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Intercellular Adhesion Molecule-1 (ICAM-1) is considered to be a cancer biomarker in the assessment of metastatic potential in patients and an early indicator of atherosclerosis. A labelless biosensor based on the surface plasmon resonance (SPR) signal from the specific affinity interaction of an aptamer and a soluble ICAM-1 protein was developed for blood samples. The developed aptasensor provided real-time information on the concentration of the ICAM-1 protein in blood when integrated to a purification step based on a magnetic pull-down separation. The SPR aptasensor was highly specific with a limit of detection of 1.4/0.2 ng ml

Herein, a novel long wavelength monostyryl BODIPY derivative (BDZ-1) has been synthesized by rational design and used to detect oxalyl chloride, a highly reactive and harmful chemical to humans and other living organisms, with high sensitivity and selectivity. The purple solution of BDZ-1 changed to pink color immediately upon the addition of oxalyl chloride and the weak red fluorescence changed to strong orange fluorescence simultaneously. In addition, the practicability of BDZ-1 was further explored by using a smartphone application, allowing the sensitive and selective on-site detection of oxalyl chloride.

This study, it is aimed to develop an electrochemical aptasensor that can detect phosphate ions using 3.3'5.5' tetramethylbenzidine (TMB). It is based on the principle of converting the binding affinity of the target molecule phosphate ion (PO

A new catechol-substituted monostyryl boradiazaindacene (BODIPY)-based lanthanide-free colorimetric and fluorogenic probe was developed for the sequential detection of Cu2+ ions and dipicolinic acid (DPA), a distinctive biomarker of bacterial endospores, with high sensitivity and selectivity. In the presence of Cu2+ ions, the blue solution of the probe changes to cyan and the fluorescence is quenched, however, the cyan color changes to blue immediately and the fluorescence is restored on contact with DPA, resulting from competitive binding of DPA that interact with Cu2+ ions. A practical application by using Geobacillus stearothermophilus spores was further studied and as low as 1.0 x 105 spores were detected.

Carbendazim, is a broad-spectrum fungicide and also a promising experimental antitumor drug as reproduction and developmental toxicant, which is currently under phase II preclinical trials. In this study, an approach based on controlled and targeted release with aptamers and mesoporous silica nanoparticles was investigated to improve the antitumor activity of carbendazim. To this end, we synthesized aptamer conjugated silica nanoparticles for testing cytotoxicity properties in vitro with human cervical adenocarcinoma (HeLa) cultured cells. Nucleolin (AS1411) binding aptamers were used to entrap carbendazim molecules inside nanopores of MCM-41 type silica nanoparticles to obtain a stimuli-dependent release system. The effect of carbendazim loaded aptamer silica complex was tested and compared to free carbendazim treatment on HeLa cells, demonstrating 3.3 fold increase of toxicity on targeted cells with our delivery system. In addition, cytotoxicity of the complex was determined to be mostly due to increased apoptosis and to a less extend necrosis related pathways.

Nanotechnology is an encouraging interdisciplinary arena of research in this decade, which has been widely applied in various fields, including pharmaceuticals, agriculture, cosmetics, food preservation, electronics, biosensors, and bioimaging. In a broad sense, it relies on the synthesis and modulation of nanosized materials through modifications of the properties of raw materials. A large variety of inorganic and organic nanostructures have been investigated and used for their unique physicochemical and biological properties such as morphological diversity, high surface area to volume ratio, stability, dispersity, and toxicity to microorganisms or tumor cells. Due to such remarkable properties, many other application areas are yet to be explored in addition to the current applications. Carbon is one of the most abundant elements on the earth. In recent years, various carbon-based nanoparticles such as carbon quantum dots, carbon dots, and carbon nanotubes have been developed as one of the most valuable groups of nanomaterials with diverse applications. However, drawbacks such as the use of toxic precursor chemicals, organic solvents, and generation of toxic by-products associated with conventional synthesis methods have limited the applications in biomedical areas. To overcome these problems, green synthesis of nanoparticles has been projected as sustainable and unconventional to chemical methods. Rapidity of synthesis and effective cost has been established as a substitute for physical methods. For the green synthesis of carbon nanoparticles, naturally occurring and economically viable resources have been proposed. In this study, we explore the recent advances in the development of carbon-based nanomaterials synthesized by eco-friendly and green routes and their applications in biomedical areas.

