Supplementing cold plasma with heat enables doping and nano-structuring of metal oxides

Nitrogen doped SnO2 polycrystalline nanostructures were produced from commercial SnO powders in a new system that combines a low-temperature plasma with heating. The method has the potential to improve the initial efficiency and the cycling performance of SnO2 anodes in Li-ion batteries. With this system, the temperature of the SnO to SnO2 conversion was lowered from 430 to 320 °C, up to 5 at% of doped nitrogen was detected and a nano-scale polycrystalline structure was observed in the product. Combining heat and low-pressure plasma is a promising approach for the production and treatment of enhanced energy storage materials.

Phosphorus-carbon nanocomposite anodes for lithium-ion and sodium-ion batteries

With the expected theoretical capacity of 2596 mA h g-1, phosphorus is considered to be the highest capacity anode material for sodium-ion batteries and one of the most attractive anode materials for lithium-ion systems. This work presents a comprehensive study of phosphorus-carbon nanocomposite anodes for both lithium-ion and sodium-ion batteries. The composite electrodes are able to display high initial capacities of approximately 1700 and 1300 mA h g-1 in lithium and sodium half-cells, respectively, when the cells are tested within a larger potential windows of 2.0-0.01 V vs. Li/Li+ and Na/Na+. The level of demonstrated capacity is underpinned by the storage mechanism, based on the transformation of phosphorus to Li3P phase for lithium cells and an incomplete transformation to Na3P phase for sodium cells. The capacity deteriorates upon cycling, which is shown to originate from disintegration of electrodes and their delamination from current collectors by post-cycling ex situ electron microscopy. Stable cyclic performance at the level of ∼700 and ∼350-400 mA h g-1 can be achieved if the potential windows are restricted to 2.0-0.67 V vs. Li/Li+ for lithium and 2-0.33 vs. Na/Na+ for sodium half-cells. The results are critically discussed in light of existing literature reports

Optimisation of the microencapsulation of tuna oil in gelatin-sodium hexametaphosphate using complex coacervation.

The microencapsulation of tuna oil in gelatin-sodium hexametaphosphate (SHMP) using complex coacervation was optimised for the stabilisation of omega-3 oils, for use as a functional food ingredient. Firstly, oil stability was optimised by comparing the accelerated stability of tuna oil in the presence of various commercial antioxidants, using a Rancimat™. Then zeta-potential (mV), turbidity and coacervate yield (%) were measured and optimised for complex coacervation. The highest yield of complex coacervate was obtained at pH 4.7 and at a gelatin to SHMP ratio of 15:1. Multi-core microcapsules were formed when the mixed microencapsulation system was cooled to 5 °C at a rate of 12 °C/h. Crosslinking with transglutaminase followed by freeze drying resulted in a dried powder with an encapsulation efficiency of 99.82% and a payload of 52.56%. Some 98.56% of the oil was successfully microencapsulated and accelerated stability using a Rancimat™ showed stability more than double that of non-encapsulated oil.

Targeting the sodium iodide symporter (NIS) and apoptotic genes in extrathyroidal tumors.

Sodium Iodide Symporter (NIS), a therapeutic gene, was studied for the first time in retinoblastoma (RB) correlating the expression with clinicopathological invasiveness of the tumor. The specificity of EpCAM based NIS gene therapy was demonstrated in breast cancer cell as a proof of concept model via 1) EpCAM as tissue specific promoter and 2) nanoformulation, both of which showed encouraging outcomes. In addition, for the first time the upregulated expression of splice variants of survivin, Bax and Bcl-2 in RB tumors was explored indicating their possible role in tumor progression through apoptosis dysregulation. Thus, the above study achieved a profound knowledge about NIS and apoptotic genes in extrathyroidal tumors.

Structure and dynamics in solid state sodium ion electrolytes based on organic ionic plastic crystals

 The investigation of solid state sodium ion electrolytes based on Organic Ionic Plastic Crystals were carried out for potential use in the electrochemical devices such as batteries.

