Moon Sam Shin

Solubility of triclocarban in pure alkanols at different temperatures

Triclocarban solubility in six pure alcohols was determined in the temperature interval from 278.15 to 318.15 K. The experimental solubility data were correlated by the Wilson, the nonrandom two liquid (NRTL) and the universal quasi-chemical (UNIQUAC) models. The data are well fitted with all three models for the six pure alcohols studied here. Also, ab initio geometry optimization of triclocarban was performed using the density functional theory (DFT) based on DMol3 method.

Gemcitabine release behavior of polyurethane matrixes designed for local anti-cancer drug delivery via stent

Gemcitabine is a potent anti-cancer drug, but it has a very short half-life in vivo, necessitating systematic infusion at high doses. We prepared gemcitabine-incorporated polyurethane (GIPU) films with various drug loading levels that can be used as stent coverings for local drug delivery and tumor control around the stent. The release behavior of the film depended on the drug loading level. An initial burst at 4 hours increased from 10 % to 55 % to 75 % of the loading when the Gemzar concentration in the PU film increased from 10 % to 15 % to 20 %, respectively. The amount of the drug released per day reversed the trend, however, at 2 days, and the GIPU film with a lower drug loading released a larger amount of the drug for up to 16 days. GIPU films could be used as stent coverings for the control of unresectable pancreatic or biliary malignant tumors.

Vapor-liquid equilibra for cyclohexane+2-propoxyethanol and cyclohexane+2-butoxyethanol systems

Abstract2-propoxyethanol (C3E1) and 2-butoxyethanol (C4E1) are nonionic surfactants which are a particularly interesting class of substances due to both inter-molecular and intra-molecular association, related to the presence of O and OH in the same molecule. Binary (vapor+liquid) equilibrium data were measured for cyclohexane+2-propoxyethanol and cyclohexane+2-butoxy ethanol systems at temperatures ranging from 303.15 K to 323.15 K at 10 K intervals. A static apparatus was used in this study. Two systems show positive deviation from Raoult’s law and no azeotrope. The experimental data were correlated well with Peng-Robinson-Stryjek-Vera equation of state using Wong-Sandler mixing rule incorporating the non-random-two-liquid model.

A crossover quasi-chemical nonrandom lattice fluid model for pure carbon dioxide and hydrocarbons

Thequasi-chemical nonrandom lattice fluid model is capable of describing thermodynamic properties for complex systems containing associating fluids, polymer, biomolecules and surfactants, but this model fails to reproduce the singular behavior of fluids in the critical region. In this research, we used the quasi-chemical nonrandom lattice fluid model and combined this model with a crossover theory to obtain a crossover quasi-chemical nonrandom lattice fluid model which incorporated the critical scaling laws valid asymptotically close to the critical point and reduced to the original quasi-chemical nonrandom model far from the critical point. The crossover quasi-chemical nonrandom lattice fluid model showed a great improvement in prediction of the volumetric properties and second-order derivative properties near the critical region.