Ni(OH)2 nanoflowers are employed as templates for effective and controllable loading of Au nanodots to obtain Ni(OH)2@Au nanohybrids. An examination of the OER activity reveals that Ni(OH)2@Au nanohybrids exhibit a considerably lower overpotential (η) value (390 mV) at a current density of 5 mA cm–2 and a smaller Tafel slope (120 mV dec–1) than those of Ni(OH)2 nanoflowers (540 mV and 324 mV dec–1, respectively). The OER enhancement effect is mainly attributed to the decoration of Au nanodots, inducing charge transfer from Ni to Au and thereby stabilizing the Ni species at high oxidation levels. Moreover, the uniform loading of Au nanodots on the anisotropic Ni(OH)2 nanoflowers provides more active interfacial surfaces, which are expedient to OER.

The effective incorporation of well-defined coordination spheres, multiple types of ligands (heteroleptic), and specific assembly modes in a given structure enables the fabrication of simplified coordinative supramolecular bio-mimics. Herein, we report the fabrication of a unique racemic macrocycle via association of metallosupramolecular helicates. A nickel ({Ni4}) cluster-based supramolecular helicate, [Ni8(PDA)6(CDBA)3(DMF)2(H2O)4] (1) (PDA = 2,6-pyridinedicarboxylate, CDBA = 4,4′-carbonyldibenzoate, DMF = dimethylformamide), is successfully synthesized and fully characterized. Dimerization of right (P-) and left (M-) handed helicates of 1via the coordination of metalloligands, [Ni(PDA2)]2− affords {[Ni8(PDA)6(CDBA)3(DMF)4–Ni(PDA)2]2} (2), which can be a representative model of the coordinative helix–helix association of heteroleptic helicates. The solid-state structures of 1 and 2 show high and selective CO2 uptake properties.

Association of boule (BOLL) and endothelin receptor type A (EDNRA) loci with intracranial aneurysm (IA) formation has been reported via genome-wide association studies. However, the underlying genome-wide interactions have yet to be reported. We sought to identify genome-wide interactions involving BOLL and EDNRA loci for IA. Genome-wide interaction analyses of BOLL and EDNRA involving 250 IA patients and 296 controls were performed under an additive effect model. Subsequent gene expression analyses were conducted using transcripts per million (TPM). A total of 23 and 11 SNPs suggested a genome-wide threshold (p < 1.25×10−8) interacting with rs700651 (BOLL) and rs6841581 (EDNRA), respectively. The rs1105980 (PTCH1) showed the most significant interaction with rs700651 (p = 6.41×10−11). The rs74585958 (RYK) interacted strongly with rs6841581 (p = 1.64×10−9). The BOLL-interacting CXCR4 was highly overexpressed in whole blood (TPM = 419.8) and CCDC3 was overexpressed in all artery-related tissues (TPM = 315.4 to 473.9). EDNRA-interacting EIF4H showed a comprehensively elevated expression across all tissues and cells (TPM = 85.8 to 372.0). Genome-wide interaction study shows that BOLL and EDNRA may contribute to IA formation by interacting with multiple genes in cardio-metabolic pathway. Our findings may provide insight into the functional relevant to IA susceptibility.

Despite recent advances toward understanding metallosupramolecular platforms, structural classification remains a challenge because of the high multiplicity and diversity originating from the variety of three-dimensional binding modes of metal ions and multifunctional ligands. In this review, multilevel coordination-driven assembly and its potential implementation in the analysis of a variety of structurally complicated metallosupramolecules are demonstrated. The classification of coordination-driven structures with their respective hierarchy levels is summarized based on the ability of each structural unit to construct ordered molecular platforms. Multilevel assembly is composed of (i) primary, (ii) secondary, (iii) tertiary, or higher-order assembly. The coordination-driven binding modes should differ by levels in a complex. In particular, tertiary assembly involves the use of predefined, well-organized secondary supramolecules as basic modules to build discrete or polymeric structures. Using the suggested concept, coordination-driven metallosupramolecular platforms can be readily classified depending on their respective hierarchical structures. We expect that this simple analytical approach will provide researchers with a more effective understanding of coordination-driven assembly and facilitate the design of new complexes for specialized applications.