Herein, we present a study on the catalytic evaluation of biocompatible chitosan-stabilized gold nanoparticles (CH-AuNPs) on the oxidation of morin as a model reaction. Biocompatible CH-AuNPs have been characterized through several analytical methods such as TEM, UV–vis, DLS and zeta potential analyses. CH-AuNPs have a small size (10 ± 0.4 nm) with a narrow size distribution and high positive surface charge (+40.1 mV). CH-AuNPs has been demonstrated to be highly active nanocatalysts for the oxidation of morin with the assistance of H2O2 as an oxidant compared with control experiments. The oxidation reaction follows a pseudo-first-order reaction. The kinetic studies show that apparent rate constant (kapp) is positively correlated with the concentrations of CH-AuNPs and H2O2, while it is negatively correlated with morin concentration. Furthermore, the reusability tests have been performed and the results demonstrate the long-term stability and reusability of CH-AuNPs without any loss of catalytic activity. Cytotoxicity studies exhibit that CH-AuNPs have low toxicity and they are biocompatible with HeLa and MCF-7 cells.

In this study, analytical studies of Chitosan-Cobalt(II) (CTS-Co(II)) nanoparticles (CTS - Co NPs) by mimicking horseradish peroxidase (HRP) were evaluated. In the applications, it was observed that CTS-Co NPs 3,3' 5,5' tetramethylbenzidine (TMB) oxidized in the presence of hydrogen peroxide (H

A novel highly substituted and fluorescent aromatic-fused imidazole derivative has been synthesized by rational design. This novel fluorescent material acts as an alternative antibacterial agent against Gram positive bacteria strains. It shows superior antibacterial activity (with MIC value of 8 μg/mL) against methicillin-resistant Staphylococcus aureus (MRSA) when compared with standard antibiotic drugs Ampicillin (with MIC value of 128 μg/mL) and Kanamycin (with MIC value of >512 μg/mL). The interaction of this novel compound with the bacterial cell and genomic DNA has also been studied to elucidate antibacterial mode of action. Fluorescence spectroscopy and microscopy studies have proved the intracellular uptake of this special compound. Likewise, UV-vis and fluorescence spectroscopy studies have revealed a significant decrease in the absorption and emission bands of the compound upon its interaction with plasmid and genomic DNA, which is likely due to its DNA intercalation property. Furthermore, these findings have been supported by gel electrophoresis of genomic DNA of S. aureus cells treated with the compound. The results indicate that this novel compound exerts its antibacterial activity by causing DNA damage, suggesting the potential utility of fluorescent probes for real-time diagnosis and treatment of bacterial infections.

A novel ratiometric colorimetric and fluorescent dual probe based on Eriochrome Black T (EBT)-Eu3+ complex was designed to detect dipicolinic acid (DPA), a major constituent of bacterial spores, with high sensitivity and selectivity. UV-vis titration experiments demonstrated that EBT and Eu3+ ions formed a 1:1 coordination pair in water. In the presence of Eu3+ ions, the blue solution of EBT changed to magenta, however, upon the addition of DPA, the magenta color changed to blue immediately and characteristic fluorescence emission from DPA-Eu3+ complex was observed. In addition, the sensitivity of the system was further evaluated on Geobacillus stearothermophilus spores and as low as 2.5 × 105 spores were detected.

The concentration of nitrite (NO2−) ions above allowable limits in water resources and food stuffs is considered hazardous and has been proven to be of great threat to the environment and public health. In this work, an acenaphtho [1,2-d] imidazole derivative (1) as a ratiometric colorimetric probe is developed. UV–Vis experiments demonstrate that the probe 1 shows excellent selectivity toward NO2− in the presence of other potential interfering species, a rapid response (20 s) and a low detection limit (100 nM) by a distinct visual color change with a bathochromic shift of 120 nm from colorless to intense yellow. Besides, this probe is further used for the quantification of nitrite ions in environmental water resources such as tap water, underground water, and surface water samples. The high recoveries (96–99% with relative standard deviations (RSD) of

