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The Ni(NCS)2(pyzdo)2 coordination polymer is found to be an S=1 spatially anisotropic square lattice with easy-axis single-ion anisotropy. This conclusion is based upon considering in concert the experimental probes x-ray diffraction, magnetic susceptibility, magnetic-field-dependent heat capacity, muon-spin relaxation, neutron diffraction, neutron spectroscopy, and pulsed-field magnetization. Long-range antiferromagnetic (AFM) order develops at TN=18.5K. Although the samples are polycrystalline, there is an observable spin-flop transition and saturation of the magnetization at ≈80T. Linear spin-wave theory yields spatially anisotropic exchanges within an AFM square lattice, Jx=0.235meV, Jy=2.014meV, and an easy-axis single-ion anisotropy D=-1.622meV (after renormalization). The anisotropy of the exchanges is supported by density functional theory.

A series of phenanthroline-oxazine ligands were formed by a cyclisation reaction between L-tyrosine amino acid esters and 1,10-phenanthroline-5,6-dione (phendione). The methyl derivative of the phenanthroline-oxazine ligand 1 was complexed with Ag(I), Mn(II) and Cu(II) to form [Ag(1)2]ClO4, [Mn(1)3](ClO4)2 and [Cu(1)3](ClO4)2. The activity of these metal complexes was tested against the bacteria Escherichia coli and Staphylococcus aureus. Each of the metal complexes was more active than 1 against S. aureus and the Mn(II) and Cu(II) complexes also showed greater activity than 1 towards E. coli. The effect of increasing the length of the alkyl moiety on the phenanthroline-oxazine ligands and their corresponding tris homoleptic Cu(II) complexes was investigated. In all cases both the ligands and their complexes were more active against Gram-positive S. aureus than against Gram-negative E. coli. Differences in the lipophilicity of the ligands and their corresponding Cu(II) complexes did alter the antibacterial activity, with the hexyl and octyl derivatives and their complexes showing the greatest activity and comparing well with clinically used antibiotics. The most active Cu(II) complexes and their respective ligands were also active against Methicillin-resistant S. aureus (MRSA). In vivo toxicity studies, conducted using the Galleria mellonella model, showed that all of the compounds were well tolerated by the insect larvae.

A series of phenanthroline-oxazine ligands were formed by a cyclisation reaction between L-tyrosine amino acid esters and 1,10-phenanthroline-5,6-dione (phendione). The methyl derivative of the phenanthroline-oxazine ligand 1 was complexed with Ag(I), Mn(II) and Cu(II) to form [Ag(1)2]ClO4, [Mn(1)3](ClO4)2 and [Cu(1)3](ClO4)2. The activity of these metal complexes was tested against the bacteria Escherichia coli and Staphylococcus aureus. Each of the metal complexes was more active than 1 against S. aureus and the Mn(II) and Cu(II) complexes also showed greater activity than 1 towards E. coli. The effect of increasing the length of the alkyl moiety on the phenanthroline-oxazine ligands and their corresponding tris homoleptic Cu(II) complexes was investigated. In all cases both the ligands and their complexes were more active against Gram-positive S. aureus than against Gram-negative E. coli. Differences in the lipophilicity of the ligands and their corresponding Cu(II) complexes did alter the antibacterial activity, with the hexyl and octyl derivatives and their complexes showing the greatest activity and comparing well with clinically used antibiotics. The most active Cu(II) complexes and their respective ligands were also active against Methicillin-resistant S. aureus (MRSA). In vivo toxicity studies, conducted using the Galleria mellonella model, showed that all of the compounds were well tolerated by the insect larvae.