Inorganic hybrid materials with anisotropic noble-metal nanoparticle cores and cagelike transition-metal chalcogenide shells are promising candidates for a wide variety of applications. Herein, we report an effective fabrication method for gold multipod nanoparticle (GMN) core–cobalt sulfide shell (GMN@CoxSy) nanostructures. The unique cagelike morphology is successfully acquired within nanohybrids (GMN@CoxSy nanocages). The cobalt-based metal–organic frameworks can act as versatile sacrificial templates to the desired hybrid nanomaterials through solution-based etching approaches without any undesirable reshaping of GMNs, which are embedded within. Examination of the electrocatalytic oxygen evolution reaction (OER) of the prepared nanohybrids reveals that a type of GMN@CoxSy nanohybrid shows a substantially lower overpotential (η) value (345 mV) compared with those of GMNs (617 mV) and CoxSy nanomaterials (418 mV) at a current density of 10 mA cm–2. The enhanced OER performance is mainly attributed to th...

Metallosupramolecule-based polymeric platforms with high degrees of hierarchy and tailorable functionalities are of great interests because of their unique morphologies and potential applications. Herein, the controllable synthesis of a highly-ordered polymeric structure, {[M,P-Co8 (PDA)6 (HIP)3 (DMF)5 (H2 O)]3 -[Co(DMF)(H2 O)2 ]} (1) (PDA=2,6-pyridinedicarboxylate, HIP=5-hydroxyisophthalate, DMF=dimethylformamide) with unique topology is reported. The solid-state structure of 1 reveals that it is alternately and periodically assembled from racemic supramolecular monomers to form a zigzag-shaped polymeric strand. Discrete racemic supramolecules (2) with topologies similar to those of monomeric species of 1 are also controllably synthesized in a separate reaction. Formation of intermolecular hydrogen bonds between supramolecules associated with hydroxyl groups of HIPs are critical for the unique solid-state packing geometries of 1 and 2.

Coordination polymer particles (CPPs) with a high degree of porosity and multi-functional reaction sites are promising for diverse applications. The integration of open sites favorable for the post-modification of CPPs presents a unique opportunity for the rational design of inorganic materials with target-oriented functions. Herein, we report a shape-controllable synthetic protocol for zinc-based coordination polymer nanocubes (Zn-CPNs). In the synthesis, 2,6-bis[(4-carboxyanilino)carbonyl] pyridine ([N3]) ligand is employed as an efficient shape-directing modulator to control the size and shape of Zn-CPNs. More importantly, the [N3] ligand provides metal binding sites suitable for the decoration of other functional metals such as copper ions. The copper-modified Zn-CPNs (Cu_Zn-CPNs) show good activities in a heterogeneous catalytic reaction.

Morphologically unique silica nanoparticles can be used as effective templates to prepare silica–metal hybrid nanomaterials, which are highly applicable in a variety of areas. Mesoporous silica nanoparticles, which have high surface areas and an abundance of pores, can be used to synthesize mesoporous silica core–metal shell nanostructures with catalytically active sites. In this work, dendritic fibrous nanosilica (DFNS) with a high surface area is successfully employed as a template to synthesize DFNS/Au hybrid nanomaterials. Au nanodots are initially synthesized through the selective reduction of Au ions on the surface of the DFNS after surface modification to form DFNS/Au dots. A seed‐mediated growth method is used to controllably grow Au nanoparticles on the DFNS/Au dots to generate DFNS core–Au nanoparticles shell nanohybrids (DFNS/Au NPs) and DFNS core–Au layer shell nanohybrids (DFNS/Au layers). The catalytic activities of DFNS/Au NPs and DFNS/Au layers in the 4‐nitrophenol reduction reaction are compared.

