• Applied Biological Chemistry
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• v.35 no.2
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• pp.76-81
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• 1992

The technicals of KC-7079, isoprothiolane, perfluidone and tricyclazole were granulated with a mixture of inorganic carrier and oil-soluble binder, that is, stearly alcohol or ethyl cellulose. The concentration of the released active ingredient from the granules was analyzed at several days intervals after immersion of these granules in water at $25^{\circ}C$. At the content of stearyl alcohol less than $80g\;kg^{-1}$, the granule kneaded with stearyl alcohol mixture and water disintegrated in water. But the granule kneaded with methanol disintegrated in water at the content of stearyl alcohol less than $30g\;kg^{-1}$. The less the KC-7079-stearyl alcohol granule disintegrated, the slower the release rate of KC-7079 was. No matter how was increased the stearyl alcohol content, the release rate of KC-7079 granule which did not disintegrate was not significantly changed. The sustained releasing effect of the granules was little in the other three pesticides of which the water solubility was higher than of KC-7079(21 ppm). The granule made of ethyl cellulose did not disintegrate even at $5g\;kg^{-1}$ of ethyl cellulose. With the increase of ethyl cellulose content and the decrease of active ingredient in the granules, the sustaining effect of the granules on releasing acitive ingredient was increased. The lower the water solubility of pesticide was, the release rate tended to be sustained except perfluidone.

• Journal of Pharmaceutical Investigation
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• v.24 no.3
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• pp.167-176
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• 1994

The microcapsules of amoxicillin using stearyl alcohol and polyethyleneglycol 8000 (PEG 8000) were prepared by a emulsion melted-cooled process in water phase. The size distribution, dissolution test, observation with SEM and in vivo test were investigated. The microcapsules obtained were spherical, uniform and free flowing particles. The release of drug from microcapsule was increased in proportional to the content of PEG 8000. As the PEG 8000 content increased, the particle size of microcapsule was decreased. Sanning electron micrograph study revealed that microcapsules had comparatively rough surfaces as drug content was increased. The $AUC_{0-12}$ after administration of amoxicillin microcapsules was more increased 40% as compared with the AUC after administration of amoxicillin powder in rabbits.

• YAKHAK HOEJI
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• v.39 no.5
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• pp.487-494
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• 1995

Solid lipid microspheres (SLMs) were prepared using various lipids and solidifying agents, in order to enhance the gastrointestinal absorption of Cyclosporine A (Cs A) which is a practically water-insoluble drug with low systemic bioavailability. Egg lecithin and HCO-60 (polyoxyethylated 60 mol, hydrogenated castor oil) were used as lipids. Stearic acid and stearyl alcohol were used as solidifying agents. Emulsion concentrates containing Cs A were prepared by mixing the melted lipid and solidifying agent with water, employing bile salts as a cosurfactant. SLMs were obtained by dispersing the warm emulsion concentrate in cold distilled water under mechanical stirring, followed by freeze drying. Physical characteristics of each SLM were investigated by particle size analysis, optical microscopy and scanning electron microscopy. Mean particle size of SLMs was in the range of 30 to 40.mu.m. The SLMs were in good appearance with spherical shape before freeze drying, but were deformed partially after freeze drying. Drug loading efficiencies of SLMs were observed as high as 80 to 90% in average. The systemic bioavailability of Cs A from different SLM formula was investigated in rats following oral administration. Cs A in whole blood was extracted and assayed by HPLC. SLMs revealed the higher bioavailabilities than the standard formula based on the marketed product. SLMs might have several advantages over standard formula for enhanced gastrointestinal absorption, controlled release properties, high loading capacity of the water-insoluble drug, and feasibility of solid dosage forms with better stability in storage.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.35 no.2
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• pp.103-110
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• 2009

The objective of this study is to analyze the influences of fatty alcohols and fatty acids on rheological properties of oil in water (O/W) emulsions using viscosity and rheograms. As the chain length of fatty alcohols and fatty acids lengthened, the viscosity of emulsions was increased. The influence of fatty alcohols on viscosity enhancement was stronger than that of fatty acids. Both stearyl alcohol and cetearyl alcohol, which have carbon chain length similar to lipophilic portion of surfactant used in emulsion preparation, had showed the best increase in viscosity of O/W emulsions. O/W emulsions prepared with fatty alcohols and fatty acids were pseudo-plastic fluid and they showed shear thinning behaviour like as the common cosmetic emulsions. O/W emulsions prepared with cetyl alcohol, cetearyl alcohol and stearyl alcohol were thixotropic fluids and thixotropy increased with an increase in the concentration of fatty alcohols and fatty acids. Also O/W emulsions prepared with fatty alcohols were more thixotropic than those prepared with fatty acids. For the sake of viscosity increase related to O/W emulsions stability and spreadability enhancement related to payoff, it is thought that fatty alcohols are more useful than fatty acids in the O/W emulsions as the emulsion stabilizer.

• KIEE International Transactions on Electrophysics and Applications
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• v.4C no.1
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• pp.26-30
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• 2004

Orientation control of a polyoxometalate (POM) nanoparticle in its two-dimensional arrangement was attempted by Langmuir-Blodgett (LB) technique. For their uniorientation, two carboxyl groups were introduced on one side of the POM particle, and hydrophobic long chains were attached by esterification with the carboxyl groups (C18-POM). The C18-POM layer spread on water surface showed stability against surface pressure up to 60 mN/m. The pattern of the C18-POM isotherm was quite different from stearyl alcohol (C18-OH), while the POM itself did not show any development of surface pressure on water surface. The AFM images of C18-POM LB films showed some microcrystalline structures that were noticed as dot structures by Brewster angle microscopy. The microimages for C18-POM did not completely spread out as a monolayer on the water surface. The XPS spectra indicated the presence of POM structures and stearyl ester bonds formed from about 65% of the total carboxyls. The XRD spectra showed that the unioriented POMs were not positioned with the same lattice distance but rather in a wavy surface state.

