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Volume 23 (1998)
- Issue 6 Pages 280-
- Issue 5 Pages 226-
- Issue 4 Pages 156-
- Issue 3 Pages 104-
- Issue 2 Pages 50-
- Issue 1 Pages 2-
Volume 23, Issue 3
Displaying 1-7 of 7 articles from this issue
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Hironobu Kunieda, Yoko Yamaguchi1998 Volume 23 Issue 3 Pages 104-111
Published: May 01, 1998
Released on J-STAGE: August 11, 2010
JOURNAL FREE ACCESSWhen the volume fraction of emulsion droplets exceed 0.74 as a closest-packing ratio for sphere, the droplets become the polyhedral shape rather than a spherical one. These emulsions are called HIPRE or highly concentrated emulsions. Since the HIPRE with the extreme high volume fraction of the dispersed phase shows visco-elastic and sometimes translucent, they are also refered to as “gel-emulsions”.
The type of gel emulsion formed in a given system depends mainly on the hydrophile-lipophile balance (HLB) of the surfactant. We describe the correlations between the nature of surfactant (HLB) and the emulsions types in a polyoxyethylene-type nonionic surfactant systems. The structure of the contineous phase in HIPREs is also mentioned.
The stability of W/O type HIPREs is enhanced by the addition of inorganic salts or some amphiliphiles such as monoglycerides and lecitions which produce a bilayer in water.
The two new techiniques to produce HIPREs are over-viewed.View full abstractDownload PDF (2554K) -
Hideo Nakajima, Tohru Okamoto1998 Volume 23 Issue 3 Pages 112-119
Published: May 01, 1998
Released on J-STAGE: August 11, 2010
JOURNAL FREE ACCESSIt is known that O/W cream is solidified with the network structure of liquid crystals formed by fatty alcohols and surfactants in water phase. The liquid crystals are responsible for rich feeling of creams, and provide the skin moisturizing effect of creams. In this review, we discussed about the liquid crystals formed by surfactants and fatty alcohols, and emulsions using them from the viewpoint of cosmetics. At first, the microscopic structure of emulsion having liquid crystal is summarized. In the second, new type formulations utilizing liquid crystals, which have extremely low viscosity and transparent appearance, were referred.View full abstractDownload PDF (3111K) -
Hiroyuki Saito1998 Volume 23 Issue 3 Pages 120-125
Published: May 01, 1998
Released on J-STAGE: August 11, 2010
JOURNAL FREE ACCESSPlasma triglyceride-rich lipoproteins, chylomicrons and VLDL, vary in lipid composition during their metabolism. Using lipid emulsions of defined composition as model particles, we investigated the effects of the lipid composition on the surface and core structures and the metabolism of the emulsion particles. Surface cholesterol significantly facilitated the removal of triglyceride-phosphatidylcholine emulsions from plasma after intravenous injection to rats, presumably due to the change in the ratio of bound apolipoprotein E (apoE) to Cs at the emulsion surface. In contrast, sphingomyelin, the second most abundant phospholipid in lipoproteins, delayed the emulsion clearance and showed the strong inhibition of the apoE binding and lipolysis by lipoprotein lipase. These changes in the emulsion metabolism caused by cholesterol and sphingomyelin are thought to result from the modification of the emulsion surface structures. On the other hand, cholestery oleate, major component of core lipids in LDL, was shown to retard the emulsion clearance by means of the decrease in the bound apoE content, which was closely correlated with the mobility of core lipids rather than the surface structure. These results indicate that not only the surface structure but also the core mobility modulate the emulsion metabolism through the alteration in the binding behavior of apolipoproteins.View full abstractDownload PDF (819K) -
Junzo Seki1998 Volume 23 Issue 3 Pages 126-131
Published: May 01, 1998
Released on J-STAGE: August 11, 2010