WOS: 000390182600053 PubMed: 27852519 Gold nanoparticles (GNPs) functionalized with ethylenediamine-lanthanide complexes (Eu-GNPs and Tb-GNPs) were usedfor the selective fluorescent detection of dipicolinic acid (DPA), a unique biomarker of bacterial spores, in water. Particles were characterized by transmission electron microscopy and zeta potential measurements. The coordination of DPA to the lanthanides resulted in the enhancement of the fluorescence. A selective response to DPA was observed over the nonselective binding of aromatic ligands. The ligand displacement strategy were also employed for the ratiometric fluorescent detection of DPA. 4,4,4-trifluoro-1-(2-naphthyl)-1,3-butanedion (TFNB) was chosen as an antenna to synthesize ternary complexes. The addition of DPA on EuGNP:TENB ternary complex quenched the initial emission of the complex at 615 nm and increased the TFNB emission at 450 nm when excited at 350 nm. The results demonstrated that the ratiometric fluorescent detection of DPA was achieved by ligand displacement strategy. (C) 2016 Elsevier B.V. All rights reserved. Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [114Z088] This research was financially supported by the Scientific and Technological Research Council of Turkey (TUBITAK), Project No: 114Z088 which is gratefully acknowledged here.

Herein, we report the synthesis of silver nanoparticles (AgNPs) by a green route using the aqueous leaf extract of Morus indica L. V1. The synthesized AgNPs exhibited maximum UV-Vis absorbance at 460 nm due to surface plasmon resonance. The average diameter (~54 nm) of AgNPs was measured from HR-TEM analysis. EDX spectra also supported the formation of AgNPs, and negative zeta potential value (−14 mV) suggested its stability. Moreover, a shift in the carbonyl stretching (from 1639 cm−1 to 1630 cm−1) was noted in the FT-IR spectra of leaf extract after AgNPs synthesis which confirm the role of natural products present in leaves for the conversion of silver ions to AgNPs. The four bright circular rings (111), (200), (220) and (311) observed in the selected area electron diffraction pattern are the characteristic reflections of face centered cubic crystalline silver. LC-MS/MS study revealed the presence of phytochemicals in the leaf extract which is responsible for the reduction of silver ions. MTT assay was performed to investigate the cytotoxicity of AgNPs against two human cell lines, namely HepG2 and WRL-68. The antibacterial study revealed that MIC value of the synthesized AgNPs was 80 µg/ml against Escherichia coli K12 and Staphylococcus aureus (MTCC 96). Finally, the synthesized AgNPs at 10 µg/ml dosages showed beneficial effects on the survivability, body weights of the Bombyx mori L. larvae, pupae, cocoons and shells weights via enhancing the feed efficacy.

Polyelectrolyte multilayer (PEM) films composed of two natural polysaccharides (hyaluronic acid and chitosan) were deposited through layer-by-layer (LbL) assembly on top of biocompatible mesoporous silica nanoparticles (MSNPs). Polyelectrolyte multilayer coated mesoporous silica nanoparticles (PEM-MSNPs) were characterized by using attenuated total reflection–fourier transform infrared spectroscopy (ATR–FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), nitrogen adsorption-desorption isotherms, UV–vis and fluorescence spectrophotometer. A commercially available and industrially used optical brightener, 4,4′-distyrylbiphenyl sulfonate sodium salt (CBSX) was loaded into nanocontainers (CBSX@PEM-MSNPs) to evaluate their use for the pH-sensitive release. The controlled release of CBSX from nanocontainers in response to pH is monitored by using UV–vis and fluorescence spectrophotometer in water and the almost 100% of encapsulated CBSX is released within 2 h at pH 7. The increase in both whiteness and total color change at pH 7 on a cellulose fabric demonstrates the great potential of nanocontainers as pH-sensitive whitening agents for optical bleaching of cellulose fabrics.

