Poly-L-arginine-Hydroxyapatite Nanoparticle Complexes Translocate Through Lipidbilayer Membranes

Certain molecules, which are able to directly translocate across phospholipid bilayer membranes (cell or endosormal membrane), can be useful as carriers (vectors) for drags (especially polymeric drags). We have studied the translocationability of the hydroxyapatite nanoparticle-poly-L-arginine complex through the negatively charged phospholipid bilayer membranes by using several instruments. It was confirmed by means of a confocal laser scanning microscopy (CLSM) not only the fact that the complex can translocate through the membranes but also the fact that the complexes were still retained in the inner water layer of the liposome even after the translocation.


Formation of Poly-L-Arginine - Hydroxyapatite Nanoparticle Complexes and Interactions between Complexes and Lipidbilayer Membranes


Solubility of monoalkyl phosphate in water in the presence of arginine and Triton, and solubilization of methyl yellow through the mixed micelle

モノアルキルリン酸およびヂセチルリン酸は水には殆ど溶解しない．70℃の高温でTriton-XあるいはTriton-Nの存在で前者はやや溶解度が上がるが，後者はそれでも殆ど溶解しないことを指摘した．アルギニンが存在すると室温でも溶解することを確認したのち，モノアルキルリン酸ーTXあるいはTN-アルギニン混合ミセルによるメチルイエロウの可溶化量を測定した．モノアルキルリン酸の溶解機構を検討し，KOHで中和する場合とアルギニンで中和する場合の相違点について考察した．


Effects of ionic surfactants on the adsorption of bovine serum albumin to the surface of hydroxyapatite


Effects of Phosphate Ions on the Polypeptide-Liposome Membrane Interaction


Polyethyleneimine can permeate through a lipid bilayer of a giant liposome

Journal of Japanese Medical Society for Biological Interface


Effect of Dodecyltrimethylammonium Chloride on the Adsorption of Bovine Serum Albumin to the Surface of Hydroxyapatite


Effect of polyvinylpyrrolidone and sodium lauruyl isethionate on kaolinite suspension in an aqueous phase

Suspension of concentrated kaolinite (20 g/30 ml-medium) in the presence of polyvinylpyrrolidone (PVP) and sodium lauroyl isethionate (SLI) was allowed to evaluate its degree of dispersion based on their rheological studies. Flow curves at low shear rate, measured by means of cone-plate method, showed a non-Newtonian flow. Plastic viscosity and Bingham yield value were derived from the flow curves. Relative viscosity, effective volume fraction and void fraction of secondary particle were also obtained. Results of dispersity and fluidity of the suspension were explained. PVP acted as a flocculant at a concentration lower than 0.1% but as a dispersant at a higher concentration. The presence of SLI could decrease both the Bingham yield value and suspension viscosity. Cooperative and competitive effects of PVP and SLI were found. Results indicated that SLI enhanced the degree of dispersion of kaolinite when PVP was less than 0.1%. The suspension, however, showed a maximum flocculation (i.e., aggregation) at 4 mM SLI when the concentration of PVP was higher than 0.1%.


Preparation and adsorption properties of hydroxyapatite surface-modified by cetylphosphate

セチル燐酸共存でヒドロキシアパタイトを合成した．その表面は疎水化されており有機化合物を容易に吸着するようになった．


Preparation and characterization of HAP particles having hydrophobic surface


Complex Formation between Na Ch-6-Sulfate and Acidic Aromatic Compounds on the Surface of Hydroxyapatite in an Aqueous Phase


Binding mechanism of Triton X and Triton N to the surface of hydroxyapatite in an aqueous phase


Intermolecular complex formationbetween methylorange and bovine serum albumin on the surface of hydroxyapatite in an aqueous phase

HAP表面でBSAとMOとが分子間複合体を形成する.この特異な構造について考察した.


Zeta potential of hydroxyapatite particles in the presence of polyethyleneglycol mono-p-isooctylphenylether and sodium dedecylsulfate in an aqueous phase

HAPにSDSとTx-100 が吸着したときのゼータ電位について考察した.

HAPにSDSとTx-100 が吸着したときのゼータ電位について考察した.


