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While NanoCluster Beacon (NCB) is a versatile molecular probe, it suffers from a low target-specific signal issue due to impurities. Here we show that adding a “blocker” strand to the reaction can effectively block the nonfunctional probes and enhance the target-specific signal by 14 fold at a 0.1 target/probe ratio. [ABSTRACT FROM AUTHOR]

Sparse lipid fluorination enhances the lipids' 1H signal dispersion, enables clean molecular distinction by 19F NMR, and evinces micelle insertion of proteins via fluorine-induced signal shifts. We present a minimal fluorination scheme, and illustrate the concept on di-(4-fluoro)-heptanoylphosphatidylcholine micelles and solubilised seven-helix transmembrane pSRII protein. [ABSTRACT FROM AUTHOR]

Limited tumor tissue penetration is one of the key impeding factors retarding successful in vivo exploitations of anti-angiogenic cancer therapy. Herein we report on the design of a cell penetrating peptide-decorated lipid nano-assembly which, upon systemic administration, induces significant mouse tumor growth inhibition via enhanced tumor infiltration of encapsulated anti-angiogenic siRNA. [ABSTRACT FROM AUTHOR]

RuII polyazaaromatic complexes have been studied with the aim of developing molecular tools for DNA and oligonucleotides. In this context, RuII–TAP (TAP = 1,4,5,8-tetraazaphenanthrene) complexes have been developed as specific photoreagents targeting the genetic material. The advantage of such compounds is due to the formation of photo-addition products between the Ru–TAP complex and the biomolecule, originating from a photo-induced electron transfer process that takes place between the excited Ru–TAP complex and guanine (G) bases of DNA. This photo-addition has been more recently extended to amino acids in view of applications involving peptides, such as inhibition or photocontrol of proteins. More particularly, tryptophan (Trp) and Trp-containing peptides are also able to be photo-oxidized by RuII–TAP complexes, leading to the formation of photo-addition products. This mini review focuses on recent advances in the search for RuII polyazaaromatic photo-oxidizing complexes of interest as molecular tools and photoreagents for Trp-containing peptides and proteins. Different possible future directions in this field are also discussed. [ABSTRACT FROM AUTHOR]

Imaging of toll-like receptor microarrays was achieved using scanning electrochemical microscopy with the successful integration of two ferrocene derivatives in order to enhance the background contrast. This investigation has resulted in the novel fabrication of a tuneable, multiplex, broad-spectrum bacterial sensor for the interrogation of conserved microbial stimuli. [ABSTRACT FROM AUTHOR]

Almost all applications of colloidal nanocrystals require some type of purification or surface modification process following nanocrystal growth. Nanocrystal purification – the separation of nanocrystals from undesired solution components – can perturb the surface chemistry and thereby the physical properties of colloidal nanocrystals due to changes in solvent, solute concentrations, and exposure of the nanocrystal surface to oxidation or hydrolysis. For example, nanocrystal quantum dots frequently exhibit decreased photoluminescence brightness after precipitation from the growth solvent and subsequent redissolution. Consequently, purification is an integral part of the synthetic chemistry of colloidal nanocrystals, and the effect of purification methods must be considered in order to accurately compare and predict the behavior of otherwise similar nanocrystal samples. In this Feature Article we examine established and emerging approaches to the purification of colloidal nanoparticles from a nanocrystal surface chemistry viewpoint. Purification is generally achieved by exploiting differences in properties between the impurities and the nanoparticles. Three distinct properties are typically manipulated: polarity (relative solubility), electrophoretic mobility, and size. We discuss precipitation, extraction, electrophoretic methods, and size-based methods including ultracentrifugation, ultrafiltration, diafiltration, and size-exclusion chromatography. The susceptibility of quantum dots to changes in surface chemistry, with changes in photoluminescence decay associated with surface chemical changes, extends even into the case of core/shell structures. Accordingly, the goal of a more complete description of quantum dot surface chemistry has been a driver of innovation in colloidal nanocrystal purification methods. We specifically examine the effect of purification on surface chemistry and photoluminescence in quantum dots as an example of the challenges associated with nanocrystal purification and how improved understanding can result from increasingly precise techniques, and associated surface-sensitive analytical methods. [ABSTRACT FROM AUTHOR]

