• Journal of Pharmaceutical Investigation
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• 제15권2호
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• pp.45-52
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• 1985

For the model tablets using mannitol and Avicel PH 101 as excipients, the patterns of disintegration and dissolution from the differences of physical properties were investigated. It was found that the patterns in the dissolution and binding forces in the interaction of materials by estimates of solid-solid or liquid surface free energy due to cohesive or adhesive properties of materials, and solid surface free energy in binding forces of tablet should be considered as an important factor in dissolution processes.

• Journal of Pharmaceutical Investigation
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• 제13권3호
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• pp.100-103
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• 1983

Coprecipitates of sulpiride and polyethylene glycol (PEG) decrease the dissolution rate of sulpiride and the degree of decrease is reversely proportional to molecular size of PEG and proportional to increase of PEG ratios in coprecipitates. The physical mixtures of sulpiride and PEG increase the dissolution rate of sulpiride.

• Journal of Pharmaceutical Investigation
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• 제20권2호
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• pp.65-71
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• 1990

Some studies reported physicochemical factors of drugs affecting solubility and dissolution rate. However, few have been reported about pharmaceutical application of crystal forms (habits). Therefore, using acetylsalicylic acid and phenacetin as model substances, we monitored the effects of crystal forms on the dissolution rates.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1998년도 춘계학술발표회논문집(2)
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• pp.154-159
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• 1998

In order to assess the susceptibility of the environmentally assisted cracking(EAC) on SA508 Cl.3 steel in primary water condition, potential step test and slow strain rate test(SSRT) were conducted in a simulated crack tip condition. In this test, anodic dissolution was dominant in the crack tip environments. Proposed simple dissolution model is a modification of Hishida's anodic dissolution model at the plastic zone. One can predict actual crack growth rate with the smooth specimen through this model.

• Journal of Pharmaceutical Investigation
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• 제22권4호
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• pp.307-315
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• 1992

Dissolution rate of practically insoluble mefenamic acid was improved by roll mixing with sodium lauryl sulfate (SLS) or polyvinylpyrrolidone (PVP). The dissolution rate of the drug roll mixtures with SLS was superior to that of roll mixtures with PVP. The maximal dissolution rate was found in the roll mixtures system with SLS content of 60%. The dissolution rate of mefenamic acid roll mixtures with SLS content of 60% reached to the maximum value after 10 min of roll mixing. The transport of roll mixtures with SLS across rat jejunum was studied by the perfusion method using everted rat jejunum in vitro. The absorption rate of roll mixtures was superior to that of mefanamic acid.

• Journal of Mechanical Science and Technology
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• 제14권11호
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• pp.1276-1285
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• 2000

The solubility, the surface concentration and the dissolution behavior of carbon dioxide in deep sea were numerically investigated. Base on the calculations the relations between the surface concentration of liquid carbon dioxide droplet with the hydrate film and the solubility and those between the ambient carbon dioxide concentration in the plume and the dissolution rate were obtained. The result show that a carbon dioxide droplet is released both at 1000 m in depth with the initial droplet diameter of 0.011 m or less and at 1500 m in depth with a diameter of 0.015 m or less, and the droplet is completely dissolved below 500 m in depth. The hydrate film acts as a resistant layer for the dissolution of liquid carbon dioxide, and the effect of the hydrate film on the dissolution of liquid carbon dioxide depended upon the depth.

• Journal of Pharmaceutical Investigation
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• 제14권3호
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• pp.122-130
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• 1984

The dissolution profiles of the seven branded prednisolone tablets were determined by means of available compendium. Those tablets were stored at $40^{\circ}C,\;50^{\circ}C\;and\;60^{\circ}C$ for 15, 30 and 60 days respectively. Under the stress conditions, the dissolution efficiency showed significant changes. It is considered that the determination of shelf life of drug from these aging effects is possible because the dissolution data followed a logarithmic distribution. There were no substantial differences of dissolution between two prednisolone formulations with different particle size not larger than $100\;{\mu}m$. The effect of two starches (corn and potato) on the rate of dissolution of prednisolone from dosage form was also investigated. All marketed tablets met the requirement of the established compendium.

• Journal of Pharmaceutical Investigation
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• 제13권3호
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• pp.104-109
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• 1983

The effect of diluents on the dissolution rate of indomethacin was studied and the dissolution rate for the marketed products was compared to establish the quality standard for indomethacin preparation. The results are as fellows 1. The effect of test methods was not significant in the case of paddle method but was greatly effected in the case of basket method. 2. The effect of diluents was not significant generally, but in the case of starch dissolution rate was greatly effected. 3. The dissolution rate was remarkably decreased in proprotion to increase of capsule size. 4. The marketed products met the KP dissolution requirement but showed a little difference due to manufacturers.

• Journal of Pharmaceutical Investigation
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• 제28권2호
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• pp.81-85
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• 1998

Three polymorphic modifications and two pseudopolymorphic modifications of cefotaxime sodium were obtained by crystallization from different organic solvents. The isolated crystal forms were characterized by UV spectrophotometry, DSC, TGA and X-ray crystallography. Crystal forms of cefotaxime sodium were also compared by dissolution rate. The dissolution rate of form 1 was the highest, followed by form 2, form 4, form 6, form 5 and form 3. Among these polymorphic modifications the dissolution rate of form 3 and form 5 was much slower than that of cefotaxime sodium on the market. All forms showed no change after 2-month storage test in the silica gel desiccator. But after the storage of 2-month at 95% relative humidity condition, all forms were deliquesced by hygroscopic property except form 1 that showed the highest dissolution rate. At 52% relative humidity condition, form 1, form 2 and form 6 had no evidence of phase transformation, but form 3, form 4 and form 5 were also deliquesced.

• Journal of Pharmaceutical Investigation
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• 제20권3호
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• pp.121-127
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• 1990

Mefenamic acid has been widely used clinically as an anti-inflammatory analgesic. It has poor solubility in water $(41\;{\mu}g/ml)$ and there is the difficulty of dissolution in the mefenamic acid capsules. A study was made to investigate the effect of various surfactants on the dissolution of mefenamic acid capsules. The surfactants used were sodium lauryl sulfate (SLS), Pluronic F-68, F-77, and F-127. Mefenamic acid capsule containing surfactant showed significantly improved dissolution characteristics. The dissolution rate was fast in the order of SLS > F-77 > F-68 > F-127 in mefenamic acid capsules containing 0.2 w/w % surfactant. SLS was selected for further study on the bioavailability in rabbits. The area under the plasma concentration-time curve $(AUC_{0-24})$ of mefenamic acid capsule containing SLS was higher than one of mefenamic acid capsule not containing surfactant.