Immunocompromised cancer patients are often at high risk of developing infections. Standard infection control measures are required to prevent the onset of infection but, under some circumstances, antimicrobial prophylaxis is necessary. We have developed a family of innovative metallo-antibiotics of general formula [Cu(N,N)(CipA)Cl] where N,N represents a phenanthrene ligand and CipA stands for a derivative of the clinically used fluoroquinolone antibiotic ciprofloxacin. The X-ray crystal structure of one member from this family, [Cu(phen)(CipA)Cl] (where phen is 1,10-phenanthroline), is also reported. These complexes combine into one drug entity a Cu-N,N-framework with DNA binding and DNA oxidant properties and an antibiotic derivative with known anti-proliferative and anti-microbial activities. The complexes were all found to exhibit excellent DNA recognition with binding affinity of lead agents in the order of ∼107 M(bp)−1. Biophysical studies involving calf thymus DNA indicate the complexes intercalate or semi-intercalate DNA via the minor groove. All complexes exhibited excellent nuclease activity with DNA strand scission being mediated predominantly via superoxide and hydroxyl radicals. The complexes were found to have promising anti-proliferative effects against a human breast adenocarcinoma cell line (MCF-7) and a human prostate carcinoma cell line (DU145) with low micromolar and, in some cases, nanomolar cytotoxicities observed. Selective targeting of Gram positive bacteria was also identified by this complex class with one lead compound having an order of magnitude greater potency against Methicillin-resistant S. aureus (MRSA) as compared to the CipA ligand. Importantly, from a clinical stand point, these complexes were also found to be well tolerated in an in vivo Galleria mellonella larvae model, which has both functional and structural similarities to that of the innate immune system of mammals.

Hydrazide ligand, (Z)-N'-(6-oxo-1,10-phenanthrolin-5(6H)-ylidene)isonicotinohydrazide, 1 forms from a 1:1 Schiff base condensation reaction between isoniazid (INH) and 1,10-phenanthroline-5,6-dione (phendione). Ag+ and Mn2+ complexes with 1:2 metal:ligand stoichiometry are prepared: [Ag(1)2]NO3, [Ag(1)2]BF4 and [Mn(1)2](NO3)2. Polymeric {[Ag(1)(NO3)]}n has 1:1 stoichiometry and forms upon infusion of CH2Cl2 into a DMSO solution of [Ag(1)2]NO3. {[Ag(1)(NO3)]}n was structurally characterized using X-ray crystallography. Metal-free 1 and its 1:2 complexes exhibit very good, broad-spectrum antimicrobial activity and are not excessively toxic to mammalian cells (A549 lineage).

Immunocompromised cancer patients are often at high risk of developing infections. Standard infection control measures are required to prevent the onset of infection but, under some circumstances, antimicrobial prophylaxis is necessary. We have developed a family of innovative metallo-antibiotics of general formula [Cu(N,N)(CipA)Cl] where N,N represents a phenanthrene ligand and CipA stands for a derivative of the clinically used fluoroquinolone antibiotic ciprofloxacin. The X-ray crystal structure of one member from this family, [Cu(phen)(CipA)Cl] (where phen is 1,10-phenanthroline), is also reported. These complexes combine into one drug entity a Cu-N,N-framework with DNA binding and DNA oxidant properties and an antibiotic derivative with known anti-proliferative and anti-microbial activities. The complexes were all found to exhibit excellent DNA recognition with binding affinity of lead agents in the order of ∼107 M(bp)−1. Biophysical studies involving calf thymus DNA indicate the complexes intercalate or semi-intercalate DNA via the minor groove. All complexes exhibited excellent nuclease activity with DNA strand scission being mediated predominantly via superoxide and hydroxyl radicals. The complexes were found to have promising anti-proliferative effects against a human breast adenocarcinoma cell line (MCF-7) and a human prostate carcinoma cell line (DU145) with low micromolar and, in some cases, nanomolar cytotoxicities observed. Selective targeting of Gram positive bacteria was also identified by this complex class with one lead compound having an order of magnitude greater potency against Methicillin-resistant S. aureus (MRSA) as compared to the CipA ligand. Importantly, from a clinical stand point, these complexes were also found to be well tolerated in an in vivo Galleria mellonella larvae model, which has both functional and structural similarities to that of the innate immune system of mammals.

