Iodinated Cyanoacrylate-based Novel Liquid Embolic Compositions with Inherent Radiopacity for Endovascular Embolization.

Endovascular embolization is a promising therapeutic approach broadening its application area due to its minimal invasiveness and short operation time, wherein lesional blood vessels are occluded with liquid embolic agents under X-ray imaging guidance. Histoacryl and its composition with Lipiodol are one of the most widely used liquid embolic agents, however, Histoacryl has critical limitations such as lack of innate X-ray visibility and strong adhesion to microcatheter. In this study, three different iodinated cyanoacrylates are newly synthesized as alternatives to Histoacryl and employed to develop liquid embolic compositions. Among them, 4-iodobutyl 2-cyanoacrylate (IBCA) was most preferable with high iodine content (730 mgI/mL) and fast polymerization. The IBCA-based embolic compositions containing ethyl oleate and acetic acid showed moderate viscosity and reduced catheter adhesiveness (∼ 0.80 N), and their polymerization time was freely controllable from 2 to 15 s. In the embolization test with rabbit models, the renal artery was successfully occluded by IBCA-based embolic compositions without vascular recanalization or non-target embolization for 4 w. Their embolic effect was further evaluated using swine models, demonstrating the practical applicability in the clinic. In conclusion, IBCA and its compositions are determined to have great potential as novel liquid embolic agents. This article is protected by copyright. All rights reserved.

Remote Plasma-Induced Synthesis of Self-Assembled MoS2/Carbon Nanowall Nanocomposites and Their Application as High-Performance Active Materials for Supercapacitors.

The objective of this study is to investigate the synthesis and influence of MoS2 on carbon nanowalls (CNWs) as supercapacitor electrodes. The synthesis of MoS2 on CNW was achieved by the introduction of hydrogen remote plasma from ammonium tetrathiomolybdate (ATTM) without deterioration of the CNWs. The topographical surface structures and electrochemical characteristics of the MoS2-CNW composite electrodes were explored using two ATTM-dispersed organic solvents-acetonitrile and dimethylformamide (DMF). In this study, CNW and MoS2 were synthesized using an electron cyclotron resonance plasma. However, hydrogen radicals, which transform ATTM into MoS2, were provided in the form of a remote plasma source. The electrochemical performances of MoS2-CNW hybrid electrodes with various morphologies-depending on the solvent and ATTM concentration-were evaluated using a three-electrode system. The results revealed that the morphology of the synthesized MoS2 was influenced by the organic solvent used and affected both the electrochemical performance and topographical characteristics. Notably, considerable enhancement of the specific capacitance was observed for the MoS2 with open top edges synthesized from DMF. These encouraging results may motivate additional research on hybrid supercapacitor electrodes and the rapid synthesis of MoS2 and other transition metal dichalcogenides.

Characteristics of Plasma Flow for Microwave Plasma Assisted Aerosol Deposition.

To validate the possibility of the developed microwave plasma source with a novel structure for plasma aerosol deposition, the characteristics of the plasma flow velocity generated from the microwave plasma source were investigated by a Mach probe with pressure variation. Simulation with the turbulent model was introduced to deduce calibration factor of the Mach probe and to compare experimental measurements for analyses of collisional plasma conditions. The results show calibration factor does not seem to be a constant parameter and highly dependent on the collision parameter. The measured plasma flow velocity, which witnessed fluctuations produced by a shock flow, was between 400 and 700 m/s. The optimized conditions for microwave plasma assisted aerosol deposition were derived by the results obtained from analyses of the parameters of microwave plasma jet. Under the optimized conditions, Y2O3 coatings deposited on an aluminum substrate were investigated using scanning electron microscope. The results presented in this study show the microwave plasma assisted aerosol deposition with the developed microwave plasma source is highly feasible for thick films with >50 µm.

Development of plasma assisted thermal vapor deposition technique for high-quality thin film.

The novel technique of Plasma-Assisted Vapor Deposition (PAVD) is developed as a new deposition method for thin metal films. The PAVD technique yields a high-quality thin film without any heating of the substrate because evaporated particles acquire energy from plasma that is confined to the inside of the evaporation source. Experiments of silver thin film deposition have been carried out in conditions of pressure lower than 10-3 Pa. Pure silver plasma generation is verified by the measurement of the Ag-I peak using optical emission spectroscopy. A four point probe and a UV-VIS spectrophotometer are used to measure the electrical and optical properties of the silver film that is deposited by PAVD. For an ultra-thin silver film with a thickness of 6.5 nm, we obtain the result of high-performance silver film properties, including a sheet resistance <20 Ω sq-1 and a visible-range transmittance >75%. The PAVD-film properties show a low sheet resistance of 30% and the same transmittance with conventional thermal evaporation film. In the PAVD source, highly energetic particles and UV from plasma do not reach the substrate because the plasma is completely shielded by the optimized nozzle of the crucible. This new PAVD technique could be a realistic solution to improve the qualities of transparent electrodes for organic light emission device fabrication without causing damage to the organic layers.