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The effective separation of a mixed peptide sample has been achieved via a computational strategy towards the bespoke design of a new silica bound supramolecular host capable of selectively interacting with different peptides via their morphology and amino acid functionalities. The experimental and in silico chromatographic behaviour of a sample of mixed peptides on a new co-pillar[4+1]arene bound silica HPLC stationary phase column was compared with RP-C18 and unfunctionalized silica (normal phase) column via liquid chromatography coupled with mass spectrometry (LC-MS/MS) and demonstrates superior separation selectivity and sensitivity for the mixed peptide solution being investigated.

Nanometer scale rods of superparamagnetic iron oxide have been encapsulated, along with the anti-cancer therapeutic carnosine, inside porous poly(lactic

It is necessary to develop a resilient food supply that will withstand unexpected future shocks and deliver the required amounts of nutrients to consumers. By increasing the sustainability of food and agriculture, the food system will be able to handle challenges such as climate change, declining agricultural resources, growing population/urbanization, pandemics, and recessions/shortages. Micronutrient deficiency, otherwise called hidden hunger, is one of the major malnutrition consequences worldwide, particularly in middle- or low- income countries. Unlike essential mineral or nutrient compounds, micronutrients could be less of a priority due to their small levels of requirement. However, insufficient micronutrients caused critical adverse health symptoms and are excessively vital for young children’s development. Therefore, there have been numerous attempts to enhance minerals and nutrients in food crops, including biofortification, food fortification, and supplementation. Based on several interventions involving micronutrients, modern technology, such as nanotechnology, can be applied to enhance sustainability and to reduce the food system’s environmental impact. Previous studies have addressed various strategies or interventions to mitigate major micronutrient deficiency including iron, iodine, zinc, and vitamin A. Comparably small amounts of studies have addressed vitamin B12 deficiency and its fortification in food crops. Vitamin B12 deficiency causes serious adverse health effects, including in the nervous or blood systems, and occurs along with other micronutrient deficiencies, such as folate, iron, and zinc, worldwide, particularly in middle- and low-income countries. Mitigation for B12 deficiency has mainly focused on developing pharmacological and medical treatments such as vitamin B12 serum or supplements. Further studies are required to undertake a sustainable approach to fortify vitamin B12 in plant-based food sources for public health worldwide. This review paper highlights nanoparticle application as a promising technology for enhancing vitamin B12 without conventional genetic modification requirements. The nanoparticle can efficiently deliver the mineral/nutrient using coating techniques to targeted sites into the plant. This is mainly because nanoparticles have better solubility and permeability due to their nano size with high surface exposure. Vitamin B12-coated nanoparticles would be absorbed, translocated, and accumulated by the plant and eventually enhance the bioavailability in food crops. Furthermore, by reducing adverse environmental effects, such as leaching issues that mainly occur with conventional fertilizer usage, it would be possible to develop more sustainable food fortification.

A silica-bound C-butylpyrogallol[4]arene chromatographic stationary phase was prepared and characterised by thermogravimetric analysis, scanning electron microscopy, NMR and mass spectrometry. The chromatographic performance was investigated by using C60 and C70 fullerenes in reverse phase mode via flash column and high-pressure liquid chromatography (HPLC). The resulting new stationary phase was observed to demonstrate size-selective molecular recognition as postulated from our in-silico studies. The silica-bound C-butylpyrogallol[4]arene flash and HPLC stationary phases were able to separate a C60- and C70-fullerene mixture more effectively than an RP-C18 stationary phase. The presence of toluene in the mobile phase plays a significant role in achieving symmetrical peaks in flash column chromatography.