A study of phase behavior and conductivity of mixtures of the organic ionic plastic crystal N-methyl-N-methyl-pyrrolidinium dicyanamide with sodium dicyanamide

We report on the thermal, structural and conductivity properties of the organic ionic plastic crystal (OIPC) N-methyl-N-methyl-pyrrolidinium dicyanamide [C1mpyr][N(CN)2] mixed with the sodium salt Na[N(CN)2]. The DSC thermal traces indicate that an isothermal transition, which may be a eutectic melting, occurs at ~ 89 °C, below which all compositions are entirely in the solid phase. At 20 mol% Na[N(CN)2], this transition is the final melt for this mixture, and a new liquidus peak grows beyond 20 mol% Na[N(CN)2]. The III- > II solid-solid phase transition continues to be evident at ~- 2 °C. The microstructure for all the mixtures indicated a phase separated morphology where precipitates can be clearly observed. Most likely, these precipitates consist of a Na-rich second phase. This was also suggested from the vibrational spectroscopy and the 23Na NMR spectra. The lower concentrations of Na[N(CN)2] present complex 23Na MAS spectra, suggesting more than one sodium ion environment is present in these mixtures consistent with complex phase behavior. Unlike other OIPCs where the ionic conductivity usually increases upon doping or mixing in a second component, the conductivity of these mixtures remains relatively constant and above 10- 4 S cm- 1 at ∼ 80 °C, even in the solid state. Such high conductivities suggest these materials may be promising to be used for all solid-state electrochemical devices.

Sodium ion dynamics in a sulfonate based ionomer system studied by 23Na solid-state nuclear magnetic resonance and impedance spectroscopy

A poly(2-acrylamido-2-methyl-1-propane-sulphonate) (PAMPS) ionomer containing both sodium and quaternary ammonium cations functionalised with an ether group, has been characterised in terms of its thermal properties, ionic conductivity and sodium ion dynamics. The ether oxygen was incorporated to reduce the Na+ association with the anionic sulfonate groups tethered to the polymer backbone, thereby promoting ion dissociation and ultimately enhancing the ionic conductivity. This functionalised ammonium cation led to a significant reduction in the ionomer Tg compared to an analogue system without an ether group, resulting in an increase in ionic conductivity of approximately four orders of magnitude. The sodium ion dynamics were probed by 23Na solid-state NMR, which allowed the signals from the dissociated (mobile) and bound Na+ cations to be distinguished. This demonstrates the utility of 23Na solid-state NMR as a probe of sodium dynamics in ionomer systems.

Gelled ionic liquid sodium ion conductors for sodium batteries

Owing to the unique properties of certain Ionic liquids (ILs) as safe and green solvents, as well as the potential of sodium as an alternative to lithium as charge carriers, we investigate gel sodium electrolytes as safe, low cost and high performance materials with sufficient mechanical properties for application in sodium battery technologies. We investigate the effect of formation of two types of gel electrolytes on the properties of IL electrolytes known to support Na/Na⁺ electrochemistry. The ionic conductivity is only slightly decreased by 0.0005 and 0.0002 S cm^-1 in the case of 0.3 and 0.5 M NaNTf2 systems respectively as the physical properties transition from liquid to gel. We observed facile plating and stripping of Na metal around 0 V vs. Na/Na⁺ through the cyclic voltammetry. A wide-temperature range of the gelled IL state, of more than 100 K around room temperature, is achieved in the case of 0.3 and 0.5 M NaNTf2. We conclude that the formation of a gel does not significantly affect the liquid-like ion dynamics in these materials, as further evidenced by DSC and FTIR analysis.

Upregulation of sodium iodide symporter (NIS) protein expression by an innate immunity component: promising potential for targeting radiosensitive retinoblastoma

Retinoblastoma (RB), a malignant tumour of the eye arising from developing retina, is the most frequent primary intraocular malignancy of childhood. Its primary management with chemotherapy involves combination regimen of etoposide, vincristine and carboplatin and intra vitreal chemotherapy using melphalan when vitreous seeds develop. Radiotherapy is another effective mode in treating RB. We recently explored the notion if radiotherapy in RB can be mediated via Sodium Iodide Symporter (NIS), an intrinsic membrane glycoprotein which is a key regulator of iodide access to thyroid gland. Its expression has been exploited successfully for diagnostic imaging and molecular radionuclide-based therapy of thyroid cancer. We determined that NIS is expressed endogenously in RB tumour tissues, and in retinoblastoma cell lines Y79 and Weri-Rb-1, and therefore made an attempt to enhance the endogenously low expression of NIS protein in both Y79 and Weri-Rb-1 cells. Here we report about the potential of bovine lactoferrin (bLf) which is a known chemo preventive and emerging safe anti-cancer bio drug, as well as a natural transcriptional activator of genes, to enhance the endogenous expression of NIS in Y79 and Weri-Rb-1 cells. Real time PCR revealed that both cell lines express mRNA of lactoferrin receptors while flow cytometry and confocal microscopy showed the cells efficiently internalize bLf which upregulates NIS expression. These findings highlight an important step that could be taken towards the development of less harmful approaches for the treatment of RB by employing natural supplement bLf (with its clinically proven safe profile), and warrants further studies in future, focussing on enhancing NIS expression in RB cells and NIS functional assays in these cells.