• Archives of Pharmacal Research
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• 제7권1호
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• pp.33-40
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• 1984

In domethacin was microencapsulated with ethylcellulose using a modified spherical agglomeration process, aiming at a sustained release proparation without side effects on the stomach. The surface morphology of the microcapsules was examined using scanning electron microscopy. The microcapsules were porous and spherical, and their porosity increased with increasing the viscosity of ethylcellulose. In vitro dissolution process followed Higuchi's diffusion model for first 3 hr. Release rate of the drug from microcapsules decreased as the viscosity of ethylcellulose was decreased. The release rate also decreased with increasing the microcapsule size. The microcapsules induced less gastric ulcer in rats than raw drug.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.378-378
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• 2006

The preparation, characterization, and bio-testing of biocide incorporated silicone coatings for marine applications have been conducted. Derivatives of the biocide, Triclosan (5-chloro-2-(2, 4-dichlorophenoxy) phenol), were used to covalently attach the biocide moiety to a silicone backbone. The synthetic process allowed for control of the resulting coating's mechanical properties as well as antifouling/fouling release performance in laboratory and ocean site testing. The test results showed significantly reduce macro fouling with sustained fouling release characteristics for the coatings produced.

• Journal of Pharmaceutical Investigation
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• 제39권5호
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• pp.333-337
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• 2009

We aimed to optimize the formulation of porcine placental extract (PPE)-loaded liposomes for intramuscular administration and to investigate the effect of surface charges on the muscular retention in mice. PPE-loaded liposomes were formulated to have neutral, anionic, or cationic surface charges. The in vitro release profiles were studied by spectrofluorometry. In vivo distribution patterns at mice were studied using molecular imaging technology. Among the three types of liposomes, 1,2-dioleoyl-3-trimethylammonium-propane and 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-based cationic liposomes showed the most prolonged in vitro release profile. Consistent with the in vitro results, the in vivo distribution study revealed that the cationic liposomes were retained at the site of administration for the longest period. Our results suggest the potential of cationic PPE-loaded liposomes for sustained release of the components after intramuscular administration.

• 약학회지
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• 제47권2호
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• pp.78-84
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• 2003

Local anesthetics are used to reduce pain, but they are so frequently injected to patients. So, we prepared lidocaine solid lipid microspheres (SLM) as long acting abdominal injection using spray drying method and evaluated drug entrapment, particle size, SEM, zeta potential and in vitro and in vivo drug release pattern, The particle sizes of SLM were 30∼100$\mu$m and it is enough to inject into abdominal tissue. The entrapment efficiency of SLM was over 95％ as spray drying method. Surfactant and PC decreased the burst effect by 20∼30％. In in vivo test, C-6 showed controlled release concentration profile in plasma for 8 days and C-5 sustained longer than we expected.

• Nuclear Engineering and Technology
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• 제32권5호
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• pp.425-432
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• 2000

It has been an essential part for the safety assessment of nuclear power plants to understand various phenomena associated with the molten core-concrete interaction(MCCI) under severe accidents. In this study, the severe accident analysis code MELCOR was used to simulate the MCCI experiments such as SWISS and SURC test series which had been performed in Sandia National Laboratories(SNL). The calculation results were compared with corresponding experimental data such as melt temperature, concrete ablation distance, gas generation rate, and aerosol release rate. Good agreements were observed between MELCOR calculation and experimental data. The melt pool was sustained within the range of high temperature and the concrete ablation occurred continuously. The gas generation and aerosol release were under the influence of melt temperature and overlying water pool, respectively.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.424.2-424.2
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• 2002

The in vivo release characteristics of rhGH-loaded PLGA microsphere prepared using a double emulsion process from hydrophilic 50:50 poly(D.L-lactide-co-glycolide) (PLGA) polymers were analyzed. This formulation showed particle size of ca 53.1$\mu\textrm{m}$ with high drug incorporation efficiency. To investigate in vivo release kinetics without the interference of formation of antibodies to rhGH in the experimental animals, the animals were immunosuppressed by treatment with Cyclosporin. (omitted)