Simple Summary Nanotechnology is becoming widely accepted and being adapted for use in different fields. In the animal feed sector, there is potential for delivery of minerals using a nano format to increase bioavailability and digestibility. Broiler chickens and zinc were chosen as a model for examining nano mineral delivery. The trial showed that amino acid coated zinc improved bird growth and feed consumption and also improved digestibility of zinc. A further benefit was an improvement in leg strength of the supplemented birds. This suggests that coated nano delivery of minerals can improve their bioavailability with implications for production of mineral supplements in the animal feed industry. Abstract Recently, nanotechnology has been widely adopted in many fields. The goal of this study was to evaluate the potential for amino acid coated nano minerals as a supplement in broiler feed. Zinc was selected as a model mineral for this test and supplementation of nano zinc, both coated and uncoated was compared with organic and inorganic commercial forms of zinc. A total of 48 pens (8 birds each) were assigned to one of the following dietary treatments: Control, methionine-Zinc chelate (M-Zn), nano zinc oxide (Nano-ZnO), and methionine coated nano zinc oxide (M-Nano-ZnO). All experimental diets were formulated with the same total zinc, methionine, protein, and energy content with just the zinc source as a variable. Bird weight, feed intake and feed conversion ratios were recorded weekly, with three birds culled (sacrificed) at day 21 and day 35 for sampling measures. Ileal digestibility of zinc was determined at day 21 and day 35 using titanium dioxide as an inert marker. Blood serum, liver and spleen samples were collected at day 21 and day 35 and analysed for zinc content via inductively coupled plasma mass spectrometry (ICP-MS). Tibia strength and morphometrics were measured from both legs of three birds per pen at day 21 and day 35. The study was conducted at Nottingham Trent University Poultry Unit, UK. The novel method of producing nano minerals coated with amino acids was successfully tested with zinc and material produced to test in the feeding study. Methionine coated nano zinc oxide supplementation significantly improved bird weight gain and the increased feed intake of broilers compared to an inorganic zinc form. Ileal digestibility was also improved with this methionine-nano zinc. Moreover, this supplementation improved the tibia strength of broilers at the age of 21 days, though this was not observed at day 35. Therefore, M-Nano-ZnO could be used to supplement broilers to improve both performance and digestibility with a limited positive impact on bone strength. The results of the current study suggest that the amino acid coating of nano minerals can improve the digestibility of minerals which may have further implications for the field of mineral nutrition in animal feeds.

Purpose\ud This work demonstrates specifically tailored microbubble‐based preparations and their suitability as MRI contrast agents for ingestion and measuring temporal and spatial pressure variation in the human stomach.\ud \ud Methods\ud Enhanced alginate spheres were prepared by incorporating gas‐filled microbubbles into sodium alginate solution followed by the polymerization of the mixture in an aqueous calcium lactate solution. The microbubbles were prepared with a phospholipid shell and perfluorocarbon gas filling, using a mechanical cavitational agitation regime. The NMR signal changes to externally applied pressure and coming from the enhanced alginate spheres were acquired and compared with that of alginate spheres without microbubbles. In vivo investigations were also carried out on healthy volunteers to measure the pressure variation in the stomach.\ud \ud Results\ud The MR signal changes in the contrast agent exhibits a linear sensitivity of approximately 40% per bar, as opposed to no measurable signal change seen in the control gas‐free spheres. This novel contrast agent also demonstrates an excellent stability in simulated gastric conditions, including at body temperature. In vivo studies showed that the signal change exhibited in the meal within the antrum region is between 5% and 10%, but appears to come from both pressure changes and partial volume artifacts.\ud \ud Conclusion\ud This study demonstrates that alginate spheres with microbubbles can be used as an MRI contrast agent to measure pressure changes. The peristaltic movement within the stomach is seen to substantially alter the overall signal intensity of the contrast agent meal. Future work must focus on improving the contrast agent's sensitivity to pressure changes.

