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A new calibration technique, referred to as e-trace, has been developed by the National Institute of Advanced Industrial Science and Technology (AIST). The e-trace technique enables rapid remote ca...

Emulsification of various common oils was investigated using natural β-cyclodextrin (β-CD) and its derivatives as emulsifiers. An oil/water (O/W) emulsion was formed using β-CD, whereas a water/oil (W/O) emulsion was formed using tripropanoyl-β-CD and tributanoyl-β-CD derivatives. Triacetyl-β-CD gave rise to both O/W and W/O emulsions. The type of emulsion was governed by the contact angle (θow), which the precipitate of CD origin make with the oil-water interface.

A sensitive micellar electrokinetic chromatographic method to analyze salbutamol, guaifenesin, and dyphylline employing 20 µm inner diameter capillaries was developed. Sensitive analysis of the drugs at a concentration range of about 0.5 to 60 µg/mL was demonstrated using large volume sample stacking with 75% acetonitrile as the sample diluent. Using dyphylline as the internal standard, detection limits were 0.07 µg/mL and 0.21 µg/mL for salbutamol and guaifenesin, respectively. Using the standard addition method, accurate determination of salbutamol and guaifenesin in syrup and capsule preparations was achieved. Recovery values were satisfactory (95 to 100%), but matrix interferences affected the reproducibility.

The effects of inorganic salts on micellization and solubilization of prednisolone in aqueous solution of poly(ethylene oxide)/poly(propylene oxide)/poly(ethylene oxide) triblock copolymer (Pluronic P85) were studied. The effect of inorganic salts on decrease in the cloud point and the critical micelle concentration (cmc) of Pluronic P85 was the order of Na2HPO4 > NaH2PO4 > NaCl > NaBr. Moreover, it was found that Pluronic P85 forms two kinds of micelles: monomolecular micelles and polymolecular micelles. The polymolecular micelle increased with increasing amount of added inorganic salts. Moreover, solubilization behavior is explained from the standpoint of salting out for prednisolone and association characteristics of Pluronic P85.

Separation of seven ginsenosides at elevated temperature by ultra high pressure liquid chromatography (UHPLC) on reversed phase C18‐ bonded silica stationary phase was studied. All separations were carried out with a binary mobile phase consisting of CH3CN/H2O in isocratic elution mode. It was found that increasing the column temperature resulted in efficient separation and complete resolution of seven ginsenosides. Generally, the separation efficiency increased as a function of temperature. The effect of the mobile phase velocity on the separation efficiency was also investigated.

The effects of counter‐anions on the reversed‐phase HPLC retention of zwitterionic quinolones were studied. Four counter‐anions, perchlorate, tetrafluoroborate, trifluoroacetate, and dihydrogenphosphate, were used as mobile phase additives. HPLC analysis was performed at a mobile phase pH 3, to ensure the complete protonation of the piperizine ring and to suppress the ionization of the carboxylic acid groups of the analytes. Results showed that retention factors of all analytes increased to varying degrees with increasing counter‐anion concentration. The increase in retention of the analytes is attributed to the chaotropic effect exhibited by the counter‐anions. Complete separation of all the studied compounds was achieved by varying the type and amount of counter‐anions present in the mobile phase. The changes in selectivity offered by these counter‐anions would be beneficial, especially for developing chromatographic methods for the analysis of quinolones in different sample matrices.

A novel cross‐linked chitosan phase was synthesized as a stationary phase in microcolumn liquid chromatography (micro‐LC). The cross‐linked chitosan phase was synthesized with a trifunctional cross‐linking reagent, 1,3,5‐triacryloyl‐1,3,5‐triazine (TAT), and the retention behavior for polycyclic aromatic hydrocarbons (PAHs) was compared with that obtained on several commercially available stationary phases including monomeric and polymeric octadecylsilicas (ODSs). The results demonstrated not only the applicability of the newly‐synthesized cross‐linked chitosan phases as the stationary phase, but also a strong molecular planarity recognition power of the cross‐linked chitosan phase over typical polymeric ODS phase. The excellent molecular planarity recognition ability of the chitosan phase can be explained by a rigid phase structure due to the three‐dimensional cross‐linking with TAT molecules.

The stability constants for the inclusion of butylbenzenes (BBs) with 2-hydroxypropyl-cyclodextrins (2HP-CDs) in aqueous solution have been determined using the static head-space method. The 1:1 stability constants were obtained by this method. For the complexation of BBs by 2HP-alpha-CD, the order of stability constants was n-BBisoBBtert-BB. In contrast, the order for complexation of BBs by 2HP-beta-CD was the opposite: tert-BBisoBBn-BB. The order of the stability constants by 2HP-gamma-CD was similar to that of 2HP-beta-CD, but the values of the stability constants were not significantly different in the BB types. In addition, the binding effects are discussed in relation to the different alkyl groups of BBs.

