• Journal of Pharmaceutical Investigation
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• v.18 no.2
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• pp.43-47
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• 1988

In order to increase the dissolution characteristics of relatively water-insoluble metoclopramide (MCP), coprecipitates of MCP with polyvinylpyrrolidone (PVP), polyethylene glycol (PEG) 1000, 4000 or 6000 were prepared in various drug to polymer ratios. The dissolution rate of MCP-PVP coprecipitate was greater than those of MCP alone, MCP-PVP physical mixture and MCP-PEG coprecipitates. The dissolution rate of MCP-PEG 6000 coprecipitate was greater than those of MCP-PEG 1000 and MCP-PEG 4000 coprecipitates. The dissolution half-lives $(T_{50%})$ for MCP alone and 1:5 (w/w) MCP-PEG 6000 coprecipitate were determined by the log-probit method at $37^{\circ}C$ and found to be 4.17 and 0.98 min, respectively.

• Journal of Pharmaceutical Investigation
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• v.15 no.3
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• pp.100-112
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• 1985

Dissolution characteristics of flurbiprofen solvent deposited on ${\alpha}-cyclodextrin$, ${\beta}-cyclodextrin$, lactose and corn starch were studied to evaluate the pharmaceutical aspects of solvent deposition method where drug was solvent deposited on the surface of excipients. In a solvent deposition system, the drug to excipient ratio and kind of excipient affect much on dissolution rates of flurbiprofen. The solvent deposition system formation was confirmed by scanning electron microscope. By increasing the amounts of matrix, it was possible to enhance the dissolution rate of flurbiprofen solvent deposition system. The amount of flurbiprofen dissolved from ${\beta}-cyclodextrin$ deposition system (1:10) at 60 minutes was enhanced 6.5 times in water and 28 times in simulated gastric juice compared with flurbiprofen alone. Flurbiprofen solvent deposited system (1:10) enhanced dissolution rate greater than inclusion complex and dispersion system.

• Journal of Pharmaceutical Investigation
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• v.40 no.5
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• pp.277-283
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• 2010

CoQ with low melting temperature was exploited to improve its solubility by preparing its solid dispersions (SDs) with a meltable polymer, poloxamer 407 (P 407). P407 can be utilized for a relatively simple, quick, inexpensive, reproducible and potentially scalable manner in the low temperature melting method. CoQ 10 solubility and dissolution increased with increasing concentrations of P 407 in SDs. Comparison of the enhanced dissolution of CoQ 10 from different poloxamers suggested that the preparation of CoQ 10 SDs using P 407 as a meltable hydrophilic polymer carrier could be a promising approach to improve its dissolution.

• Journal of Mechanical Science and Technology
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• v.19 no.5
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• pp.1216-1225
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• 2005

$CO_{2}$ ocean sequestration is one of the promising options to reduce $CO_{2}$ concentration in the atmosphere because the ocean has vast capacity for $CO_{2}$ absorption. Therefore, in the present investigation, calculations for solubility and dissolution behavior of liquid $CO_{2}$ droplets released at 1000 m and 1500 m deep in the ocean from a moving ship and a fixed pipeline have been carried out in order to estimate the $CO_{2}$ dissolution characteristics in the ocean. The results show liquid $CO_{2}$ becomes bubble at around 500 m in depth, and the solubility of seawater is about $5{\%}$ less than of pure water. Also, it is shown that the injection of liquid from a moving ship is a more effective method for dissolution than from a fixed pipeline, and the presence of hydrate on liquid $CO_{2}$ acts as a resistant layer in dissolving liquid $CO_{2}$.

• Journal of Pharmaceutical Investigation
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• v.18 no.1
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• pp.23-30
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• 1988

The sustained-release micropellets containing rifampicin were prepared by spray congealing micropelleting technique using gelatin as the embedding matrix, and hardened by treating with the formalin-isopropanol mixture. Dissolution of rifampicin from micropellets was significantly retarded, and greatly dependent on formalin concentration, hardening time and pH of the dissolution medium. It was found that this prolongation was more distinguished in pH 1.2 dissolution medium rather than pH 7.4, which might be attributed to the swelling characteristics of gelatin used in the dissolution medium. In-vitro dissolution kinetics indicated that the drug release followed the first-order process.