Lithography is the most commonly used method for the selective metallisation of non-conductive surfaces in the manufacture of electronic devices such as printed circuit boards and antennae. However, when used in subtractive mode, lithography results in the generation of large amounts of organic solvent and metal containing waste and requires high initial capital investment. For these reasons, additive methods of selective metallisation are being widely investigated. In this work, a novel additive approach of Selective Metallisation using a Magnetic Field (SMMF) was studied. This method uses a magnetic catalyst to initiate the electroless plating process. Magnetic catalyst particles composed of magnetite-silicon dioxide-silver were synthesised by a wet-chemical procedure. Their composition was analysed by scanning electron microscopy and energy dispersive X-ray spectroscopy and the phase formation was confirmed by X-ray diffractometry. Catalytic activity towards formaldehyde oxidation and the magnetic properties of particles were confirmed by cyclic voltammetry and vibrating sample magnetometry, respectively. The results showed that the particles can be used as a catalyst for electroless copper plating and are attracted by the magnetic field. The pattern of deposition of the magnetic catalyst is defined by the magnetic field. Two different configurations of magnet and substrate were used to deposit the catalyst dispersion onto the substrate surface. In both cases, the particles were attracted by the magnetic field and deposited exclusively where the magnetic field was applied. Subsequent electroless copper plating also only occurred at these areas. Parallel lines of electroless copper were obtained. The effect of the magnetic field on magnetic catalyst deposition and subsequent electroless plating was studied and key process-specific defects were identified.

A novel co-pillar[4+1]arene incorporating two bromo-octyl substituents has been synthesised for the first time, using microwave irradiation in high yield (88%) in under four minutes, and bound to the surface of chromatographic silica particles. The resulting new stationary phase has been successfully utilised to separate xylene isomers via liquid chromatographic techniques.

Chronic diseases are rising in incidence and prevalence because of increases in life expectancy in many parts of the world coupled with advances in medicine which manage disease progression, rather than curing and alleviating the causes. Cataract is one such chronic condition. Identifying a therapeutic intervention that is successful in reversing or preventing cataracts may have applications for other chronic diseases of protein misfolding, such as diabetes and Alzheimer's disease as these have similar causation factors, notably oxidative stress and/or glycation. Cerium oxide nanoparticles (nanoceria) which have antioxidant, radioprotective and enzyme-mimetic properties have the potential to lead to an effective non-surgical treatment. However, nanoceria stability in physiological media is poor thus hindering their effective use in biomedical applications. Here we report a highly efficient one-pot synthesis of nanoceria (2–5 nm) coated with ethylene glycol, that is colloidally stable in physiological media and exhibits multiwavelength photoluminescence. The formulation, up to concentrations of 200 μg ml−1, was not toxic to human lens epithelial cells and had no adverse effect on the cellular morphology or proliferation rate. More significantly, these nanoceria showed protective effects against oxidative stress induced by hydrogen peroxide in lens epithelial cells. Electron microscopy studies show the internalization and cytoplasmic localization of the nanoceria was found to be largely in the perinuclear region.

A silica-bound C-butylpyrogallol[4]arene chromatographic stationary phase was prepared and characterised by thermogravimetric analysis, scanning electron microscopy, NMR and mass spectrometry. The chromatographic performance was investigated by using C60 and C70 fullerenes in reverse phase mode via flash column and high-pressure liquid chromatography (HPLC). The resulting new stationary phase was observed to demonstrate size-selective molecular recognition as postulated from our in-silico studies. The silica-bound C-butylpyrogallol[4]arene flash and HPLC stationary phases were able to separate a C60- and C70-fullerene mixture more effectively than an RP-C18 stationary phase. The presence of toluene in the mobile phase plays a significant role in achieving symmetrical peaks in flash column chromatography.