Hydrazide ligand, (Z)-N'-(6-oxo-1,10-phenanthrolin-5(6H)-ylidene)isonicotinohydrazide, 1 forms from a 1:1 Schiff base condensation reaction between isoniazid (INH) and 1,10-phenanthroline-5,6-dione (phendione). Ag+ and Mn2+ complexes with 1:2 metal:ligand stoichiometry are prepared: [Ag(1)2]NO3, [Ag(1)2]BF4 and [Mn(1)2](NO3)2. Polymeric {[Ag(1)(NO3)]}n has 1:1 stoichiometry and forms upon infusion of CH2Cl2 into a DMSO solution of [Ag(1)2]NO3. {[Ag(1)(NO3)]}n was structurally characterized using X-ray crystallography. Metal-free 1 and its 1:2 complexes exhibit very good, broad-spectrum antimicrobial activity and are not excessively toxic to mammalian cells (A549 lineage).

Lysergic acid diethylamide (LSD) is perhaps one of the best-known psychoactive substances and many structural modifications of this prototypical lysergamide have been investigated. Several lysergamides were recently encountered as 'research chemicals' or new psychoactive substances (NPS). Although lysergic acid morpholide (LSM-775) appeared on the NPS market in 2013, there is disagreement in the literature regarding the potency and psychoactive properties of LSM-775 in humans. The present investigation attempts to address the gap of information that exists regarding the analytical profile and pharmacological effects of LSM-775. A powdered sample of LSM-775 was characterized by X-ray crystallography, nuclear magnetic resonance spectroscopy (NMR), gas chromatography mass spectrometry (GC-MS), high mass accuracy electrospray MS/MS, high performance liquid chromatography (HPLC) diode array detection, HPLC quadrupole MS, and GC solid-state infrared analysis. Screening for receptor affinity and functional efficacy revealed that LSM-775 acts as a nonselective agonist at 5-HT1A and 5-HT2A receptors. Head twitch studies were conducted in C57BL/6J mice to determine whether LSM-775 activates 5-HT2A receptors and produces hallucinogen-like effects in vivo. LSM-775 did not induce the head twitch response unless 5-HT1A receptors were blocked by pretreatment with the antagonist WAY-100,635 (1 mg/kg, subcutaneous). These findings suggest that 5-HT1A activation by LSM-775 masks its ability to induce the head twitch response, which is potentially consistent with reports in the literature indicating that LSM-775 is only capable of producing weak LSD-like effects in humans.

We report the observation of a novel nanostructured growth mode of the ceramic spinel zinc aluminate grown on c-sapphire in the form of epitaxially ordered twinned crystallites with pronounced vertically aligned “nanoblades” on top of these crystallites. The nanostructures are formed on bare c-sapphire substrates using a vapour phase transport method. Electron microscopy images reveal the nanostructure morphology and dimensions and allow direct and indirect observation of the twin boundary location in a number of samples. The nanoblade structure with sharply rising sidewalls gives rise to a distinctive bright contrast in secondary electron images in scanning electron microscopy measurements.

The selective extraction of specific proteins (non glycosylated, glycosylated or different glycoforms) from complex sample matrices utilising selective solid phase extration (SPE) is of significant interest within the fields of proteomics and glycoproteomics. Polymer monoliths have proven to be an excellent solid support for SPE applications in bio-analysis due to their excellent mass transfer characteristics for large biomolecules. Although biorecognition molecules such as lectins can be covalently immobilised directly onto the 10 monolith surface using a variety of chemistries, the relatively low surface area of these monoliths results in a correspondingly low sample capacity. Recently, we have described the covalent attachment of 20 nm gold nanoparticles (AuNPs) upon a polymer monolith with excellent surface coverage leading to a significant increase in surface area. In this work therefore wedescribe the in-situ preparation of an ethylene dimethacrylate porous polymer monolith within the confines of 20 μL polypropylene pipette tips, onto which methacrylate anchor sites were previously grafted to ensure intimate monolith/wall contact. Then AuNPs were immobilised onto the monolith pore 15 surface utilising azlactone cemistry. Field emission scanning electron microscopy was used to verify the high surface coverage of AuNPs. Erythrina cristagalli lectin (ECL) was immobilised upon the attached AuNPs via a biofunctional linker. The ECL-modified tip was successfully applied for the enrichment of galactosylated protein (desialated transferrin) versus a non-galactosylated protein (ribonuclease B) due to the specificity of ECL. Reversed phase capillary HPLC was used to validate the efficiency and selectivity of the developed micro-extraction phase which resulted in an increase in extraction recovery of ~95 % in the presence of AuNPs. The 20 specificity of the ECL-modified tip was further studied by using more complex mixture of proteins which included non-glycosylated prot