Adsorption mechanism of organic sulfonated compound,PonceauR, to hydroxyapatite in an aqueous phase --- Effect of sodium chloride on the adsorption amount

HAPへのPRの吸着量はNaClの影響を受ける.その機構を解析した.

HAPへのPRの吸着量はNaClの影響を受ける.その機構を解析した.


Formation and adsorption of intermolecular complex between alkyl phosphoric acid and nonionic surfactant on the surface of hydroxyapatite in an aqueous phase


Mechanism of the adsorption of organic sulfonated compounds by hydroxyapatite in an aqueous phase ----- Effects of number of sulfonate groups, lateral interaction and complex formation between the adsorbates on the surface


Change in secondary structure of silk fibroin during preparation of its microspheres by spray-drying and exposure to humid atmosphere

Journal of Colloid and Interface Science


Thermal gelation of aqueous curdlan suspension: Preparation of curdlan jelly

Curdlan jelly was prepared by heating an aqueous curdlan suspension at 70 degrees C for 5 min. Theophylline, as a model drug, was entrapped in the jelly network. Curdlan jelly had a hardness comparable with that of commercially available jelly for confectionary. Syneresis was observed for 8 days after the preparation and was not detected during the experimental term from the gel prepared from 10% w/v curdlan suspension. Release of theophylline from the jellies was sustained, and was increasingly delayed with an increase in the curdlan concentration. An aqueous curdlan suspension was studied by means of differential scanning calorimetry (DSC) up to 80 degrees C and down to -25 degrees C, and subsequent re-heating to 30 degrees C. Enthalpy increased with the concentration of curdlan, while the temperature at the onset of the endothermic peak decreased with the concentration of curdlan. The enthalpy due to thermal gelation of 1 mg curdlan was 12.2 mJ. An increase in curdlan concentration decreased the enthalpy and lowered the onset temperature of the endothermic peak during the DSC re-heating scan. The results are due to an increase in the amount of non-freezing water and freezing bound water and a decrease in free water. The number of water molecules entrapped in the curdlan jelly as non-freezing water was 8.1 per glucopyranose residue.

The Journal of Pharmacy and Pharmacology


Formation of intermolecular complex and polymer-drug interaction on the surface of hydroxyapatite in an aqueous phase


Cooperative adsorption of nonionic and anionic surfactants to the surface of hydroxyapatite in an aqueous phase


Improvement of encapsulation efficiency of water-in-oil-in-water emulsion with hypertonic inner aqueous phase

Water-in-oil-in-water (w/o/w) emulsions encapsulating tryptophan or theophylline were prepared where these compounds are regarded as model drugs. The effects of sodium chloride on the drug entrapment into the w/o/w emulsions and on the separation of aqueous phases were studied. The degree of encapsulation of tryptophan in the w/o/w emulsion increased with the concentration of sodium chloride added in the inner aqueous phase, while it decreased with that in the outer aqueous phase. As for theophylline, although the degree increased with a concentration of sodium chloride in the inner phase, the effect was smaller than that on tryptophan. The difference in the effects between on tryptophan and on theophylline was attributed to their partition coefficients. Theophylline was easily leaked out from the inner phase to the outer aqueous phase after its dissolution and diffusion in the oil phase due to a higher partition coefficient. More than 55% of the aqueous phase was separated from the w/o/w emulsion within 24 h, when sodium chloride was not added in the inner aqueous phase. However, the separation was not observed when more than 0.2M sodium chloride was added. To the contrary, sodium chloride added in the outer aqueous phase accelerated the separation. It was, therefore, concluded that sodium chloride in the inner aqueous phase plays an important role in suppression of the separation and in encapsulation of the drug which does not penetrate into the oil membrane.