Two new psychoactive substances, namely 4-methylmethcathinone (mephedrone) and 5,6-methylenedioxy-2-aminoindane (MDAI) were analysed with a novel combination of microcrystalline tests followed by Raman micro-spectroscopy to facilitate their absolute identification. The discrimination power of the proposed combination was successfully demonstrated through the analysis of the positional isomers 2- and 3-methylmethcathinone. The addition of mercury dichloride as a microcrystalline test reagent produced specific microcrystals of each tested analyte. The robustness of the method was evaluated in the presence of common cutting agents (caffeine and benzocaine) as well as on street samples. The crystal lattice structures of mephedrone, 2-methylmethcathinone and MDAI mercury dichloride microcrystals were determined by single crystal X-ray diffraction. This confirmed the presence of both drug and reagent together in the lattice and accounts for the distinct habit of the observed microcrystals. Raman spectra of the formed microcrystals differed from those obtained from their standard salt form by loss and/or gain of some vibrational modes. Particularly important was the appearance of the mercury chloride link to each tested drug molecule which showed as strong bands at low wavenumbers. Its presence was corroborated by its detection in the crystal lattice. It was therefore concluded that microcrystalline testing followed by Raman micro-spectroscopy satisfies the technique combination requirement for psychoactive substances recommended by the Scientific Working Group for the Analysis of Seized Drugs (SWGDRUG) and provides a rapid and cheap analysis route. The proposed technique combination also aids the development of new microcrystalline tests as it allows for confirmation of the uniqueness of the developed microcrystals almost in-situ rather than growing single crystals for often long periods of time needed for single crystal X-ray diffraction analysis. Copyright © 2016 John Wiley & Sons, Ltd.

Selective metallization of non-conductive materials is used in electronic device manufacturing. It is usually achieved via a combination of the photolithography and metal deposition processes. However, this approach is expensive and results in the production of hazardous waste. Present research suggests a cost-effective alternative way of selective metallisation, namely, a gradient magnetic field is applied during catalyst deposition, prior to electroless copper plating (Figure 1, A). In order to enable an interaction with the magnetic field, the standard Pd/Sn catalyst was replaced by a novel magnetic catalyst, γ-Fe2O3-Ag composite nanoparticles (Figure 1, B). The catalyst was synthesised via a wet-chemical method at ambient conditions. The composition of the catalyst was confirmed by scanning electron microscopy and energy dispersive x-ray spectroscopy. The magnetic properties of the catalyst were confirmed whilst the catalytic activity towards formaldehyde oxidation was proven by cyclic voltammetry. A gradient magnetic field was achieved by the combined application of a permanent magnet and steel template. The distribution of the magnetic field was simulated prior to template fabrication. The catalyst was attracted by the magnetic field and deposited only at the areas with maximum magnetic field influence. Subsequent electroless copper plating occured exclusively at the areas where the magnetic field was focused and catalyst deposited. Tracks of copper (350 µm width and 1 mm gap) were prepared using this novel additive manufacturing process (Figure 1, C). Figure 1. A – schematic presentation of the process; B – novel magnetic catalyst γ-Fe2O3-Ag; C – selectively metallised substrate obtained by using novel magnetic catalyst and gradient magnetic field. Figure 1

Purpose The direct in-vivo measurement of fluid pressure cannot be achieved with MRI unless it is done with the contribution of a contrast agent. No such contrast agents are currently available commercially, whilst those demonstrated previously only produced qualitative results due to their broad size distribution. Our aim is to quantitate then model the MR sensitivity to the presence of quasi-monodisperse microbubble populations. Methods Lipid stabilised microbubble populations with mean radius 1.2 ± 0.8 μm have been produced by mechanical agitation. Contrast agents with increasing volume fraction of bubbles up to 4% were formed and the contribution the bubbles bring to the relaxation rate was quantitated. A periodic pressure change was also continuously applied to the same contrast agent, until MR signal changes were only due to bubble radius change and not due to a change in bubble density. Results The MR data compared favourably with the prediction of an improved numerical simulation. An excellent MR sensitivity of 23 % bar-1 has been demonstrated. Conclusion This work opens up the possibility of generating microbubble preparations tailored to specific applications with optimised MR sensitivity, in particular MRI based in-vivo manometry. Magn Reson Med 70:1409–1418, 2013. © 2012 Wiley Periodicals, Inc.

A series of resorcin[4]arene and pyrogallol[4]arene macrocycles have been synthesized efficiently within 5 min, affording crystalline products suitable for single crystal X-ray diffraction, utilising microwave irradiation in a ‘one-pot’ reaction whilst controlling the selective formation of the rccc cone stereoisomer.