• Journal of Adhesion and Interface
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• v.15 no.4
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• pp.151-160
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• 2014

A series of terpolymers based on stearyl methacrylate (SMA), n-methyol acrylamide (n-MAM), and 2-(perfluorooctyl) ethyl acrylate (PFOEA) were synthesized by changing PFOEA contents up to 8 wt% in order to obtain optimal water-repellent properties. In addition, various contents of m-isopropenyl-${\alpha}$,${\alpha}^{\prime}$-dimethylbenzyl isocyanate (TMI) from 1 to 4 wt% were added to the above terpolymers with 4 wt% of PFOEA content. The emulsion polymerization was carried out using tridecyl alcohol (EO)7 (TDA-7) as a nonionic surfactant, alkyl dimethyl amine derivatives (ADAD) as a cationic surfactant, and 2,2'-azobis(2-amidinopropane dihydrochoride) (AAPDL) as an initiator. The synthesized copolymers were characterized by FT-IR spectroscopies, contact angle, surface energy, and water-repellency. Surface and thermal properties were analyzed by SEM, TGA, and DSC. It was found that water repellency increased with increasing the contents of PFOEA and TMI.

• Archives of Pharmacal Research
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• v.11 no.3
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• pp.185-196
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• 1988

The inflence of hydrophilic vehicles on percutaneous absorption rate of griseofulvin was studied using intact skin of full thickness of hairless rat. The in vitro absorption rates were used as the characteristics for deciding the optimum formula of ointment vehicles. The optimum formula of vehicle compositions for maximum absorption rate was obtained from the polynomial regression equation and the two graphical techniques, contour graph and partial derivative graph. It was composed of sodium lauryl sulfate (1.65 W /W%), white petrolatum (16.5 W /W%), propylene glycol (12.0 W /W%), and stearyl alcohol (19.6W /W%). The experimental value obtained from the optimum formula and the prediction value were 33.99 and 33.87 ${\mu}g/\sqrt{min}$, respectively. From these results, it was believed that optimum formula for semisolid dosage forms could be obtained from the application of the optimization technique used in this study.

• Biotechnology and Bioprocess Engineering:BBE
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• v.2 no.2
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• pp.109-112
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• 1997

Morphology of carbonate crystals grown on the surface of artificial cell membranes was controlled by changing the interfacial chemistry. For octadecyltriethoxysilane (OTE) films with terminal methyl groups interacting little with an aqueous calcium carbonate solution calcite (104) crystals were formed. Polymerized pentacosadiynoic acid (PDA) films with terminal carboxylic acid groups induced deposition of calcite (012) crystals aligned along with each other within a polymer domain. On the other hand, stearyl alcohol (StOH) films with terminal hydroxyl groups induced deposition of aragonite crystals. When PDA was mixed with StOH, the 8:1 PDA:StOH (molar ratio) film produced dominating calcite (012) crystals without any crystal alignment, and the 4:1 mixture film produced minor calcite (012) crystals and major aragonite crystals. For the 2:1, 1:1, 1:2, and 1:4 mixture films, aragonite crystals were dominating. Hence, it is found that the chemical composition at the interface plays a very important role in controlling the morphology of deposited carbonate crystals.

• Reproductive and Developmental Biology
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• v.34 no.3
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• pp.117-122
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• 2010

To search the potent pig pheromonal odorants through receptor-based approach methods, molecular dockings between 680 Flavomets as substrate molecule and pig odorants binding proteins OBP (1HQP) and PBP (1GM6) as receptor, and QSPR (quantitative structure-property relationship) analyses from physico-chemical parameters of Flavomets and their docking scores (DS) were performed and discussed quantitatively. From the basis on the findings, the optimal value $(MSA)_{opt.}=407.595\;{\AA}^2$ of MSA (molecular surface area; ${\AA}$), and RB (number of rotational bond) had the Flavomets will be able to increase DS. Therefore, it is expected that the stearyl alcohol from DS and H-bond type between substrate and receptor would be shows the character as potent pig pheromonal odorant.

• Journal of Pharmaceutical Investigation
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• v.29 no.4
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• pp.279-285
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• 1999

Retinoids in anti-wrinkle cosmetics are widely used for the treatment of the photoaging skin these days, but very unstable in the presence of water. Multilamellar liquid crystal vesicles consisted of $poly(oxyethylene)_{15}oleyl$ ether $(POE_{15}OE)$ or $poly(oxyethylene)_{15}stearyl$ ether $(POE_{15}SE)$, cetostearyl alcohol (CSA) and cholesterol or oils were prepared to increase the stability of retinyl acetate or retinyl palmitate. $POE_{15}SE-CSA-Water$ systems were more unstable than $POE_{15}SE-CSA-Water$ systems due to the bended structure of oleyl groups. For the modification of vesicles, cholesterol was added. The enthalpy values were decreased reaching to zero and the water permeability of systems was decreased, but the stabilizaton of retinyl acetate was not greatly improved. The stability of retinyl acetate may depend on its location in the structure. Various oils were added for further stabilization and isopropyl myristate was most effective. In practice, retinyl palmitate showed better stability in the same vesicle than retinyl acetate, and the improved vesicles could be used for the anti-wrinkle cosmetics