The selective extraction of specific proteins (non glycosylated, glycosylated or different glycoforms) from complex sample matrices utilising selective solid phase extration (SPE) is of significant interest within the fields of proteomics and glycoproteomics. Polymer monoliths have proven to be an excellent solid support for SPE applications in bio-analysis due to their excellent mass transfer characteristics for large biomolecules. Although biorecognition molecules such as lectins can be covalently immobilised directly onto the 10 monolith surface using a variety of chemistries, the relatively low surface area of these monoliths results in a correspondingly low sample capacity. Recently, we have described the covalent attachment of 20 nm gold nanoparticles (AuNPs) upon a polymer monolith with excellent surface coverage leading to a significant increase in surface area. In this work therefore wedescribe the in-situ preparation of an ethylene dimethacrylate porous polymer monolith within the confines of 20 μL polypropylene pipette tips, onto which methacrylate anchor sites were previously grafted to ensure intimate monolith/wall contact. Then AuNPs were immobilised onto the monolith pore 15 surface utilising azlactone cemistry. Field emission scanning electron microscopy was used to verify the high surface coverage of AuNPs. Erythrina cristagalli lectin (ECL) was immobilised upon the attached AuNPs via a biofunctional linker. The ECL-modified tip was successfully applied for the enrichment of galactosylated protein (desialated transferrin) versus a non-galactosylated protein (ribonuclease B) due to the specificity of ECL. Reversed phase capillary HPLC was used to validate the efficiency and selectivity of the developed micro-extraction phase which resulted in an increase in extraction recovery of ~95 % in the presence of AuNPs. The 20 specificity of the ECL-modified tip was further studied by using more complex mixture of proteins which included non-glycosylated prot

The selective extraction of specific proteins (non glycosylated, glycosylated or different glycoforms) from complex sample matrices utilising selective solid phase extration (SPE) is of significant interest within the fields of proteomics and glycoproteomics. Polymer monoliths have proven to be an excellent solid support for SPE applications in bio-analysis due to their excellent mass transfer characteristics for large biomolecules. Although biorecognition molecules such as lectins can be covalently immobilised directly onto the 10 monolith surface using a variety of chemistries, the relatively low surface area of these monoliths results in a correspondingly low sample capacity. Recently, we have described the covalent attachment of 20 nm gold nanoparticles (AuNPs) upon a polymer monolith with excellent surface coverage leading to a significant increase in surface area. In this work therefore wedescribe the in-situ preparation of an ethylene dimethacrylate porous polymer monolith within the confines of 20 μL polypropylene pipette tips, onto which methacrylate anchor sites were previously grafted to ensure intimate monolith/wall contact. Then AuNPs were immobilised onto the monolith pore 15 surface utilising azlactone cemistry. Field emission scanning electron microscopy was used to verify the high surface coverage of AuNPs. Erythrina cristagalli lectin (ECL) was immobilised upon the attached AuNPs via a biofunctional linker. The ECL-modified tip was successfully applied for the enrichment of galactosylated protein (desialated transferrin) versus a non-galactosylated protein (ribonuclease B) due to the specificity of ECL. Reversed phase capillary HPLC was used to validate the efficiency and selectivity of the developed micro-extraction phase which resulted in an increase in extraction recovery of ~95 % in the presence of AuNPs. The 20 specificity of the ECL-modified tip was further studied by using more complex mixture of proteins which included non-glycosylated prot