A glassy carbon electrode (GCE) was successfully functionalized with amine groups ( NH2) through the electrooxidation of carbamic acid, to produce an aminated GCE. The aminated GCE could be effectively used to detect current changes during the urease-catalyzed decomposition of urea. The silk fibroin (SF) scaffolds were used to place urease near the surface of the aminated GCE (urease/SF/aminated GCE). The prepared electrode was employed for electrochemical urea sensing utilizing cyclic voltammetry and amperometry techniques. The fabricated sensing platform displayed rapid detection response and high sensitivity of 112.3 μA mM−1 cm−2 with a linear correlation between current and urea concentrations (0.3–2.7 mM). Values for limit of detection (LOD) and limit of quantification (LOQ) were estimated to be 0.163 mM and 0.394 mM, respectively. The reproducible sensing responses recorded using the urease/SF/aminated GCE comprising replaceable SF discs (generated and functionalized with urease in the same batch) assure the suitability of the present platform for application in urea sensing devices.

Advanced hybrid nanomaterials tailored with unique morphologies and multiple functions can be synthesized by the controllable integration of two or more well-designed components. The distinctively shaped metal cores with well-defined coordination polymer shells can lead to synergistic structural properties in the resultant hybrid materials. Herein, we report a facile synthetic strategy for gold multipod nanoparticle (GMN) core-zeolitic imidazolate framework (ZIF-67) shell (GMN@ZIF-67) nanohybrids. Because of the structural anisotropy, which is crucial for heterogeneous seed-induced nucleation, and uniqueness of GMNs, their combination with ZIF-67 gives characteristic core-shell materials. The synthetic process can be readily achieved without using surfactants or capping reagents. Thus, it is potentially an environmentally friendly route to expedient nanohybrids. The material properties (i.e., surface area, size, and shape) of the resultant GMN@ZIF-67 nanohybrids can be readily controlled by simply varying the relative amount of GMNs and ZIF-67 precursors used.

Metal–organic frameworks (MOFs) with compositional multiplicity show unique topologies as well as enhanced chemical and physical properties. The construction of mixed-metal frameworks containing more than one type of metal element can provide further structural versatility and diversity. The combination of transition- and alkali-metal elements in a framework can result in interesting materials with substantial advantages. Herein, we report a synthetic strategy for the mixed transition- and alkali-metal frameworks [Na2Co(PDA)2] (1, PDA = 2,6-pyridinedicarboxylate) and [K2Co(PDA)2] (2). The solid-state structures of these frameworks show that two PDA ligands chelate to a cobalt ion to form a Co(PDA)22– species, which in turn undergoes further assembly mediated by alkali-metal cations (Na+ or K+) to give mixed-metal framework structures. The {[KCo(PDA)2]–·[NH2(CH3)2]+} framework (3) is also prepared by a change in stoichiometry. The multiple coordination of alkali metal atoms to the carboxylate oxygen atoms of the PDA ligands of the Co(PDA)22– species generates unique three-dimensional architectures. As 2 and 3 react with NaOH, the coordinated K+ exchanges readily with Na+ in aqueous solution, and finally 1 crystallizes. The strong ionic character and small size of Na+ account for the facile transformations of 2 and 3. Temperature-dependent magnetization studies reveal that 1 exhibits distinct magnetic susceptibility relative to those of 2 and 3.

Nanoparticle assemblies within hollow nanoshells represent versatile structures which enable efficient nanosystems with colligative properties of nanoparticles for a variety of applications. In this report, we present a simple and high yielding solution-based synthetic strategy for peapod-shaped Au nanoparticle assembly encapsulated within hollow silica nanotubes (pp multi-Au@SiO2 NTs). One-dimensional, [multiple Au nanodot] core–[silica] shell nanowires (multi-Au@SiO2 NWs) are preferentially synthesized based on reverse microemulsion (water-in-oil) techniques. By thermal treatment of multi-Au@SiO2 NWs in aqueous polyvinylpyrrolidone (PVP) solution, pp multi-Au@SiO2 NTs can be successfully fabricated. Further growth of Pt on the Au nanoparticles in pp multi-Au@SiO2 NTs can lead to the generation of [Au] core-[Pt] shell (Au/Pt) nanoparticle assembly surrounded by silica nanotubes (pp multi-Au/Pt@SiO2 NTs).