A novel copillar[4+1]arene incorporating alkylthiol substituents was synthesised in three steps and structurally characterised as the first example of a pillar[n]arene to incorporate two terminal thiols on the same aromatic ring. The macrocycle was attached to gold electrodes through a standard dipping technique. Cyclic voltammetry demonstrated selectivity for Li+ over other alkali metal cations. The copillar[4+1]arene was also used as a capping agent in the preparation of 3 nm gold nanoparticles.

Pyrogallol[4]arenes form stable hydrogen-bonded nanocapsules that have unique properties that may make them suitable for diverse applications, such as catalysts and molecular transporters. Little is known about the behavior of the interior of these new materials in solution, and by using the solvent-dependent properties of 1-(9-anthryl)-3-(4-dimethylaniline) propane (ADMA), the inner phase properties of the hexamers are investigated. Steady-state and dynamic spectrofluorometric results are in agreement, are consistent with solid-state studies, and indicate that the majority of ADMA is sequestered in an extended conformation with the crystallization solvent. The conformational flexibility of ADMA is attributed to lower capsule occupancies ( approximately 50%, i.e., 1 molecule per 2 capsules, one occupied and one empty) relative to our previous study with pyrene butyric acid (occupancy of 150%, i.e., 1.5 molecules per capsule) in which the probe was restricted within a nanocapsule. The nature of the encapsulated ADMA complexes are found to change with time, as there is either fluorophore leaching from the capsule or endo-exo-capsule solvent exchange. However, the choice of crystallizing solvent (ethyl acetate or acetonitrile) and PgC(n) alkyl tail (C(6) or C(10)) does not influence experimental outcomes. These research findings give a better understanding of the encapsulation versatility of these unique supramolecular assemblies and the protective nanopockets that can exist for guest molecules.

Bowl-shaped C-methylcalix[4]resorcinarene forms a 1:1 ball-and-socket nanostructure with o-carborane through two endo-cavity BC-H...pi hydrogen bonds. In the presence of 4',2:6,4"-terpyridine, two of these nanostructures are held together by four terpyridines through sixteen OH...N hydrogen bonds, completely shrouding two carboranes.

The aldol condensation of an enolisable ketone and a benzaldehyde followed by Michael addition of the enone with a second enolisable ketone under solvent free conditions leads to the quantitative formation of a diketone, which can be readily converted to a pyridine (typically >80% overall yield) via a double condensation in the presence of ammonium acetate in acetic acid, allowing access to a diverse range of oligopyridyls including bipyridyls and terpyridyls.

A paradigm shift away from using solvents in organic synthesis as solventless reactions can lead to improved outcomes, and more benign synthetic procedures, in for example aldol condensation reactions, sequential aldol and Michael addition reactions en route to Krohnke type pyridines, reactions leading to 3-carboxycoumarins, benzylidenes, 4-aryl-1,4-dihydropyridines and 2-aryl-1,2,3,4-tetrahydroquinazolines, and oligomerisation reactions for the synthesis of cavitands; kinetic considerations for the reaction of two solids can only be explained if a eutectic melt is formed during the reaction.

Calix[4]resorcinarenes may be prepared in high yield and purity by direct reaction of resorcinol and benzaldehyde derivatives in the presence of a catalytic amount of solid acid and at ambient temperature under solvent-free conditions. This represents a viable alternative to traditional solution phase methodology. The solvent-free method measures up well with respect to energy usage, solvent wastes and associated hazards, reaction time and yield. In addition, the relevant benzaldehyde derivatives are prepared in polypropylene glycol, which is readily recycled.

The reaction of a diphenylpyridine with one equivalent of potassium tetrachloroplatinate in ethanoic acid yields a cyclometallated species which can be induced to undergo a second cyclometallation to give a C∧N∧C tridentate species. Carbonyl derivatives of two such compounds have been structurally characterised. The X-ray structure of the complex [2,6-(4′-C6H13OC6H3)2C5H3NPt(CO)], (1), obtained using 2,6-bis(4′-hexyloxyphenyl)pyridine, has no unusual features. In contrast, the structure of the complex [2,6-(C6H4)2-4-(4′-C8H17OC6H5)C5H2NPt(CO)], (2), which results when using 4-(4′-octyloxy-phenyl)-2,6-diphenylpyridine, has close intermolecular contacts, with a Pt–Pt “bond” of 3.243(1) A holding the molecules together as dimers. Compound 2 also exists in another form in the solid state, a form that does not appear to contain Pt–Pt bonds.