c-axis aligned ZnO nanorods were deposited by vapour phase transport on textured chemical bath deposited buffer layers. In this work we examine the role of the buffer layer and how it influences the vapour phase transport deposition process using both scanning and scanning transmission electron microscopes and related techniques. Vapour phase transport deposition on chemical bath deposited buffer is a complex growth process with many simultaneously effects including; (i) substantial morphological transformation at high temperature, which influences the base of the nanorods; (ii) the formation of a mixed amorphous / crystalline ZnxSi1-xOy interface during the vapour phase transport growth on silicon substrates; (iii) the overgrowth of the ZnO seed layers, by the silica interface rendering them inactive for nanorod nucleation, suggesting there is a minimum critical thickness ZnO buffer layer necessary for vapour phase transport growth of ZnO nanorods on silicon substrates. We discuss the relative importance of these effects on the overall growth process and use this understanding to explain previous results in the literature.

• To in situ fabricate ethylene dimethacrylate porous polymer monoliths within the confines of a commercial 20 μL polypropylene pipette tips. • To enhance the monolith surface area by immobilising AuNPs and then functionalise the AuNPs with ECL lectin for selective extraction of galactosylated proteins from complex media.

• To in situ fabricate ethylene dimethacrylate porous polymer monoliths within the confines of a commercial 20 μL polypropylene pipette tips. • To enhance the monolith surface area by immobilising AuNPs and then functionalise the AuNPs with ECL lectin for selective extraction of galactosylated proteins from complex media.

Polyaniline (PANI) is an organic polymer that has generated significant interest as an electrically conductive material component, and is used in applications such as sensors and flexible displays. A significant number of PANI-based devices have been prepared using inkjet printing; a fabrication technique favoured for its additive patterning ability and its efficient use of material. Combining precious metals and conducting organic polymers through compositing provides combinatorial materials, potentially possessing both the properties of the metallic component and the conducting polymer, as well as unique ensuing properties due to the compositing itself. The type of research is critical for driving innovation in materials research. Exploiting an established oxidative polymerisation protocol for producing stable nanodispersions of PANI was used where the standard oxidant was replaced with HAuCl4 or AgNO3 at a range of monomer:oxidant ratios to produce a range of composite dispersions. The morphology and populations of the metallic structures (including spherical nanoparticles and nano-whiskers), as well as the quality of the PANI were shown to be influenced by the concentration and type of oxidant used. This area of research is currently in its infancy where the research is focusing on demonstrating composite synthesis rather than the application of these materials for device fabrication. However, anticipated applications of these composite materials include noble metal deposition, electro-catalysis, neural tissue engineering, sensors, photovoltaic cells and memory devices.

Polyaniline (PANI) is an organic polymer that has generated significant interest as an electrically conductive material component, and is used in applications such as sensors and flexible displays. A significant number of PANI-based devices have been prepared using inkjet printing; a fabrication technique favoured for its additive patterning ability and its efficient use of material. Combining precious metals and conducting organic polymers through compositing provides combinatorial materials, potentially possessing both the properties of the metallic component and the conducting polymer, as well as unique ensuing properties due to the compositing itself. The type of research is critical for driving innovation in materials research. Exploiting an established oxidative polymerisation protocol for producing stable nanodispersions of PANI was used where the standard oxidant was replaced with HAuCl4 or AgNO3 at a range of monomer:oxidant ratios to produce a range of composite dispersions. The morphology and populations of the metallic structures (including spherical nanoparticles and nano-whiskers), as well as the quality of the PANI were shown to be influenced by the concentration and type of oxidant used. This area of research is currently in its infancy where the research is focusing on demonstrating composite synthesis rather than the application of these materials for device fabrication. However, anticipated applications of these composite materials include noble metal deposition, electro-catalysis, neural tissue engineering, sensors, photovoltaic cells and memory devices.