Since discovery of the first antibiotic drug, penicillin, in 1928, a variety of antibiotic and antimicrobial agents have been developed and used for both human therapy and industrial applications. However, excess and uncontrolled use of antibiotic agents has caused a significant growth in the number of drug resistant pathogens. Novel therapeutic approaches replacing the inefficient antibiotics are in high demand to overcome increasing microbial multidrug resistance. In the recent years, ongoing research has focused on development of nano-scale objects as efficient antimicrobial therapies. Among the various nanoparticles, silver nanoparticles have gained much attention due to their unique antimicrobial properties. However, concerns about the synthesis of these materials such as use of precursor chemicals and toxic solvents, and generation of toxic byproducts have led to a new alternative approach, green synthesis. This eco-friendly technique incorporates use of biological agents, plants or microbial agents as reducing and capping agents. Silver nanoparticles synthesized by green chemistry offer a novel and potential alternative to chemically synthesized nanoparticles. In this review, we discuss the recent advances in green synthesis of silver nanoparticles, their application as antimicrobial agents and mechanism of antimicrobial mode of action.

A novel ratiometric colorimetric and fluorescent dual probe based on Eriochrome Black T (EBT)-Eu

WOS: 000416369800026 PubMed: 29103500 A novel chitosan-based ratiometric fluorescent probe incorporating an EDTA-Eu3+ complex as the sensing unit and fluorescein dye as the internal standard was designed to detect dipicolinic acid (DPA) as an anthrax bio-marker with high sensitivity and selectivity. The fluorescence intensity of fluorescein dye attached to the chitosan backbone remains constant as an internal reference, while the Eu3+ emission increased linearly upon the consecutive addition of DPA. The selectivity studies were performed by adding different competitive aromatic ligands to the sensing environment and no signifacant fluorescence response was observed. The results demonstrated the superior selectivity of the system to DPA. Overall, this novel chitosan-based ratiometric fluorescent probe enables ratiometric and sensitive DPA detection over nanomolar concentrations (as low as 10 nM) and displays straightforward selectivity over other competitive aromatic ligands. Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [114Z088]; Konya Food and Agriculture University Strategic Products Research and Development Center (SARGEM); Nanobiz R D ltd. This research was financially supported by the Scientific and Technological Research Council of Turkey (TUBITAK), Project No: 114Z088 which is gratefully acknowledged here. The corresponding author would also like to thank Konya Food and Agriculture University Strategic Products Research and Development Center (SARGEM) and Nanobiz R & D ltd. for their support of this research.

Gating of mesoporous silica nanoparticles (MSNs) with the stimuli-responsive poly(β-amino ester) has been achieved. This hybrid nanocarrier releases doxorubicin (DOX) under acidic conditions or in the presence of porcine liver esterase. The DOX loaded poly(β-amino ester)-capped MSNs reduce cell viability when tested on MDA-MB-231 human breast cancer cells.

A novel chitosan-based ratiometric fluorescent probe incorporating an EDTA-Eu

The electrosynthesis of a low band-gap and neutral-state green linear polymer incorporating a BODIPY core as the acceptor and bis(3,4-ethylenedioxythiophene) (bis-EDOT) as the donor has been described. Resulted polymer exhibited two well-defined absorption bands at 430 and 690 nm allowing it to absorb light in the whole visible spectrum. The resulting highly conjugated polymer showed electrochromic behavior and the color changes from neutral-state green to oxidized-state dark blue. The electrogenerated thin film of the polymer displayed good hole mobility in solid state and registered a photo-electrochemical response when light was applied.

The synthesis and physicochemical properties of a new class of BODIPY-based donor-acceptor π-conjugated polymers are presented. Solution-processed top-gate/bottom-contact (TG-BC) thin-film transistors on flexible plastic substrates exhibit air-stable p-channel activities with charge carrier mobilities as high as 0.17 cm(2) /V·s and current on/off ratios of 10(5) -10(6) , the highest reported to date for a BODIPY-based semiconductor. The results shown here indicate a significant charge-transport improvement (>10000×) in BODIPY-based polymeric semiconductors, demonstrating its potential in future organic optoelectronic applications.

Two fabrication schemes are reported for the direct patterning of organic monolayers on oxide-free silicon, combining top-down nanoimprint lithography and bottom-up monolayer formation. The first approach was designed to form monolayer patterns on the imprinted areas, while the second approach was designed for monolayer formation outside of the imprinted features. By both approaches, covalently bonded Si-C monolayer patterns with feature sizes ranging from 100 nm to 100 microm were created via a hydrosilylation procedure using diluted reagents. Both unfunctionalized and omega-functionalized alkenes were patterned successfully.

