• Bulletin of the Korean Chemical Society
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• v.12 no.5
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• pp.474-477
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• 1991

The preferential transport phenomena of neutral cation-anion moieties in neutral macrocycle-facilitated emulsion liquid membrane were described in this study. Emulsion membrane systems consisting of (1) aqueous source phase containing 0.001 M M($NO_3$)$_2(M=Mn^{2+},\;Co^{2+},\;Ni^{2+},\;Cu^{2+},\;Zn^{2+},\;Sr^{2+},\;Cd^{2+},\;and\;Pb^{2+})$ (2) a toluene membrane containing 0.01 M ligand $(DBN_3O_2$, DA18C6, DT18C6, TT18C6, HT18C6) and the surfactant span 80 (sorbitan monooleate) (3% v/v) and (3) an aqueous receiving phase containing $Na_2S_2O_3$ or $NaNO_3$ were studied with respect to the disappearence of transition metal ions from the source phase as a function of time. Cation transports for various two component or three component equimolar mixture of transition metal and $Cu^{2+}$ in a emulsion membrane system incorporating macrocyclic ligand (HT18C6) as carrier were determinded. $Cu^{2+}$ was transported higher rates than the other $M^{2+}$ in the mixture solution. Equilibrium constants for cation-source phase co-anion, cation macrocycle and cation-receiving phase reagent interaction are examined as parameters for the prediction of cation transport selectivities.

• Journal of the Korean Applied Science and Technology
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• v.34 no.1
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• pp.50-57
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• 2017

Zinc oxide is, one of metal oxide semiconductor, harmless to human and environment-friendly. It has excellent chemical and thermal stability properties. Wurtzite-zinc oxide is a large band gap energy of 3.37 eV and high exciton binding energy of 60 meV. It can be applied to various fields, such as solar cells, degradation of the dye waste, the gas sensor. The photocatalytic activity of zinc oxide is varied according to the particle shape and change of crystallinity. Therefore, It is very important to specify the additives and the experimental variables. In this study, the zinc oxide were synthesized by using a microwave assisted hydrothermal synthesis. The precursor was used as the zinc nitrate, the pH value was controlled as 11 by NaOH. Surfactants are the ethanolamine, cetyltrimethylammonium bromide, sodium dodecyl sulfate, sorbitan monooleate was added by changing the concentration. The composite particles had the shape of a star-like, curcular cone, seed shape, flake-sphere. Physical and chemical properties of the obtained zinc oxide was characterized using x-ray diffractometer, field emission scanning electron microscopy, thermogravimetric analysis and optical properties was characterized using UV-visible spectroscopy, photoluminescence and raman spectroscopy.

• Journal of Life Science
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• v.31 no.5
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• pp.502-510
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• 2021

The objective of this study was to develop a novel ticagrelor-loaded self-nanoemulsifying drug delivery system with an enhanced solubility and dissolution rate. Numerous oils and surfactants were screened, then medium chain triglyceride (MCT) oil and the surfactants polyoxyethylene sorbitan monooleate (Tween 80) and Labrafil M1944CS were selected for the preparation of the ticagrelor-loaded self-nanoemulsifying drug delivery system. A pseudo-ternary phase diagram was constructed to detect the nanoemulsion region. Of the various formulations tested, the liquid SNEDDS, composed of MCT (oil), Tween 80 (surfactant), and Labrafil M1944CS (cosurfactant) at a weight ratio of 20/70/10 produced the smallest emulsion droplet size (around 20.56±0.70 nm). Then, particle size, polydispersity, and zeta potential were measured using drugs containing liquid SNEDDS. The selected ticagrelor-loaded liquid SNEDDS was spray-dried to convert it into a ticagrelor-loaded solid SNEDDS with a suitable inert carrier, such as silicon dioxide, calcium silicate, or magnesium aluminometasilicate. The solid SNEDDS was characterized by scanning electron microscopy, transmission electron microscopy, and in vitro dissolution studies. SEM, PXRD, and DSC results suggested that amorphous ticagrelor was present in the solid SNEDDS. Also, the solid SNEDDS significantly increased the dissolution rate of ticagrelor. In particular, the emulsion particle size and the polydispersity index of the solid SNEDDS using silicon dioxide (SS1) as a carrier was the smallest among the evaluated solid SNEDDS, and the flowability and compressibility result of the SS1 was the most suitable for the manufacturing of solid dosage forms. Therefore, solid SNEDDS using silicon dioxide (SS1) could be a potential nano-sized drug delivery system for the poorly water-soluble drug ticagrelor.