Highly-ordered heteronanostructures can be synthesized by overgrowth of a secondary material on the as-prepared seed nanocrystal. The unique morphology of seed nanocrystals directs the shape of the secondary structure, which is exploited to develop structure-controlled composite nanomaterials. Herein, we report a facile and controllable synthetic strategy toward noble star-shaped bimetallic nanostructures. Gold multipod nanoparticle (GMN) core-platinum shell nanoparticles (GMN@Pt NPs) are successfully synthesized through the overgrowth of Pt on the surface of GMN seeds. Due to the structural uniqueness of GMNs, GMN@Pt NPs show bimetallic core-shell geometries, which have surface roughness and star-shaped multi-branches with sharp edges and tips. The island nucleation and growth of individual Pt particles to form a shell provide larger surface areas and plenty of defects on the bimetallic nanocrystals. GMN@Pt NPs with optimized Pt shells show much higher catalytic activities in 4-nitrophenol reduction and ethanol electrooxidation than those of GMNs or Pt nanoparticles, mainly due to the synergistic effects of the bicomponent nanosystem.

The synthesis of hybrid nanoparticles with multiple functions from the economical and scalable perspective is an important issue in nanoparticle engineering. Herein, we report a representative example of multi-functional nanosystems simultaneously possessing fluorescence and magnetism as well as the excellent structural properties of nanosilica. Highly fluorescent multiple Fe3O4 nanoparticles core-silica shell nanoparticles (FL multi-Fe3O4@SiO2 NPs) are successfully synthesized and fully characterized. The multiple Fe3O4 nanoparticles can be uniformly and collectively encapsulated within a silica matrix using a reverse microemulsion (RM) method. Fluorescent dyes are successfully functionalized through the sequential hydrolysis and condensation of tetraethylorthosilicate (TEOS) and 3-(aminopropyl) triethoxysilane (APTES). Both organic (fluorescein) and inorganic (Rubpy) dyes can be used to generate the FL multi-Fe3O4@SiO2 NPs. These synthetic paradigms for multi-functional nanoparticles can significantly facilitate the fabrications of unique nanomaterials widely applied in a variety of areas.

Nanosystems using a platinum (Pt) nanodots assembly (multi-Pt nanoparticles, m-Pt) as the core and silica (SiO2) shells were successfully synthesized as m-Pt@SiO2 spherical nanoparticles (NPs) and m-Pt@SiO2 nanochains (NChs) by a reverse microemulsion (water-in-oil)-based method. The kinetically controlled reduction of K2PtCl4 by the Brij35 surfactant within reverse micelles, followed by condensation of tetraethyl orthosilicate, led to the formation of multi-Pt nanodots core–silica shell systems. The reduction kinetics for the growth of core–shell systems was studied in both the presence of reducing agents such as ascorbic acid, glucose, and ethylene glycol and in the absence of supplementary agents, as well as the variation of water-to-surfactant ratio. To assemble Pt NPs within a one-dimensional SiO2 matrix, we attempted to grow Pt NPs in␣situ while the SiO2 materials grew one-dimensionally in a modified microemulsion system. By changing the pH of the reaction media or using highly concentrated ethylene glycol in the synthetic approach, we successfully synthesized m-Pt@SiO2 NChs.

Effective incorporation of multiple types of ligands in a given coordination structure provides structural complexity and functional diversity to the resultant coordination-driven assembly. One of the most widely used synthetic approaches is the utilization of the molecular symmetry principle to combine multiple ligands and specific metallic centers in a preferred manner. The variation of metal ions can be helpful to understand the importance of symmetry for the generation of structurally hierarchical supramolecular platforms. We describe the synthesis and characterization of isostructural supramolecular helicates, [M8 (PDA)6 (AIP)3 (DMF)6-x (H2 O)x ] (M=Ni (1), Co (2), and Mn (3); PDA=2,6-pyridinedicarboxylate; AIP=5-aminoisophthalate; x=0 for 1, and x=4 for 2 and 3). The effect of metal variation on the formation of supramolecular helicates and their solid-state crystal packing are discussed. Despite the disparity in the ionic radii and distinct coordination-geometry preferences of Co2+ , Ni2+ , and Mn2+ , all metal centers engaged in the assembly with the heteroleptic ligands in the same manner to form isostructural supramolecular helicates.