Polyaniline (PANI) is an organic polymer that has generated significant interest as an electrically conductive material component, and is used in applications such as sensors and flexible displays. A significant number of PANI-based devices have been prepared using inkjet printing; a fabrication technique favoured for its additive patterning ability and its efficient use of material. Combining precious metals and conducting organic polymers through compositing provides combinatorial materials, potentially possessing both the properties of the metallic component and the conducting polymer, as well as unique ensuing properties due to the compositing itself. The type of research is critical for driving innovation in materials research. Exploiting an established oxidative polymerisation protocol for producing stable nanodispersions of PANI was used where the standard oxidant was replaced with HAuCl4 or AgNO3 at a range of monomer:oxidant ratios to produce a range of composite dispersions. The morphology and populations of the metallic structures (including spherical nanoparticles and nano-whiskers), as well as the quality of the PANI were shown to be influenced by the concentration and type of oxidant used. This area of research is currently in its infancy where the research is focusing on demonstrating composite synthesis rather than the application of these materials for device fabrication. However, anticipated applications of these composite materials include noble metal deposition, electro-catalysis, neural tissue engineering, sensors, photovoltaic cells and memory devices.

Polyaniline (PANI) is an organic polymer that has generated significant interest as an electrically conductive material component, and is used in applications such as sensors and flexible displays. A significant number of PANI-based devices have been prepared using inkjet printing; a fabrication technique favoured for its additive patterning ability and its efficient use of material. Combining precious metals and conducting organic polymers through compositing provides combinatorial materials, potentially possessing both the properties of the metallic component and the conducting polymer, as well as unique ensuing properties due to the compositing itself. The type of research is critical for driving innovation in materials research. Exploiting an established oxidative polymerisation protocol for producing stable nanodispersions of PANI was used where the standard oxidant was replaced with HAuCl4 or AgNO3 at a range of monomer:oxidant ratios to produce a range of composite dispersions. The morphology and populations of the metallic structures (including spherical nanoparticles and nano-whiskers), as well as the quality of the PANI were shown to be influenced by the concentration and type of oxidant used. This area of research is currently in its infancy where the research is focusing on demonstrating composite synthesis rather than the application of these materials for device fabrication. However, anticipated applications of these composite materials include noble metal deposition, electro-catalysis, neural tissue engineering, sensors, photovoltaic cells and memory devices.

Organic polyazido substituted compounds are at the forefront of high energy research. Polyazido organic compounds have high relative heats of formation as one azido group adds about 87 kcal/mol of endothermicity to a hydrocarbon compound. In this family of compounds, 3,6-di(azido)-tetrazine (1), has the highest reported heat of formation ~ 1101 kJ mol-1 (6709 kJ kg-1). The compound 4,4',6,6'-tetra(azido)azo-1,3,5-triazine (2), has a heat of formation of 2171 (6164 kJ kg -1) (Fig. 1). Recently it was demonstrated that 1 and 2 were good precursors to nano carbon nitride materials. Thermal decomposition of 1 and 2 yields nitrogen-rich nanolayered, nanoclustered and nanodendritic carbon nitrides depending on the different heating processes., Sponsored in part by the Office of Naval Research and the National Science Foundation, Grant no. CHE0315275. Prepared in collaboration with the Space and Missile Propulsion Division, Air Force Research Laboratory, Edwards AFB, CA and NASA Solid Propellants Branch, Marshall Space Flight Center, Huntsville, AL, Published in Angewandte Chemie, v118, p7420-7423, 2006.

Organic polyazido substituted compounds are at the forefront of high energy research. Polyazido organic compounds have high relative heats of formation as one azido group adds about 87 kcal/mol of endothermicity to a hydrocarbon compound. In this family of compounds, 3,6-di(azido)-tetrazine (1), has the highest reported heat of formation ~ 1101 kJ mol-1(6709 kJ kg-1). The compound 4,4',6,6'-tetra(azido)azo-1,3,5-triazine (2), has a heat of formation of 2171 (6164 kJ kg -1). Recently it was demonstrated that 1 and 4 were good precursors to nano carbon nitride materials. Thermal decomposition of 1 and 4 yields nitrogen-rich nanolayered, nanoclustered and nanodendritic carbon nitrides depending on the different heating processes., Prepared in cooperation with the Space and Missile Propulsion Division, Air Force Research Laboratory, Edwards AFB, CA and the NASA Solid Propellants Branch, Marshall Space Flight Center, AL. Published in Angewandte Chemie, v45, p7262-7265, 2006. Original document contains color images.