A useful procedure for the preparation of chemically synthesized and cross-linked polydimethylsiloxane (PDMS) gels is presented, which does not require β-irradiation for cross-linking. NMR spectra of high quality are obtained, such that even mixtures of compounds exhibiting similar NMR spectra like interconverting stereoisomers can be investigated in the residual dipolar coupling (RDC) approach of organic structure determination. [ABSTRACT FROM AUTHOR]

Cu2SnS3 (CTS) nanorods were synthesized with a controllable aspect ratio via a facile phosphine-free colloidal synthesis. This synthesis can be readily extended to obtain Cu2ZnSnS4 (CZTS) nanorods with tunable Zn content. [ABSTRACT FROM AUTHOR]

Sulfolipid-1, a tetra-acylated sulfotrehalose from Mycobacterium tuberculosis, was isolated over 40 years ago. Being a main component of the mycomembrane of M. tuberculosis, its biosynthesis and function have been studied in depth, but the chemical synthesis of sulfolipid-1 has not been reported. The synthesis presented here is based on iterative catalytic asymmetric conjugate additions of methylmagnesium bromide for the preparation of the phthioceranic and hydroxyphthioceranic acid side chains, a double regioselective reductive ring-opening and a fivefold deprotection in the final step. [ABSTRACT FROM AUTHOR]

We report a serendipitous discovery of light-induced generation of a circular microstructure on a glass surface. The microstructure has a ring shape with notable photophysical properties such as highly bright luminescence and strong resistance to photobleaching. We investigated the formation process as well as the luminescence properties of the micro ring to understand the origin of this peculiar phenomenon. [ABSTRACT FROM AUTHOR]

Liposomal nucleic acid delivery is a preferred option for therapeutic settings. The cellular pattern recognition molecule DMBT1, secreted at high levels in various diseases, and synthetic mimics efficiently inhibit liposomal nucleic acid delivery to human cells. These findings may have relevance for therapeutic nucleic acid delivery strategies. [ABSTRACT FROM AUTHOR]

Electrospray (ESI) and cryospray mass spectrometry (CSI-MS) are proving to be exceptionally versatile tools when used in conjunction with high resolution time-of-flight (TOF) systems to investigate the self-assembly of supramolecular architectures, inorganic coordination and organometallic compounds, labile molecules and clusters both from a structural and mechanistic point of view. In this feature article, we review very recent progress where mass spectrometry is being applied to highly labile and complex coordination and polyoxometalate (POM) cluster systems and we present some highlights from our initial electrospray and cryospray studies, which probe the self-assembly of inorganic cluster architectures. We discuss the major contributions of ESI and CSI-MS to labile and self-assembling inorganic architectures with great emphasis on future potential and ramifications for inorganic chemistry and the area of self-assembly as a whole. [ABSTRACT FROM AUTHOR]

The diffraction limit, dλ/2, constrains the resolution with which structures may be produced using photolithography. Practical limits for dare in the 100 nm range. To circumvent this limit, photolithography can be used to fabricate a sacrificial electrode that is then used to initiate and propagate the growth by electrodeposition of a nanowire. We have described a version of this strategy in which the sacrificial electrode delimits one edge of the nascent nanowire, and a microfabricated “ceiling” constrains its height during growth. The width of the nanowire is determined by the electrochemical deposition parameters (deposition time, applied potential, and solution composition). Using this method, called lithographically patterned nanowire electrodeposition (LPNE), nanowires with minimum dimensions of 11 nm (w) × 5 nm (h) have been obtained. The lengths of these nanowires can be wafer-scale. LPNE has been used to synthesize nanowires composed of bismuth, gold, silver, palladium, platinum, and lead telluride. [ABSTRACT FROM AUTHOR]