A cobalt (Co) supramolecular triple-stranded helicate, [Co8(PDA)6(Br-PTA)3(DMF)4(H2O)2] (1) (PDA = 2,6-pyridinedicarboxylate, Br-PTA = 5-bromoisophthalate, DMF = dimethylformamide), is successfully synthesized and fully characterized. The solid-state structure of 1 shows that four cobalt atoms are coordinated by three PDA ligands to form a tetranuclear cobalt cluster with three extension points and the ditopic Br-PTA ligands interlink two basic assembly units. In crystal packing, the bromo group is surrounded by the cavity-like tetranuclear cobalt cluster, which acts as a metallocavitand, to generate a unique cage-like crystal packing geometry. The isomorphous molecular cage, which exhibits a similar crystal-packing geometry as observed in 1, is also successfully isolated. This is an unusual example of a highly symmetric cage-like crystal packing architecture, resulting from the interaction among metallocavitands of in situ generated supramolecular modules.

The amorphous state of pharmaceuticals has attracted much attention due to its high bioavailability and other advantages. The stability of the amorphous state in relation with the local molecular mobility is important from both fundamental and practical points of view. The acoustic properties of amorphous progesterone, one of the representative steroid hormones, were investigated by using a Brillouin inelastic light scattering technique. The Brillouin spectrum of the longitudinal acoustic mode exhibited distinct changes at the glass transition and the cold-crystallization temperatures. The acoustic dispersions of the longitudinal sound velocity and the acoustic absorption coefficient were attributed to the fast and possibly the secondary relaxation processes in the glassy and supercooled liquid states, while the structural relaxation process was considered as the dominant origin for the significant acoustic damping observed even in the liquid phase. The persisting acoustic dispersion in the liquid state was attributed to the single-molecule nature of the progesterone which does not exhibit hydrogen bonds in the condensed states.

Silk fibroin (SF) is a natural polymer widely used and studied for diverse applications in the biomedical field. Recently, genetically modified silks, particularly fluorescent SF fibers, were reported to have been produced from transgenic silkworms. However, they are currently limited to textile manufacturing. To expand the use of transgenic silkworms for biomedical applications, a solution form of fluorescent SF needed to be developed. Here, we describe a novel method of preparing a fluorescent SF solution and demonstrate long-term fluorescent function up to one year after subcutaneous insertion. We also show that fluorescent SF labeled p53 antibodies clearly identify HeLa cells, indicating the applicability of fluorescent SF to cancer detection and bio-imaging. Furthermore, we demonstrate the intraoperative use of fluorescent SF in an animal model to detect a small esophageal perforation (0.5 mm). This study suggests how fluorescent SF biomaterials can be applied in biotechnology and clinical medicine.

Raspberry-like gold nanoparticles (Au RLNPs) synthesized through reduction of HAuCl4 by using Brij35 surfactant and NaOH show high catalytic activity in the reduction of 4-nitrophenol and ethanol electrooxidation. The enhanced catalytic activity of Au RLNPs is mainly due to their high surface roughness. However, Au RLNPs are easily changed to spherical or aggregated nanoparticles by treatment with acids, thiols, and cationic surfactants (e.g., CTAB), making it difficult to sustain the catalytic activity. To improve the stability and applicability in a wide range of environments without degrading the original Au RLNP morphology, silica-coated Au RLNPs (Au RLNP@SiO2 NPs) were successfully synthesized through a sol–gel process using poly(vinylpyrrolidone) (PVP) as a primer. In comparison with Au RLNPs and other Au nanoparticles, Au RLNP@SiO2 NPs are more easily recovered and recycled in repeated catalytic reactions.

Uniform nanostructured nickel-based coordination polymer particles with multilayered morphologies (mL-NiCPPs) were successfully fabricated through a two-step heating process. To increase the surface area by reducing the size of mL-NiCPPs, pyridine and acetic acid were added as size modulators during the growth process. The resultant coordination polymer nanoparticles were then calcinated at a controlled temperature in order to produce nickel oxide nanostructures (mL-NiOs), which have a regular multilayered morphology and a high degree of crystallinity. Moreover, the mL-NiOs had a relatively high BET specific surface area (112 m2 g−1) and a well-defined pore size (10 nm), hence exhibited significant potential for use in a variety of applications. The synthesized mL-NiOs were successfully deposited onto indium tin oxide (ITO) serving as an efficient matrix for the immobilization of urease (Ur), which was used for urea detection. The prepared bioelectrode (Ur/NiO/ITO/glass) was employed for urea sensing using cyclic voltammetry (CV). The prepared electrodes showed a high sensitivity and a linear dependence of the current on the urea concentration.