A sugar and pH dual-responsive controlled release system, which is highly specific towards molecular stimuli, has been developed based on the binding between catechol and boronic acid on a platform of mesoporous silica nanoparticles (MSNs). By grafting phenylboronic acid stalks onto the silica surface, catechol-containing β-cyclodextrins can be attached to the orifices of the MSNs' nanopores through formation of boronate esters which block access to the nanopores. These esters are stable enough to prevent cargo molecules from escaping. The boronate esters disassociate in the presence of sugars, enabling the molecule-specific controlled-release feature of this hybrid system. The rate of release has been found to be tunable by varying both the structures and the concentrations of sugars, as a result of the competitive binding nature associated with the mechanism of its operation. Acidification also induces the release of cargo molecules. Further investigations show that the presence of both a low pH and sugar molecules provides cooperative effects which together control the rate of release.

Two new monomers, 2-benzyl-5,12-dihydro-2 H -pyrrolo[3′,4′:2,3][1,4]dioxocino[6,7- b ]quinoxaline (DPOQ) and 5,12-dihydrothieno[3′,4′:2,3][1,4]dithiocino[6,7- b ]quinoxaline (DTTQ), were synthesized. The chemical structures of the monomers were characterized by nuclear magnetic resonance ( 1 H NMR), Fourier transform infrared (FTIR) and mass spectra. Copolymer of DPOQ with bithiophene (BT) was synthesized via potentiostatic electrochemical polymerization in acetonitrile–tetrabutylammonium tetrafluoroborate solvent–electrolyte couple. For DTTQ, copolymerization with bithiophene was achieved via potentiodynamic method in dichloromethane–tetrabutylammonium hexafluorophosphate solvent–electrolyte couple. Characterizations of the resulting copolymers were performed by cyclic voltammetry (CV), FTIR, scanning electron microscopy (SEM) and UV–Vis spectroscopy. Four-probe technique was used to measure the conductivities of the samples. Moreover, the spectroelectrochemical and electrochromic properties of the copolymer films were investigated. In addition, dual type polymer electrochromic devices based on P(DPOQ-co-BT) and P(DTTQ-co-BT) with poly(3,4-ethylenedioxythiophene) were constructed. Spectroelectrochemistry, electrochromic switching and open circuit stability of the devices were studied. They were found to have good switching times, reasonable contrasts and optical memories.

We report on a 17-year-old man who presented with unreported combination of right sided microtia and preauricular skin tag with conductive hearing loss, unilateral renal agenesis, partial syndactyly of forth and fifth metacarpals, multiple tarsal coalitions, absent toe, and hypoplastic tibia and fibula. Radiological and clinical findings did not match with the previously described syndromes with the type of anomalies seen in the case. We propose that this represents a new syndrome.

Energy transfer cassettes composed entirely of boradiazaindacene (Bodipy) units were designed and synthesized to capture photonic energy and convert it to longer wavelength fluorescence emission. The new energy transfer systems obtained by simple condensation reactions are capable of elaborating efficient energy transfer from donor Bodipy units to the distyryl-Bodipy acceptor. (C) 2009 Elsevier Ltd. All rights reserved.

[reaction: see text] Click chemistry has been successfully applied in the synthesis of a bay region tetraboron-dipyrrin (BODIPY) appended perylenediimide (PDI). This light-harvesting molecule presents a large cross section for the absorption of light in the visible region. Excitation energy is efficiently channeled to the perylenediimide core. This novel antenna system is the first demonstration of the efficiency of energy transfer in a BODIPY-PDI bichromophoric system and appears to be highly promising for the design and synthesis of similar dendritic structures.

The recently reported acenaphthopyrrolone (ACNP) class of fluorophores have remarkably bright emission in the red end of the visible spectrum. We demonstrated that straightforward derivatization with 2-aminoethyl-dipicolylamine yields a selective and sensitive chemosensor for Zn(II), Cd(II) and Hg(II) ions. Further modifications could result in water-soluble derivatives, with practical applications in intracellular imaging of Zn(II) concentrations.