• Journal of Pharmaceutical Investigation
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• v.15 no.4
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• pp.186-197
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• 1985

Polymorphs of piperacillin monohydrate were prepared by various sedimentation methods from piperacillin base for the purpose of developing piperacillin preparations for oral use. Solubility and dissolution rate of each form of the polymorphs were compared with each other. It was found that Form IV showed the highest solubility and the fastest dissolution rate among four forms of polymorphs. In general, the solubility and dissolution rate of two amorphous forms, Form IV and II were higher than those of two crystal forms, Form I and III. The apparent dissolution rates in the artificial gastric juice within 60 minutes were $0.65{\times}10^{-6}mole{\cdot}min^{-1}\;cm^{-2}$ for From IV, $0.36{\times}10^{-6}mole{\cdot}min^{-1}{\cdot}cm^{-2}$ for From II, $0.30{\times}10^{-6}mole{\cdot}min^{-1}{\cdot}cm^{-2}$ for From III and $0.18{\times}10^{-6}mole{\cdot}min^{-1}{\cdot}cm^{-2}$ for From I, respectively.

• Journal of Pharmaceutical Investigation
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• v.23 no.1
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• pp.55-59
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• 1993

Dissolution of mucosal adhesive tablets prepared with two polymers using hydroxypropylcellulose-H (HPC) and carbopol 934 (CP) was tested. Adhesive tablets containing HPC/CP and brilliant blue FCF (BB) were prepared from direct compression. Three factors of polymer ratio (HPC:CP), BB content and compression force were chosen as important factors of preparation and factorial analysis for these factors was carried out. Eight kinds of formulations from different combinations of three factors were prepared and dissolution test in pH 6.8 phosphate buffer solution was performed. Dissolution rate was significantly affected by HPC:CP ratio and BB content, but was not affected by compression force.

• Journal of Pharmaceutical Investigation
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• v.30 no.2
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• pp.85-91
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• 2000

We have studied the dissolution kinetics of two fast releasing tablets in four media, and the similarity of dissolution profiles was compared using 3 methods. Two of the methods were introduced from statistical algorithm of distance methods, which are maximum distance and Mahalanobis distance. The dissolution kinetics were also analysed using FDA method for similarity evaluation, and the results were compared with those obtained using the distance methods.

• Journal of the Korean Ceramic Society
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• v.56 no.6
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• pp.577-582
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• 2019

Recently, E-glass fiber is the one of most widely used ceramic fiber for aerospace fields. Recycling technology for waste of wind power blades is arising issue for reasons of low manageability and high cost of wastes. Though glass fiber is perfectly dissolved in hydrofluoric acid, low cost for recycling and harmless to human is important for recycling of blades. Chemically melted glass fiber will be used as different purpose like accelerator of hardening for shotcrete. In this study, dissolution process of glass fiber is tested in NaOH solution at low temperatures. In addition, difference in diameter reduction of glass fiber is observed by various alkali concentration and reaction times, treatment temperatures using FE-SEM.

• Journal of Pharmaceutical Investigation
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• v.41 no.6
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• pp.363-369
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• 2011

In this study, we demonstrated the release behavior of carvedilol with the content of polyvinylpyrrolidone K-30 (PVP K-30) and the effect of citric acid and fumaric acid as acidifiers on the release behavior of drug. In addition, it tries to inquire into the release behavior difference of the carvedilol according to the manufacturing method. The release behavior of the tablets was compared with Dilatrand$^{(R)}$ in the simulated gastric fluid (pH1.2). Differential scanning calorimeter (DSC), X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FT-IR) were characterized for the physicochemical properties of the tablets. In case of mixing the carvedilol and PVP K-30, in case the ratio of the carvedilol and PVP K-30 was 1:5, the release behavior was the highest among. As well as the dissolution rate of tablets manufactured by lyophilization and rotary evaporator was higher than physical mixture. The dissolution rate of containing acidifiers was more improved. But, rather the excessive amount of the acidifier addition reduced the dissolution rate.