Communication: Unusual structure and transport in ionic liquid-hexane mixtures.

Ionic liquids having a sufficiently amphiphilic cation can dissolve large volume fractions of alkanes, leading to mixtures with intriguing properties on molecular length scales. The trihexyl(tetradecyl)phosphonium cation paired with the bis(trifluoromethylsulfonyl)amide anion provides an ionic liquid that can dissolve large mole fractions of hexane. We present experimental results on mixtures of n-C6D14 with this ionic liquid. High-energy X-ray scattering studies reveal a persistence of the characteristic features of ionic liquid structure even for 80% dilution with n-C6D14. Nuclear magnetic resonance self-diffusion results reveal decidedly non-hydrodynamic behavior where the self-diffusion of the neutral, non-polar n-C6D14 is on average a factor of 21 times faster than for the cation. Exploitation of the unique structural and transport properties of these mixtures may lead to new opportunities for designer solvents for enhanced chemical reactivity and interface science.

Ionic Liquid-Solute Interactions Studied by 2D NOE NMR Spectroscopy.

Intermolecular interactions between a Ru(2+)(bpy)3 solute and the anions and cations of four different ionic liquids (ILs) are investigated by 2D NMR nuclear Overhauser effect (NOE) techniques, including {(1)H-(19)F} HOESY and {(1)H-(1)H} ROESY. Four ILs are studied, each having the same bis(trifluoromethylsulfonyl)amide anion in common. Two of the ILs have aliphatic 1-alkyl-1-methylpyrrolidinium cations, while the other two ILs have aromatic 1-alkyl-3-methylimidazolium cations. ILs with both shorter (butyl) and longer (octyl or decyl) cationic alkyl substituents are studied. NOE NMR results suggest that the local environment of IL anions and cations near the Ru(2+)(bpy)3 solute is rather different from the bulk IL structure. The solute-anion and solute-cation interactions are significantly different both for ILs with short vs long alkyl tails and for ILs with aliphatic vs aromatic cation polar head groups. In particular, the solute-anion interactions are observed to be about 3 times stronger for the cations with shorter alkyl tails relative to the ILs with longer alkyl tails. The Ru(2+)(bpy)3 solute interacts with both the polar head and the nonpolar tail groups of the 1-butyl-1-methylpyrrolidinium cation but only with the nonpolar tail groups of the 1-decyl-1-methylpyrrolidinium cation.

Diffusion Coefficients from (13)C PGSE NMR Measurements-Fluorine-Free Ionic Liquids with the DCTA(-) Anion.

Pulsed-field gradient spin-echo (PGSE) NMR is a widely used method for the determination of molecular and ionic self-diffusion coefficients. The analysis has thus far been limited largely to (1)H, (7)Li, (19)F, and (31)P nuclei. This limitation handicaps the analysis of materials without these nuclei or for which these nuclei are insufficient for complete characterization. This is demonstrated with a class of ionic liquids (or ILs) based on the nonfluorinated anion 4,5-dicarbonitrile-1,2,3-triazole (DCTA(-)). It is demonstrated here that (13)C-PGSE NMR can be used to both verify the diffusion coefficients obtained from other nuclei, as well as characterize materials that lack commonly scrutinized nuclei - all without the need for specialized NMR methods.

A Study of the Effect of Heat-Treatment on the Morphology of Nafion Ionomer Dispersion for Use in the Passive Direct Methanol Fuel Cell (DMFC).

Aggregation in heat-treated Nafion ionomer dispersion and 117 membrane are investigated by 1H and 19F Nuclear Magnetic Resonance (NMR) spectra, spin-lattice relaxation time, and self-diffusion coefficient measurements. Results demonstrate that heat-treatment affects the average Nafion particle size in aqueous dispersions. Measurements on heat-treated Nafion 117 membrane show changes in the 1H isotropic chemical shift and no significant changes in ionic conductivity. Scanning electron microscopy (SEM) analysis of prepared cathode catalyst layer containing the heat-treated dispersions reveals that the surface of the electrode with the catalyst ink that has been pretreated at ca. 80 °C exhibits a compact and uniform morphology. The decrease of Nafion ionomer's size results in better contact between catalyst particles and electrolyte, higher electrochemically active surface area, as well as significant improvement in the DMFC's performance, as verified by electrochemical analysis and single cell evaluation.