We report the total chemical synthesis of human C3a by one-pot native chemical ligation of three unprotected peptide segments, followed by efficient in vitro folding that yielded the anaphylatoxin C3a in high yield and excellent purity. Synthetic C3a was fully active and its crystal structure at 2.1 Å resolution showed 3 helices and a C-terminal turn motif. [ABSTRACT FROM AUTHOR]

A straightforward synthesis of comb-polypeptides of repeated peptide sequences was developed. These polypeptides were obtained by ROP of defined NCA without any post-polymerization grafting. The key to this strategy relies on the preparation of pure NCA bearing a peptide sequence on its side chain, by an original solid supported methodology. [ABSTRACT FROM AUTHOR]

A disiloxane-functionalized ionic liquid based on a phosphonium cation and a bis(trifluoromethylsulfonyl)imide (TFSI) anion was synthesized and characterized. This new ionic liquid electrolyte showed good stability with a lithium transition metal oxide cathode and a graphite anode in lithium ion cells. [ABSTRACT FROM AUTHOR]

PEGylated dendron coils (PDCs) were investigated as a novel potential nanocarrier platform. PDCs self-assembled into micelles at lower CMCs than linear copolymer counterparts by 1–2 orders of magnitude, due to the unique architecture of dendrons. MD simulations also supported thermodynamically favourable self-assembly mediated by dendrons. [ABSTRACT FROM AUTHOR]

An amphiphilic low-molecular-weight hydrogelator 1was synthesized. A tris-glycine-SDS solution gel of 1was applied for electrophoresis to separate proteins. Centrifugation of a mixture of protein and a hydrogel of 1enabled the recovery of protein. Various combinations of proteins were applied for supramolecular gel electrophoresis (SUGE), and remarkably poor mobility for small proteins (<45 kDa) was found. [ABSTRACT FROM AUTHOR]

A fluorophore labeled oligonucleotide could induce aggregation of a positively charged perylene probe. The perylene aggregate could very efficiently quench the fluorescence of the labeled fluorophore. Based on this observation, a new method for the highly sensitive and selective detection of a protein has been developed. [ABSTRACT FROM AUTHOR]

A novel fluorescence protocol, i.e., FRET/SIMNSEF, has been introduced for the first time for the sensing of mercury ions, which allows highly sensitive detection in contrast with some other approaches. [ABSTRACT FROM AUTHOR]

Cyclopenicillone (1), possessing a unique 2,5-dimethylcyclopent-2-enone carbon skeleton, has been isolated from the cultures broth of the fungus Penicillium decumbens. The structure and absolute configuration of 1were elucidated using a combination of NMR spectroscopy, CD data and computational approaches. Cyclopenicillone (1) demonstrated a dose-dependent (10–100 μM) inhibition against LPS-induced NO production in RAW264.7 macrophages. [ABSTRACT FROM AUTHOR]

By employing a click reaction, a novel method was developed for the sensitive detection of inorganic azides at as low as 21 ppb. [ABSTRACT FROM AUTHOR]

Crystals of graphite nanosheets, achieved viaa simple ball milling approach, show a significant size effect in electrocatalytic activation of oxygen. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) sheet is used as a novel substrate for dip-pen nanolithography (DPN). After GO is transferred onto SiO2using the Langmuir–Blodgett technique, CoCl2is patterned on both GO and exposed SiO2substrates simultaneously by DPN, which is used for growth of different structured carbon nanotubes. [ABSTRACT FROM AUTHOR]

A platform protocol developed based on the hollow manganese oxide nanoparticles provided multimodal diagnostic agents, which allow the selectively detect vulva cancer with T1-weighted in vivoMRI. [ABSTRACT FROM AUTHOR]