Novel cross-linked chitosan materials have been introduced as the stationary phase in microcolumn liquid chromatography (micro-LC). Three types of cross-linked chitosan phases were synthesized with changing the degree of cross-linking, and the retention behavior for polycyclic aromatic hydrocarbons (PAHs) was compared with that obtained by various commercially available stationary phases, including monomeric and polymeric octadecylsilicas (ODSs) and chemically modified chitosan phases. The results clearly showed the applicability of the newly-synthesized cross-linked chitosan phases as the stationary phase in LC. From the considerations of the shape selectivity, it was also demonstrated that the cross-linked chitosan phase, synthesized with a higher degree of cross-linking reaction, possessed a strong molecular planarity recognition power over typical polymeric ODS phase.

The mixing effects of 6-O-α-D-glucosyl-β-cyclodextrin (G-β-CD) and surfactants on the solubilization of (+)-α-pinene (αP, a fragrance) in aqueous solution were studied using a head-space gas chromatography technique. The findings show that the mixing of G-β-CD and surfactant result in negative synergistic effects on the solubility of αP.

A comparison of the solubilizing ability of cyclodextrins (CDs) and surfactants for (+)-α-pinene (αP, a fragrance) in aqueous solution was made using a static head-space gas chromatography technique. The findings show that the solubilizing ability of CDs for αP is competitive to that of surfactants.

The simultaneous determination of the stability constants for inclusion of alkanols with alpha-cyclodextrin (alpha-CD) was investigated in a mixed alkanol system using static head-space gas chromatography (SHSGC). The 1:1 stability constants obtained were in fair agreement with those obtained previously using other methods. The time required for determination of the stability constant was markedly reduced using this simultaneous SHSGC method.

The purpose of the present study was to investigate the effects of kallidinogenase on chorioretinal circulatory disorder, on the basis of chorioretinal blood flow and fundus findings, in a renal hypertensive rabbit model.In a renal hypertensive rabbit model produced according to Goldblatt's method, chorioretinal blood flow was continuously measured by noncontact laser Doppler flowmetry (LDF). Ophthalmography was conducted before and 30 minutes after drug administration.Measurement by LDF revealed 16% reduction in chorioretinal blood flow in the hypertension group compared with the control group. The administration of kallidinogenase dose-dependently increased chorioretinal blood flow in both groups, the hypertension group being more sensitive to kallidinogenase than the control group. In contrast, none of the controls (vinpocetine and DL-alpha-tocopherol nicotinate) exerted effects on chorioretinal blood flow in the hypertension group. Fundus examination demonstrated narrowing of the choroidal arterioles following an increase in blood pressure, and expansion of the arterioles following the administration of kallidinogenase.Kallidinogenase was shown to improve ophthalmic circulation by increasing chorioretinal blood flow in renal hypertensive rabbits.

The effects of inorganic salts on the solubilization of estriol was studied in an aqueous solution of a poly (ethylene oxide)/poly (propylene oxide)/poly (ethylene oxide) triblock copolymer (Pluronic L-64). The solubility of estriol increased with increasing Pluronic L-64 and salt concentrations. Furthermore, two clear transition points corresponding to the polymolecular micelle formation and a pronounced change in micellar structure of Pluronic L-64 were found on the solubility curves. The effectiveness of inorganic salts for increasing solubility of estriol followed approximately the lyotropic or Hofmeister series, except Li+.

Subfoveal choroidal neovascular membrane is a leading cause of legal blindness. Photocoagulation has been effective, but photocoagulation of the fovea causes a decrease in vision immediately after treatment. Surgical removal of the choroidal neovascular membrane is effective for choroidal neovascular membrane in some cases, but it restores useful vision for reading (20/40 or better) in a small number of cases of choroidal neovascular membrane not due to presumed ocular histoplasmosis syndrome. A new treatment for subfoveal choroidal neovascular membrane, foveal translocation, is an innovative procedure in which the fovea is translocated onto healthier retinal pigment epithelium. Three techniques have been developed to relocate the retina, 2 of which (retinotomy and scleral shortening) we performed in 5 cases each. Preliminary results in these 10 cases indicate that foveal translocation provides improvement of visual acuity in 40% of eyes and final visual acuities useful for reading (better than 20/40) in 20% of eyes undergoing translocation with either technique. Further study is essential to refine the amount of translocation needed and to decrease complications of the 2 techniques, including retinal detachment, proliferative vitreoretinopathy, macular pucker, corneal astigmatism, and constricted visual field.