Clinical implications of expression of ETS-1 related to angiogenesis in metastatic lesions of ovarian cancers.

OBJECTIVE: ETS-1 has been identified as a proto-oncogene and a transcription factor for tumor angiogenesis, which is essential for the growth, invasion and metastasis of solid tumors. The aim is to investigate the clinical implications of ETS-1 expression in peritoneal metastatic lesions of ovarian cancers. METHODS: In primary tumors and peritoneal metastatic lesions from 30 patients with stage III ovarian cancers, ETS-1 histoscores and ets-1 mRNA levels were determined by immunohistochemistry and competitive RT-PCR-Southern blot analysis using recombinant RNA, respectively. RESULTS: Immunohistochemical staining revealed that ETS-1 was expressed in the cancer cells and vascular endothelial cells. ETS-1 histoscores in the endothelial cells and ets-1 mRNA levels were significantly (p < 0.05) increased in 20 of 30 peritoneal metastatic lesions of ovarian cancers. There was a significant correlation between microvessel counts (MVCs) and ETS-1 histoscores in the endothelial cells (p < 0.001) and between MVCs and ets-1 mRNA levels in the primary tumor and the peritoneal metastatic lesion of ovarian cancers (p < 0.001). Furthermore, the 24-month survival rate of patients with significantly increased ets-1 mRNA level (2/20, 10%) was significantly (p < 0.01) lower than that of patients with no change in the level (6/10, 60%) from the primary tumor to the peritoneal metastatic lesion. CONCLUSIONS: ETS-1 might be associated with peritoneal metastasis dominantly as an angiogenic mediator and additionally as an oncogene product to activate tumor invasion in ovarian cancers.

Clinical implications of expression of ETS-1 in relation to angiogenesis in ovarian cancers.

ETS-1 has been identified as a transcription factor involved in tumor angiogenesis, which is essential for the growth, invasion, and metastasis of solid tumors. This result prompted us to study whether ETS-1 works as an angiogenic mediator in ovarian cancers. Immunohistochemical staining revealed that ETS-1 was expressed in vascular endothelial cells and in cancer cells of ovarian cancers. There was a significant correlation between microvessel counts and both ETS-1 histoscores and ets-1 mRNA levels in ovarian cancers. Both ETS-1 histoscores and ets-1 mRNA levels increased with the progression of ovarian cancers. Furthermore, the 24-month survival rate of 30 patients with high ets-1 (high ETS-1 histoscores and high ets-1 mRNA levels) was 30%, while that of 30 other patients with low ets-1 (low ETS-1 histoscores and ets-1 mRNA levels) was 70%. There was a significant difference between the 24-month survival rates of the 30 patients with high ets-1 and the 30 with low ets-1. This indicates that ETS-1 might act as an angiogenic mediator in, and be a prognostic factor for, ovarian cancers.

Expression of ETS-1 related to angiogenesis in uterine endometrium during the menstrual cycle.

ETS-1 has been identified as a transcription factor for angiogenesis, which is essential for the development and growth of the uterine endometrium. This characteristic prompted us to study whether ETS-1 functions as an angiogenic mediator in uterine endometrium. Immunohistochemical staining revealed that the localization of ETS-1 was similar to that of vascular endothelial cells. There was a significant correlation between microvessel counts and both ETS-1 histoscores and ets-1 mRNA levels in uterine endometrium. The ETS-1 histoscores and ets-1 mRNA levels increased in the proliferative phase, reached a peak during peri-ovulation and decreased in the secretory phase. Furthermore, the ETS-1 histoscores and ets-1 mRNA levels correlated with vascular endothelial growth factor (VEGF) levels in the proliferative phase. This indicates that ETS-1 might be an angiogenic mediator in uterine endometrium linked to VEGF in the proliferative phase.