The incorporation of silica nanoparticles into drug delivery vehicles, and other nanotech platforms, has experienced rapid and significant growth over the past decade. However, as these nanoparticle-based systems become more and more complex, the methods used to analyze these systems have evolved at a comparatively much slower pace, resulting in the need for researchers to expand their toolbox and devise new strategies to characterize these materials. This article describes how X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) were recently employed in the analysis of two separate drug delivery systems which contain organic compounds covalently attached to the surfaces of silica nanoparticles. These techniques provided a deluge of qualitative and quantitative information about these drug delivery systems, and have several clear advantages over more common characterization procedures such as Fourier transform infrared spectroscopy (FT-IR) and solid state nuclear magnetic resonance (SSNMR). Thus, XPS and ToF-SIMS should be an integral component of the standard characterization protocol for any nanoparticle-based assemblies-particularly silica-based drug delivery systems-as this field of research continues to develop.

Competition with a monovalent cyclodextrin host (blue cones) in solution drives the multivalent binding of a Eu(3+) complex and a sensitizer molecule to cyclodextrin monolayers through a nonlinear self-assembly process. Adamantyl groups (light-blue spheres) are attached to the EDTA ligand (black) and the antenna molecule (orange), which has a carboxylate group for coordination to the Eu(3+) ion (yellow or red in free or complexed form, respectively).

Organization of molecules on surfaces is of utmost importance for the construction of functional materials. Non-covalent, weak and reversible supramolecular interactions provide this organization with high specificity and selectivity. The integration of different supramolecular systems is essential for the assembly of complex and functional architectures on surfaces. Self-assembly, in particular orthogonal self-assembly, is the main route to achieve these integrated architectures. This review article gives an overview of the recent developments of orthogonal supramolecular interactions on surfaces. The first part deals with the use of noncovalent interactions, including hydrogen bonding, metal coordination, electrostatics and host–guest interactions, to modify surfaces. The second part describes the combination of different orthogonal supramolecular interaction motifs for the generation of hybrid assemblies and materials

The mutual interaction of localized magnetic moments and their interplay with itinerant conduction electrons in a solid are central to many phenomena in condensed-matter physics, including magnetic ordering and related many-body phenomena such as the Kondo effect(1), the Ruderman-Kittel-Kasuya-Yoshida interaction(2) and carrier-induced ferromagnetism in diluted magnetic semiconductors(3). The strength and relative importance of these spin phenomena are determined by the magnitude and sign of the exchange interaction between the localized magnetic moments and also by the mean distance between them. Detailed studies of such systems require the ability to tune the mean distance between the localized magnetic moments, which is equivalent to being able to control the concentration of magnetic impurities in the host material. Here, we present a method for doping a gold film with localized magnetic moments that involves depositing a monolayer of a metal terpyridine complex onto the film. The metal ions in the complexes can be cobalt or zinc, and the concentration of magnetic impurities in the gold film can be controlled by varying the relative amounts of cobalt complexes (which carry a spin) and zinc complexes (which have zero spin). Kondo and weak localization measurements demonstrate that the magnetic impurity concentration can be systematically varied up to similar to 800 ppm without any sign of inter-impurity interaction. Moreover, we find no evidence for the unwanted clustering that is often produced when using alternative methods.

Multivalency is present in many biological and synthetic systems. Successful application of multivalency depends on a correct understanding of the thermodynamics and kinetics of this phenomenon. In this Article, we address the stability and strength of multivalent bonds with force spectroscopy techniques employing a synthetic adamantane/β-cyclodextrin model system. Comparing the experimental findings to theoretical predictions for the rupture force and the kinetic off-rate, we find that when the valency of the complex is increased from mono- to di- to trivalent, there is a transition from quasi-equilibrium, with a constant rupture force of 99 pN, to a kinetically dependent state, with loading-rate-dependent rupture forces from 140 to 184 pN (divalent) and 175 to 210 pN (trivalent). Additional binding geometries, parallel monovalent ruptures, single-bound divalent ruptures, and single- and double-bound trivalent ruptures are identified. The experimental kinetic off-rates of the multivalent complexes show that the stability of the complexes is significantly enhanced with the number of bonds, in agreement with the predictions of a noncooperative multivalent model.