We report a strategy to achieve a discrete cage molecule featuring a high level of structural hierarchy through a multiple-assembly process. A cobalt (Co) supramolecular triple-stranded helicate (Co-TSH)-based discrete molecular cage (1) is successfully synthesized and fully characterized. The solid-state structure of 1 shows that it is composed of six triple-stranded helicates interconnected by four linking cobalt species. This is an unusual example of a highly symmetric cage architecture resulting from the coordination-driven assembly of metallosupramolecular modules. The molecular cage 1 shows much higher CO2 uptake properties and selectivity compared with the separate supramolecular modules (Co-TSH, complex 2) and other molecular platforms.

Multiple gold (Au) nanodots core–mesoporous silica shell nanoparticles (multi-Au@mesoporous-SiO 2 NPs) were successfully synthesized in solution through a soft-etching methodology. Thermal treatment of the multi-Au@SiO 2 NPs in water without adding any other additives lead to generation of mesopores over the silica shell without any change in the size and number of the Au nanodots. The multi-Au@mesoporous-SiO 2 NPs showed much higher catalytic activity in the reduction of 4-aminophenol than multi-Au@SiO 2 NPs and other single Au nanodot core–silica shell nanoparticles with york-shell morphologies, which were also effectively fabricated (single-Au@SiO 2 NPs and single-Au@mesoporous-SiO 2 NPs). The enhanced catalytic activity is mainly due to the efficient diffusion of reactants onto the multiple Au nanodots through mesopores within the silica shell as well as the higher surface area of multiple Au nanodots.

Nano- (or micro-scale) metal-organic frameworks (NMOFs), also known as coordination polymer particles (CPPs), have received much attention because of their structural diversities and tunable properties. Besides the direct use, NMOFs can be alternatively used as sacrificial templates/precursors for the preparation of a wide range of hybrid inorganic nanomaterials in straightforward and controllable manners. Distinct advantages of using NMOF templates are correlated to their structural and functional tailorability at molecular levels that is rarely acquired in any other conventional template/precursor. In addition, NMOF-derived inorganic nanomaterials with distinct chemical and physical properties are inferred to dramatically expand the scope of their utilization in many fields. In this review, we aim to provide readers with a comprehensive summary of recent progress in terms of synthetic approaches for the production of diverse inorganic hybrid nanostructures from as-synthesized NMOFs and their promising applications.

Gold multipod nanoparticles (Au Multipod NPs) containing multi-branches with sharp edges and tips were synthesized in high yield through a facile seed-mediated method using cetyltrimethylammonium bromide (CTAB), Brij35, Au seed nanoparticles, Ag(+) ions, ascorbic acid, and sodium salicylate. The branch lengths of Au Multipod NPs were finely controlled by adjusting the molar ratio of mixed surfactants, and in particular by changing the amount of sodium salicylate. A formation mechanism for the star-shaped topologies was proposed and experimentally proved. The catalytic activity of the synthesized Au Multipod NPs was evaluated in ethanol electrooxidation reaction. The dependence of the catalytic performances on the nanostructural morphology was investigated.

We report a rapid, simple, single-step, and high-yielding solution-phase synthesis of raspberry-like gold nanoparticles (Au RLNPs) with rich edges and high surface areas. Au RLNPs were synthesized through the reduction of HAuCl4 simply mediated by nonionic Brij surfactant in basic conditions without any other reducing agents or organic molecules. The synthesized nanoparticles possessed high surface areas and were stable in basic or neutral conditions, which are potentially useful structural factors for the applications. The unique, highly red-shifted surface plasmon resonances (SPRs) of Au RLNPS originate from their rough, raspberry-like surfaces. The sizes of Au RLNPs were controllable by varying the amounts of NaOH and HAuCl4. However, there are very few reported facile syntheses of size-controlled multi-branched gold nanoparticles simply mediated by surfactant without any other reducing agents or organic molecules.