• 폴리머
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• 제28권1호
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• pp.59-66
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• 2004

온도에 의존하여 졸-젤 전이를 나타내는 온도민감성 리포솜을 함유하는 폴리 N-이소프로필아크릴아마이드 젤을 제조하였다. 온도민감성 리포솜의 표면은 3$0^{\circ}C$에서 하한임계용액온도를 나타내는 N-이소프로필아크릴아마이드와 옥타데실아크릴레이트의 공중합체를 이용하여 변형시켰다. 표면이 변형된 온도민감성 리포솜을 폴리 N-이소프로필아크릴아마이드 수용액에 혼합하였다. 혼합용액을 하한임계용액온도 이상으로 가열했을 때 물리적으로 가교결합이 이루어진 젤의 형태가 이루어지며, 이때 온도 민감성 리포솜이 함유된 폴리 N-이소프로필아크릴아마이드 젤이 만들어진다. 온도민감성 리포솜으로부터 약물의 방출은 형광강도를 측정하여 결정하였다. 폴리 N-이소프로필아크릴아마이드 젤 내부의 온도민감성 리포솜으로부터 약물의 방출은 온도가 증가할수록 지속적인 방출을 나타내었다.

• 한국응용과학기술학회지
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• 제33권3호
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• pp.428-434
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• 2016

본 연구에서는 알킬체인의 길이가 서로 다른 benzyltrialkylammonium chloride계 화합물을 합성하여 리포좀 제조에 응용하였다. 제조된 리포좀의 평균 입도분포, 제타전위, 방출거동 및 항균성을 조사하였으며, 사슬 길이에 따른 특성을 비교하였다. 리포좀의 평균 입도는 120~140 nm의 크기분포를 가졌으며 소수성 사슬의 길이가 증가할수록 큰 입자크기를 가졌다. 리포좀 용액의 제타전위는 양이온성 계면활성제인 benzyltrialkylammonium chloride를 첨가함에 따라 +80~90 mV의 값을 가지며 향상된 분산 안정성을 보였다. 방출거동에서는 사슬 길이에 따라 방출 속도를 조절할 수 있었으며 긴 사슬의 계면활성제를 첨가한 리포좀은 증가된 서방형 방출특성을 보였다. 또한, 리포좀의 포집효율은 25.9~27.5% 이었다.

• Carbon letters
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• 제10권3호
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• pp.208-212
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• 2009

Alginate-chitosan blend containing coconut-based activated carbon was prepared as a drug delivery carrier in order to improve the loading and releasing capacity of the drug. The activated carbon was incorporated as effective adsorbent for drug due to the extremely high surface area and pore volume, high adsorption capacity, micro porous structure and specific surface activity. Alginate-chitosan blend containing coconut-based activated carbon showed the sustained release for a longer period. Alginate-chitosan blend showed higher release of drug as the pH increased and higher release of drug as the content of chitosan decreased due to the pH-dependent solubility of blend components.

• Journal of Pharmaceutical Investigation
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• 제36권4호
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• pp.245-251
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• 2006

The novel microsphere blending and multiple emulsion method by single process was tried to prepare sustained release microspheres which release a physiologically active substance for long periods of time. A drug was separately dissolved in each of two or more oils containing biodegradable polymers to give the primary oil phases. The primary oil phases were dispersed in single aqueous phase in succession. From the drug-dispersed solution, the organic solvent was removed to produce microspheres. The accelerated drug release from the microsphere formulation prepared by single process through the multiple emulsion method was very similar to a physical blending of separately prepared microspheres using the same polymers. But long term release was not same. In this study, leuprorelin acetate loaded poly(lactide-co-glycolide) microsphere formulation for one-month delivery was developed by the multi-emulsion method followed by solvent extraction/evaporation method.