Adsorption of nonionic surfactants, Triton X and Triton N, on hydroxyapatite after surface modification with sodium dodecyl sulfate in an aqueous phase

Studies in Surface Science and Catalysis


Interaction and complex formation of pluronic polymers with ionic surfactants


Adsorption characteristics of non-adsorbable nonionic surfactant, TX-100, on the surface of hydroxyapatite in the presence of an anionic surfactant


Drug Release from w/o/w emulsions prepared with different chitosan salts and concomitant creaming up

Water-in-oil-in-water (w/o/w) emulsions containing chitosan and tryptophan in the inner aqueous phase were prepared. The acids used to dissolve chitosan were formic, acetic, butyric and lactic acids. The effects of these organic acids and pH of the inner aqueous phase on the release of tryptophan and on the separation of the aqueous phase due mainly to creaming up during storage were studied. When the inner aqueous phase was an acidic chitosan solution, the release rate was almost the same irrespective of the acids mentioned above. When acetic and butyric acids were neutralized with sodium hydroxide, the release of tryptophan was prolonged. However, it was enhanced again by an excess amount of sodium hydroxide. On the other hand, the release was enhanced after neutralization of formic and lactic acids. Separation of the aqueous phase from the w/o/w emulsion during storage was remarkably delayed after neutralizing the chitosan solution containing acetic or butyric acids, while not so much in the cases of formic and lactic acids. It is concluded that these w/o/w emulsions were stabilized in the presence of neutralized chitosan gel suspensions containing acetate or butyrate ions in the inner aqueous phase.


Silk microspheres prepared by spray-drying of an aqueous system

Pharmacy and Pharmacology Communications


Development of a new type nozzle and spray-drier for industrial production of fine powders

Sophisticated nozzle and spray-drier were newly developed. The nozzle type was that of four-phase spraying, where two liquid streams and two air streams were blown off. The spray pattern from the nozzle was of a hollow-cone type. Mean diameter of droplets in the mist was 13.2 microm in weight average in the condition of blowing at 776 g/min in air flow and 500 ml/min in liquid flow. That is, the weight-based flow ratio of air to liquid was as small as 1. 55. The geometric standard deviation of the droplet size was less than 1.65. This nozzle was still available for a concentrated suspension up to 27% solid without formation of the sludge on the orifice. Thus, fine powder with 1.99 microm in mean diameter was obtained by means of the nozzle and the spray-drier newly developed by us. These are promising for industrial production of the fine powder with low energy and high recovery.

European Journal of Pharmaceutics and Biopharmaceutics


Effect of adsorption of dodecyl phosphate on the crystal growth and surface modification of hydroxyapatite in an aqueous phase


Binding of water-insoluble dye methyl yellow on the surface of hydroxyapatite in the presence of sodium dodecylsulfate in an aqueous phase


Comparison of lipiodol water-in-oil-in-water emulsion with oil-in-water emulsion : acute toxicity and deposition in liver after hepatic arterial administration in rats


Competitive and cooperative adsorption of bovine serum albumin and sodium chondroitin-6-sulfate on hydroxyapatite in an aqueous phase


Influence of the permeation enhancers 1-alkyl-2-pyrrolidones on permeant partitioning into the stratum corneum

In a previous study, the enhancing effects of a series of 1-alkyl-2-pyrrolidones (APs; 1-ethyl, 1-butyl, 1-hexyl, and 1-octyl-2-pyrrolidone) on the transport of steroidal permeants across hairless mouse skin were investigated via a parallel pathway skin model. Isoenhancement concentration conditions were deduced under which different APs induce essentially the same transport enhancement for the lipoidal pathway of the stratum corneum (s.c.). As a continuing effort to understand the mechanism of action of permeation enhancers, the influence of the APs on permeant partitioning into hairless mouse s.c. was investigated under the isoenhancement concentration conditions using beta-estradiol (E2 beta) as the model permeant. The amount of E2 beta uptake into s.c. was found to be essentially the same for all the APs under these isoenhancement conditions. This result suggests that inducing a higher partitioning tendency for E2 beta into the lipoidal pathway of hairless mouse s.c. is a principal mechanism of action of the APs in enhancing transdermal transport. The uptake of the APs into s.c. lipoidal domains was also determined, and the results show only a modest (approximately 2-fold) increase in the uptake of the APs in going from 1-ethyl-to 1-octyl-2-pyrrolidone under isoenhancement conditions. This indicates the potency of the APs as permeation enhancers is only very modestly dependent upon the alkyl chain length in this chain length region when compared at concentrations in the microenvironment where the action occurs in the lipid domains.