In this work, we have successfully synthesised ZnO crystal thin film with a high quality from hydrothermal reaction on sapphire substrate. The growth mechanism is clarified based on an extensive XTEM study. In addition, electrical and optical properties of the crystal thin film, which can be controlled by impurities, are characterized. The synthesis technique provides fairly high quality and cost-effective substrates for optoelectronic and renewable energy applications. [ABSTRACT FROM AUTHOR]

A sensitive aptasensor for detection of l-histidine based on the switching structure of aptamer and gold nanoparticles–graphene nanosheets (GNPs–GNSs) composite was reported for the first time. The fabricated biosensor shows an expanded linear range, excellent sensitivity and selectivity against other amino acids. [ABSTRACT FROM AUTHOR]

A polymeric composite containing a 2-aminoimidazole derivative was synthesized. It was found that this polymer was resistant to biofilm colonization by Acinetobacter baumannii, no leaching of the 2-aminoimidazole derivative was observed after 2 weeks of treatment with deionized water, and the resulting polymer was not hemolytic. [ABSTRACT FROM AUTHOR]

We have constructed a novel class of light-activatable caged molecular beacons (cMBs) that are caged by locking two stems with a photo-labile biomolecular interaction or covalent bond. With the cMBs, the nucleic acid hybridization process can be easily controlled with light, which offers the possibility for a high spatiotemporal resolution study of intracellular mRNAs. [ABSTRACT FROM AUTHOR]

Bridging microbes and electrode to facilitate the extracellular electron transfer (EET) is crucial for bio-electrochemical systems (BESs). Here, a significant enhancement of the EET process was achieved by biomimetically fabricating a network structure of graphene oxide nanoribbons (GONRs) on the electrode. This strategy is universal to enhance the adaptability of GONRs at the bio-nano interface to develop new bioelectronic devices. [ABSTRACT FROM AUTHOR]

Symmetric oligothiophene derivatives containing hydrogen bond forming segments create self-supporting organogels consisting of self-assembled 1D nanostructures at low concentrations. Hydrogen bond formation and π–π stacking were both found to be crucial for the formation of conductive supramolecular networks of 1D nanostructures. [ABSTRACT FROM AUTHOR]

The translocation time of poly(dT)45through an α-hemolysin pore was reduced in the presence of a DNA-binding Fab fragment. The Fab acts as a rudder to steer the DNA into the pore. [ABSTRACT FROM AUTHOR]

A bi-photosensitizer molecular beacon (bi-PS MB) is assembled by coupling two PS molecules, respectively, onto the opposite ends of a single MB. The MB can be triggered by a tumor marker-survivin mRNA. Fluorescence and cytotoxic 1O2generation occur effectively in breast cancer cells, but not in normal cells. Compared with a single-PS MB, a bi-PS MB exhibits much-enhanced properties in the signal-to-background ratio and 1O2generation simultaneously. [ABSTRACT FROM AUTHOR]

Highly ordered mesoporous NiFe2O4with excellent microwave absorption properties has been synthesized by using mesoporous silica (KIT-6) as a hard template. [ABSTRACT FROM AUTHOR]

The immune-response of macrophages is an important area of investigation since it represents the major pathway by which early-stage defense barriers are established in skin, lungs, and mucosal systems to counteract foreign objects. In this study, we have examined the size-dependent inflammatory and toxicological effects of nanostructured silver particles (nano-Ag) on macrophage immune cells. [ABSTRACT FROM AUTHOR]

We show evidence of the manifestation of enormous metal–insulator switching ranging up to almost six orders of magnitude in individual nanowires of β′-CuxV2O5. The magnitude and temperature of the phase transition is in strong contrast to data reported over several decades for other Wadsley-type mixed valence tunnel bronze structures. [ABSTRACT FROM AUTHOR]