Metalation of 2,6-diphenylpyridine (1) by potassium tetrachloroplatinate in acetic acid gives a monocyclometalated chloride-bridged dimer 4. This dimer is split with CO to give a kinetic product 9t with the incoming CO trans to the orthometalated carbon. The kinetic product of cleavage is shown to be 16 kJ mol-1 higher in energy than the thermodynamic product 9c, which has the CO trans to the pyridine nitrogen. The isomerization of 9t to 9c is shown not to take place via an associative mechanism and, with analogue 11, is effectively suppressed when excess chloride is added, implying that it takes place via a chloride dissociation. The monocyclometalated 9 undergoes a second cyclometalation to give the C∧N∧C dicyclometalated complex 15 in high yield. This second cyclometalation is brought about by the simple expedient of adding water to the monocyclometalated precursor. The addition of water is rationalized on the basis of needing to ionize the HCl byproduct of the reaction. Using a substituted pyridine (5...

Upon crystallising a series of pyrogallol[4]arenes from ethyl acetate as hydrogen bonded nanocapsules, structural study allows for the determination of the dependence of inter-capsule spacing on the chain length present at the lower rims of these ‘bowl-shaped’ molecules. Surprisingly, these nanocapsules pack closest together when a hexyl chain length is employed, and reasons for this phenomenon are suggested.

A novel polar solvent-soluble tetra-functionalised cyano-footed calixarene forms a dimeric capsule, sealed via a hydrogen-bonding network between the two macrocycles, a single water molecule and a chloride anion, resulting in the encapsulation of a pyridinium guest, as shown in both solution and the solid state.

Chiral and achiral bipyridines are readily accessible via a solvent-free Michael addition involving solid NaOH, followed by treatment with ammonium acetate in acetic acid, as a ‘one pot’ more benign protocol, affording pure products in high yield, typically >80%.

The coordination polymer formed by the addition of zinc(II)chloride to 4′-(4‴-octyloxyphenyl)-4,2′-6′,4″-terpyridine (readily prepared using green chemistry principles) has been structurally authenticated using single crystal X-ray diffraction and microanalysis techniques. The polymeric network adopts a layered helical zigzag arrangement about a distorted tetrahedral Zn(II) centre, forming channels of inter-digitated alkyl chains.

The dynamic solution equilibria between molecular Borromean rings (BRs) and Solomon knots (SKs), assembled from transition metal-templated macrocycles, consisting of exo-bidentate bipyridyl and endo-tridentate diiminopyridyl ligands, have been examined with respect to the choice of the metal template and reaction conditions employed in the synthesis of the metalated BRs, otherwise known as Borromeates. Three new Borromeates, their syntheses templated by Cu(II), Co(II), and Mn(II), have been characterized extensively (two by X-ray crystallography) to the extent that the metal centers in the assemblies have been shown to be distanced sufficiently from each other not to communicate. The solid-state structure of the Co(II)-Borromeate reveals that six MeOH molecules, arranged in a [O--H...O] hydrogen bonded, chair-like conformation, are located within its oxophilic central cavity. When a mixture of Cu(II) and Zn(II) is used as the source of templation, there exists a dynamic equilibrium, in MeOH at room temperature, between a mixed-metal BR and a SK, from which the latter has been fractionally crystallized. By employing appropriate synthetic protocols with Zn(II) or Cd(II) as the template, significant amounts of SKs are formed alongside BRs. Modified crystallization conditions resulted in the isolation of both an all-zinc BR and an all-zinc SK, crystals of which can be separated manually, leading to the full characterization of the all-zinc SK by (1)H NMR spectroscopy and X-ray crystallography. This doubly interlocked [2]catenate has been identified retrospectively in recorded spectra, where it was attributed previously to a Borromeate with a Zn(II) cation coordinated to the oxophilic interior walls of the ensemble. Interestingly, these Zn(II)-templated assemblies do not interconvert in MeOH at room temperature, indicating the significant influence of both the metal template and solvent on the solution equilibria. It would also appear that d(10) metal ions favor SK formation-no evidence of Cu(II)-, Co(II)-, or Mn(II)-templated SKs has been found, yet a 1:0.9 ratio of BR:SK has been identified by (1)H NMR spectroscopy when Cd(II) is used as the template.