JOURNAL FREE ACCESSConventional lipid emulsions (LM), with a mean diameter of 0.2-0.3μm and consisting of soybean oil and lecithin, are used for parenteral carriers for site-specific drug delivery as well as for parenteral nutrition. Plasma lipoproteins are well known as endogenous colloidal lipid particles which have physiological roles to deliver many lipids to specific sites in the body and as a potential carrier of drugs. If a lipophilic drug joins with plasma lipoproteins, the amount of the drug entering tissues may vary widely because each lipoprotein has different metabolic fate. One might also expect that lipid emulsions with different size and/or compositions may show different characteristics of drug carriers. For example, a small lipid emulsion of particles, Lipid Nano-Sphere (LNS®), with a mean diameter of 25-50nm, are characterized by lower uptake by the liver, prolonged plasma half-lives of drugs, and good distribution into sites of inflammation, tumor, etc. as compared with LM. The difference between them is explained by the affinities to apolipoprotein C-II and E. LM has high affinity to these apolipoproteins and rapidly enters into the liver like chylomicrons. In the both emulsions, they are in dynamic pathways of lipoprotein metabolism in the circulation. Several types of lipid emulsion with different properties as drug carrier are under investigations.View full abstractDownload PDF (921K) -
Kousuke Mori, Haruhiko Ohya, Svetlana I. Semenova, Toshinori Fujimoto, ...1998 Volume 23 Issue 3 Pages 132-139
Published: May 01, 1998
Released on J-STAGE: August 11, 2010
JOURNAL FREE ACCESSA partial differential diffusion equation for dialysis phenomenon is derived considering the effect of osmosis flux jw of which the initial value jw0 was observed very high and decreased exponentially with time toward jw∞ with a time constant τ. Numerical integration of the equation with time, gives dialysis curve which shifts toward right with the increase of pushing back effect (jw0/jw∞) and prolonging effect τ. Therefore, the intercept on T(=tD/l2)-axis, TL, for the asymptotic line of dialysis curve which is usually 0.17 for gas separation membranes (special case for no osmosis), increases with the increase of the both effects, for example TL=1.0 for jw0/jw∞=10 and τD/l2=0.5.
With cellulose acetate symmetric membranes, it was observed that the shape of dialysis curve changed from convex for the new membrane to concave at the 2nd, 3rd and 4th run. With the dialysis curve of 4th run and the measured osmosis flux, the best fit combination of distribution coefficient Kc and diffusivity Dc was obtained for the minimum error squared, as Kc=0.05 and Dc=2.2×10-14[m2·s-1].
The diffusion coefficient De and distribution coefficient Ke were measured as De=2.5×10-14[m2·s-1] and Ke=0.05, respectively which agree quite well with the calculated Dc and Kc.View full abstractDownload PDF (944K) -
Kenichi Ushikoshi, Kanji Matsumoto1998 Volume 23 Issue 3 Pages 140-147
Published: May 01, 1998
Released on J-STAGE: August 11, 2010
JOURNAL FREE ACCESSSeveral types of pretreatment system have been tested and investigated to treat salty lake water by reverse osmosis system. (1) A sludge blanket type clarifier followed by a sand filter and an activated carbon filter could not yield product water which complied with inlet water quality conditions for reverse osmosis systems. A precoated sand filter instead of the simple anthracite filter produced slightly better product water, but it could not satisfy the inlet water quality conditions. An additional injection of a small amount of coagulant ahead of the sand filter improved product water quality to the level where spiral wound type reverse osmosis system could be applicable. (2) An inline coagulation method using a dual media filter followed by an activated carbon filter gave an outstanding result comparing to the former processes producing very high quality water which covers the conditions of inlet water quality for spiral wound type and hollow fine fiber type reverse osmosis system as well. The tests suggested that an excessive long time retention of flocs in the process gave the worse product water quality. The PN value was used instead of SDI index to measure levels of very low suspended matter.View full abstractDownload PDF (1160K) -
Tsunemichi Kawa, Tetsuji Koyama, Hidetoshi Urakawa, Shigeru Yanagihara ...1998 Volume 23 Issue 3 Pages 148-152
Published: May 01, 1998
Released on J-STAGE: August 11, 2010
JOURNAL FREE ACCESS“SOKKEN” Model SCF-NM-_??_s, nicke mesh filters, are porous thin metal membranes produced by a combined technology of photo-resist processing and highly advanced nickel plating, manufactured by Dainippon Printing and standardized by Tsukasa Sokken. We specified that the filter should have a diameter of 13mm, a thickness of 11μm, pore diameters of 2.9 to 5.4μm, the inter-pore distance of 35μm, and a pore number of about 55, 600. We determined the effective pore diameter of the filters with an accuracy of the order of 0.01μm, using pressure-flow rate relationships of airflow.View full abstractDownload PDF (3223K)
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