A pellet-type nanomaterial prepared from a mesoporous silica-immobilized naphthalimide–DPA–Cu(ii) complex (MSIND–Cu) is investigated as a selective fluorescent chemosensor for PPi detection with a large “off–on” fluorescence change, low detection limit, short response time and a broad pH test range. [ABSTRACT FROM AUTHOR]

We demonstrate the first white light-emitting device originating from single carbon dot components. A maximum external quantum efficiency of 0.083% at a current density of 5 mA cm−2with a color-rendering index of 82 is realized, indicating that carbon dots have great potential to be an alternative phosphor for fabricating white light electroluminescent devices. [ABSTRACT FROM AUTHOR]

Mapping the transition of Ag nanotriangle to nanohole arrays revealed that the optimal SERS response was obtained near the transition. Correlated AFM and Raman imaging provided novel experimental proof that hot spots are located on Ag islands for nanotriangle arrays and in the core area of the hole for nanohole arrays, which is in agreement with previous theoretical predictions. [ABSTRACT FROM AUTHOR]

A new [2+2] tetra-hydrazone macrocyclic receptor was significantly amplified in a dynamic combinatorial library upon templation with alkaline earth metal ions. After optimisation the product could be isolated in 95% yield and its interaction with ions was investigated by NMR and UV-Vis spectroscopy. [ABSTRACT FROM AUTHOR]

A simple synthesis of Rh–Fe3O4heterodimer nanocrystals was achieved by controlled one-pot thermolysis. The nanocrystals exhibited excellent activities for the selective reduction of nitroarenes and alkenes. Furthermore the nanocrystal catalyst could be easily separated by a magnet, and recycled eight times without losing the catalytic activity. [ABSTRACT FROM AUTHOR]

One stone, two birds:Here, we have developed a simple and efficient method for the incorporation of multiple unnatural amino acids in a single protein. This single protein exhibited two different novel functionalities acquired from the genetically incorporated unnatural amino acids, which is an interesting and not an inherent property of the protein. [ABSTRACT FROM AUTHOR]

Through the esterification of an acyl chloride functionalized fullerene precursor with dendritic alcohol, a fullerene-rich dendron containing a norbornene unit at the focal point is prepared for ring-opening metathesis polymerization to obtain its linear polymer with a unimodal and narrow molar mass distribution (PDI = 1.08) by a progressive addition of catalysts. [ABSTRACT FROM AUTHOR]

To overcome shortcomings of the ex situapproaches, in situdetection using H2O2molecules to diagnose ischemia through enhanced protein direct electron transfer on a unique horseradish peroxidase–Au nanoparticles–polyaniline nanowires biofilm is demonstrated and it is discovered that the extracellular H2O2molecule released per ischemic cell is 2.7-times of that of a normal cell. [ABSTRACT FROM AUTHOR]

Formation of a chiral mesostructured porphyrin–silica hybrid with cylindrical helical stacking of anionic porphyrins was achieved by the aid of cationic organosilane. The enantiopurity of the hybrid was dramatically enhanced by a small amount of (R)-1,1′-bi-2-naphthol or its enantiomer. [ABSTRACT FROM AUTHOR]

Here, we report a simple fluorescent strip sensor based on aptamer–quantum dots technology that can meet toxin monitoring demands using ochratoxin A (OTA) as a model toxin. The limit of the detection (LOD) for the fluorescent strip was 1.9 ng mL−1, while the time needed for the detection is only 10 min; this conforms to the standards of World Health Organization (WHO) or better. Overall functional parameters are also better than the analogous characteristics of gold nanoparticle strips.High selectivity was maintained as well, making them suitable for the samples with complex solution composition. [ABSTRACT FROM AUTHOR]

A series of oligo(quinoxalineethylene)s which exhibit n-type semi-conducting features were synthesized, and adding Ag+to their solutions induced the backbones to adopt coplanar conformations due to Ag+–N coordination. [ABSTRACT FROM AUTHOR]