A paradigm shift away from using solvents in organic synthesis as solventless reactions can lead to improved outcomes, and more benign synthetic procedures, in for example aldol condensation reactions, sequential aldol and Michael addition reactions en route to Krohnke type pyridines, reactions leading to 3-carboxycoumarins, benzylidenes, 4-aryl-1,4-dihydropyridines and 2-aryl-1,2,3,4-tetrahydroquinazolines, and oligomerisation reactions for the synthesis of cavitands; kinetic considerations for the reaction of two solids can only be explained if a eutectic melt is formed during the reaction.

The aldol condensation of an enolisable ketone and a benzaldehyde followed by Michael addition of the enone with a second enolisable ketone under solvent free conditions leads to the quantitative formation of a diketone, which can be readily converted to a pyridine (typically >80% overall yield) via a double condensation in the presence of ammonium acetate in acetic acid, allowing access to a diverse range of oligopyridyls including bipyridyls and terpyridyls.

Superparamagnetic iron oxide nanometre scale particles have been utilised as contrast agents to image staked target binding oligonucleotide arrays using MRI to correlate the signal intensity and T(2)* relaxation times in different NMR fluids.

2,6-Diphenylpyridine is metalated twice by potassium tetrachloroplatinate in acetic acid to give in high yield a complex with a tridentate ligand bound to the metal via a C∧N∧C donor set. This complex and three derivatives have been characterized, including the single-crystal X-ray analysis of one derivative.

Dendritic cell derived exosomes are able to mediate and modulate immune responses in vivo by semi-direct T cell activation. T cells can eradicate primary, metastatic, relapsed tumours and ameliorate otherwise fatal viral infections. Not surprisingly activation and expansion of T cells has become one of the main focuses for immunotherapy. Using nanotechnology, we have developed targeted and traceable in vivo artificial exosomes by coating liposomes (FDA approved) with an optimized number of MHC Class I/peptide complexes and a selected specific range of ligands for adhesion, early activation, late activation and survival T cell receptors. These targeted artificial exosomes are traceable both in vitro and in vivo via fluorescent and Magnetic Resonance Imaging and facilitate imaging of specific areas by applying localised nuclear magnetic interactions of hydrogens via super paramagnetic labels. Here we show that artificial exosomes activate and expand functional antigen specific T cells at sufficient levels. This novel system has potential basic and clinical applications in immunology where the study of membrane interactions is desired.

A series of cyclometallated phenylpyridine platinum(II) complexes have been synthesised with a systematic variation in both the phenylpyridine and the ancillary ligand. Oxidation of one of the cyclometallated species leads to a number of isomeric platinum(IV) complexes, all of which eventually isomerise to a single compound. The route to these new compounds has been demonstrated to involve an initial slow oxidation followed by a rapid C–H activation to give doubly cyclometallated complexes. The solid state structures of a number of both the platinum(II) and the platinum(IV) species have been solved; many of the structures exhibited extended interactions that result in complex three dimensional packing.

13C NMR spectroscopy as well as the short bond between the platinum and the C4 atom of the pyridine ring in 1 (1.95 A) indicate the formation of a novel carbene species. Compound 1 is remarkably stable (m.p. 246°C), probably due to the presence of intramolecular hydrogen bonds, and is formed instead of the expected cyclometalated product. R=n-hexyl.