Selective enrichment of rare earth elements and subsequent separation were performed by high-speed countercurrent chromatography (CCC) using a multilayer coiled column filled with a toluene solution of 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester as a stationary phase. A large volume of aqueous solution containing adjacent rare earth elements, holmium and erbium, was passed through the column, and then the rare earth elements enriched in the stationary phase were chromatographically eluted by the mobile phase of an appropriate pH value. Mutual separation with sufficient resolution was accomplished, and approximately linear relationship existed between the area of elution peak and the quantity of rare earth element injected.

Retention behaviors of various planar and non-planar polycyclic aromatic hydrocarbons (PAHs), and all carbon compounds so-called fullerenes with 2,4,6-(tri-tert-butylphenoxy)dimethyl (TBP) silica phase and benzyldimethyl (Benzyl) silica phase have been investigated using microcolumn liquid chromatography system. The results clearly indicate that these phases possess a “non-planarity” recognition capability of PAHs. Non-planar solutes were retained longer than planar ones with these phases under certain separation conditions, although the opposite trend where the planar solutes are retained longer than the non-planar ones was observed with typical octadecylsilica (ODS) phases. This unique behavior can be explained by the specific molecular-molecular interaction between non-planar solutes and the stationary phase moiety having a cavity like structure made by the three tert-butyls and phenyl ring of the moiety. The separation of C60 and C70 were also examined and the difference of the structural uni...

The volatility of synthetic fragrances (benzyl formate, benzyl acetate, benzyl propionate) from pluronic P-85 aqueous solution has been investigated by the dynamic headspace method The experimental results showed that the volatility of a more hydrophobic fragrance was strongly controlled by pluronic P-85. This volatile behavior was explained by the solubilization constants of fragrances between the micelle and bulk phase by semiequilibrium dialysis method.

The separation of yttrium and chemically-similar heavy lanthanoids has been studied by countercurrent chromatography (CCC) equipped with a multilayer coiled column containing a toluene solution of 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester as a stationary phase. The retention of the stationary phase in a coiled tubing was enhanced with increasing revolutional speed and with decreasing flow rate of the mobile phase. This high retention of the stationary phase improved the peak resolution. The mutual separation of rare earths with low separation factors was satisfactorily accomplished with good resolution through a single step of CCC.

Newly designed bonded phases have been synthesized and evaluated for the separation of fullerene molecules. Further investigations about the retention behaviour of fullerenes with these phases have been carried out systematically. In this study we describe the separation of fullerenes with novel bonded stationary phases in microcolumn high performance liquid chromatography (micro-HPLC) and also propose the basic separation mechanism of those molecules obtained from the preliminary chromatographic observations. The results indicate that the octadecyldiphenyl bonded silica phases, which have been synthesized from octadecyldiphenylchlorosilane as the silanization reagent, possess a better retentivity for fullerenes than the octadecyldimethylsilica phase (i.e. monomeric ODS phase) having a similar surface coverage value.

C60 and C70 fullerenes were chromatographically separated with triphenyl, diphenyl and monophenyl bonded silica phases in microcolumn liquid chromatography. The results indicate that the triphenyl bonded phase having the narrowest pore size possesses the best separation performance among the evaluated phases. The retention power of the triphenyl bonded phase for C60 and C70 was much greater than that of typical octadecylsilica (ODS) phases, although the separation factor between C60 and C70 was almost comparable to that of ODS phases. With the triphenyl bonded phase, a smaller temperature dependence than ODS phases was observed for the separation of C60 and C70.

In situ hybridization was used to detect intracellular Staphylococcus aureus and S. epidermidis in mouse phagocytic cells after experimental infection of C3H mice with Staphylococci via abdominal or intravenous injection. Isolated ascites or whole blood were tested by the phagocyte smear technique, using bacteriolytic enzymes to preserve phagocytic cell morphology. The exposed bacterial DNA was visualized as intracellular hybridized signals by use of biotinylated DNA probes and by immunocytochemistry using streptavidin-alkaline phosphatase conjugates as detector molecules. These DNA probes, prepared from randomly cloned genomic DNA fragments of S. aureus and S. epidermidis, were strain-specific and did not cross-hybridize either in situ or on dot-blot hybridization. This technique of in situ hybridization with phagocyte smears is useful for detection and diagnosis of intracellular bacteria regardless of viability.