Micrometer-scale monolayer patterns of a phosphorus-containing molecular precursor are fabricated on nearly intrinsic Si(100) using nanoimprint lithography. The patterned sample is protected by a SiO2capping layer applied by electron beam evaporation and subjected to rapid thermal annealing (RTA) to diffuse the phosphorus dopant atoms into the bulk silicon locally.

Anthrax is an acute disease, concurrently a potential biological warfare agent caused by Bacillus Anthracis. The accurate, rapid, sensitive, and selective detection of Bacillus spores plays a vital role in order to prevent a biological attack or outbreak of disease. Bacterial spores contain a main core cell which is enclosed by protective layers. As a major component of these protective layers, bacterial spores contain up to 1 M dipicolinic acid (DPA), accounting for 5−15 % of the dry mass of the bacterial spore. Hence, DPA is a convenient biomarker for these spores. In recent years a number of biological and chemical detection methods for Bacillus Anthracis spores have been investigated. Biological methods are based on polymerase chain reactions and immunoassays. Important chemical methods employ vibrational spectroscopy (FT-IR, Raman and SERS) and photoluminescence. Among them, lanthanide (Ln3+)-based luminescent detection of DPA has been most promising owing to the unique photophysical properties of Ln3+-DPA chelates, including their bright luminescence upon sensitization by DPA, the long luminescence lifetimes compared to free Ln3+, and the concomitantly high luminescence enhancement ratio upon coordination of DPA to the Ln3+ center. Besides the use of DPA itself as a sensitizer, ratiometric fluorescent detection of anthrax spores can be achieved through the displacement of a different sensitizer by DPA.

Assembly of a mixture of guest-functionalized antenna and Eu(3+)-complexed ligand molecules in a patterned fashion onto a receptor surface provides efficient localized sensitized emission. Coordination of a carboxylate group of the antenna to the Eu(3+) center and noncovalent anchoring of both components to the receptor surface appeared to be prerequisites for efficient energy transfer. A Job plot at the surface confirmed that coordination of the antenna to the Eu(3+) center occurs in a 1:1 fashion. The efficiency of this intramolecular binding process is promoted by the high effective concentration of both complementary moieties at the surface. The system constitutes therefore an example of supramolecular expression of a complex consisting of several different building blocks which signals its own correct formation.

We developed a novel boradiazaindacene derivative to detect cyanide ions in solution at micromolar concentrations. This structurally simple chemosensor displays a large decrease in emission intensity and a reversible color change from red to blue on contact with cyanide ions. Highly fluorescent polymeric films can be obtained by doping with the chemosensor. Such polymeric materials can be used for the sensing of the cyanide ions in polymer matrices. © 2008 American Chemical Society.

(Chemical Equation Presented) A novel distyryl-substituted boradiazaindacene (BODIPY) dye displays interesting properties as a sensitizer in DSSC systems, opening the way to further exploration of structure-efficiency correlation within this class of dyes. © 2008 American Chemical Society.

Aryl-substituted boratriazaindacenes (Aza-Bodipy's) are a new class of dyes with long wavelength absorption and emissions. We now report the first application of these dyes in metal ion sensing. 2-Pyridyl substituents at positions 1 and 7 create a well-defined pocket for metal ion binding. The chemosensor described here is selective for Hg(II) ions, and both absorption and emission spectra display large changes that would allow ratiometric sensing. [reaction: see text].

Encephaloceles are uncommon and can arise from congenital, traumatic, or spontaneous origins. Approximately 80% of all cerebrospinal fluid rhinorrheas are caused by head injuries. Spontaneous or nontraumatic encephaloceles or cerebrospinal fluid leaks have been the least common in most series, accounting for only 3% to 5% of all cerebrospinal fluid leaks. There is a high incidence of meningitis and brain abscess. Thus, early diagnosis is very important. We present an adult patient with uncomplicated nontraumatic cerebrospinal fluid rhinorrhea that was caused by spontaneous trans-sphenoidal encephalocele.

Pneumoceles of the frontal sinus are very rare conditions, characterized by abnormal expansion of the frontal sinus. The patient usually complains of slowly changing facial contours. The etiology and pathogenesis of pneumoceles remains unclear. A case of pneumocele of the frontal sinus is presented, and the differentiated features of the disease are discussed.