Zeta potential of hydroxyapatite in the presence of hydroxypropylcellulose and sodium dodecylsulfate in an aqueous phase (Effect of formation of the surface complex)


Depurination of Adenosine and deoxyadenosine monophosphates in the hemin- hydroperoxide system


Interaction of water-soluble porphyrin with DNA and RNA triplex


Interaction between hydroxypropylcellulose and surfactant and its effect on dispersion stability in an aqueous phase


Binding of meso-tetrakis(N-methylpyrridinium-4-yl)porphyrin to double helical RNA and DNA-RNA hybrids


Depurination of adenosine monophosphates in the iron porphyrin-cumene hydroperoxide system


ヒドロキシプロピルセルロースと硫酸ドデシルナトりウムとの界面複合体形成がO/W型大豆油エマルジョンの分散・凝集に及ぼす影響

Journal of the Pharmaceutical Society of Japan


無定形シリカの粒子表面細孔および1次粒子間間隙に浸入する水によって引き起こされるポリビニルピロリドン共存下でのコンドロイチン-6-硫酸ナトリウムおよびナトリウムカルボキシラトメチルセルロースの見かけの負吸着


Formation of intermolecular complex between polyvinylpyrrolidone and sodium dodecyl sulfate through hydrophobic interaction on the surfac e dodecyl sulfate through hydrophobic interaction on the surface of hydroxyapatite in an aqueous phase --- fllucculation of the HAP particles by the surface complex


Effect of imidazoles and pH on the peroxidase activity of the hemine-hydrogen peroxidase system


Formation of hydroxyapatite in the presence of bovine serum albumin in an aqueous phase


Effect of potasium polyvinylsulfate of various degree of sulfation on the formation of hydroxyapatite in an aqueous phase


Formation of a polymer complex between BSA and Na Chondroitin-6-sulfate in an aqueous phase and on a solid/water interface of kaolin


HAPの非化学量論的溶解に対する硫酸イオンと硫酸ドデシルイオンの影響

HAPの非化学量論的溶解に対する硫酸イオンと硫酸ドデシルイオンの影響


Hemin binding to DNA with bis-dentate acridine intercalation


Complex formation through hydrophobic interaction between PVP and SDS on the surface of HAP --- Modification to hydrophobic surface by adsorption of SDS


Increase in the amount of adsorption of NaChs on HAP owing to the volume effect of polymer coil of non-adsorbable polymer,PVP


単純塩の存在下におけるHAPの非化学量論的溶解

単純塩の存在下におけるHAPの非化学量論的溶解


高分子アニオンの占める領域からの低分子アニオンの排除 --- Chsアニオンと蓚酸アニオンの場合


NaChs 存在下におけるCaイオンと蓚酸イオンの蓚酸カルシウム1水和物に対する吸着と沈殿形成


蓚酸カルシウム1水和物に対するNaChs の吸着とそれにともなう蓚酸カルシウム1水和物の溶解


Complex formation of BSA with SDS on the surface of HAP


Effect of phsphorylated cellulose and BSA on the crystallization of HAP


Effect of sulfate group on the formation of HAP in an aqueous phase


水溶液中におけるモノアセトアセチンの加水分解反応に及ぼすpHと温度の影響

水溶液中におけるモノアセトアセチンの加水分解反応に及ぼすpHと温度の影響


Binding of mequitazine with PVP and NaAlg and its effect on the precipitation formation of mequitazine in an aqueous phase


Aggregation/dispersion of amorphous silica particles by simultaneous adsorption of two polymers in an aqueous phase


effect of phosphorylated organic compound on the adsorption of BSA by HAP


Interaction of alginic acid with organic diacidic base piperazine


Formation of HAP in the presence of phosphorylated PVA as a simplified model compounds for mineralization regulator phosphoproteins


Decrease in intrinsic viscosity of PVP in the presence of NaChs or NaCMC in an aqueous phase


Interaction of HAP with Na- and CaChondroitin-6-sulfate in an aqueous phase


Flocculation and formation of open structure of kaolinite suspension in the presence of PVP


The effect of PVP and SDS on the dispersity and fluidity of concentrated suspension of kaolinite