• Fisheries and Aquatic Sciences
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• 제1권1호
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• pp.30-34
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• 1998

Rotifer culture fed on five types of artificial microparticle diets were evaluated to substitute the natural diets such as Chlorella or w-yeast. These microparticle diets including solidified blood using squid oil (SBSO), solidified blood using soybean oil (SBSB), nylon protein walled particle (NPW) simple coacervation oil capsule (SCO), complex coacervation oil capsule(CCO), were tested for the evaluation of feeding efficiency. The prepared micro particle diets had diameters ranging from 3 to 30 Jim. Rotifer culturing experiments were carried out in 3-liter beakers for 13-16 days. The initial inoculum density of rotifers was 10 ind./ml. The rotifers fed on Chlorella or $\omega-yeast$ showed maximal densities of 2,000 ind./ml in 9 days or 500 ind./ml in 7 days, respectively. Those fed on SBSO, SBSB or NPW showed maximal densities of 1568 ind./ml, 586 ind./ml or 503 ind./ml, respectively and the reproductive rates for those diets were equivalent to or better than w-yeast. However, the coacervated oil capsule showed lower maximal densities of 400 ind./ml for SCO and less than 100 ind./ml for CCO due to the unbalanced diet formulation and indigestibility.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
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• pp.321-323
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• 2005

We report a microcapsule-based electronic ink display technique, containing hollow titania particles which were prepared via a complex coacervation method using gelatin and gum arabic. In order to reduce density mismatch between nanoparticels and dielectric medium, hollow titania particles were introduced. Microcapsules were then prepared using gelatin to improve the elasticity of the microcapsule wall and their electrophoretic characteristics were $investigated^1$

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2001년도 가을 학술발표회 논문집
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• pp.397-400
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• 2001

상변화물질(phase change material, PCM)은 외부온도변화에 따른 상변화에 따라 흡열과 방열성을 반복적으로 나타내는 물질로서 건축, 우주항공분야 등에서 열전달매체나 열조절시스템에 응용되어 왔다. 이러한 PCM의 응용방법은 PCM을 미세한 입자(직경이 약 100$\mu\textrm{m}$)로 만들어 직접 운반유체 속에 분산시켜 이용하거나, PCM을 심물질로 하는 마이크로캡슐을 제조하여 이용하는 방법을 들 수 있다. (중략)

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.249.1-249.1
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• 2003

The objective of the study was to develop an oral delivery system to increase the stability and efficacy of iron casein succinylate. Aqueous nanoparticles were prepared using complex coacervation of the oppositely charged chitosan and iron casein succinylate with polyethyleneglycol (PEG). The physicochemical properties of nanoparticles were investigated using dynamic light scattering, zeta potential and scanning electron microscopy. Chitosan-iron casein succinylate interactions were investigated in solid state by differential scanning calorimetry (DSC) and FT-IR spectrometry. (omitted)

• Archives of Pharmacal Research
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• 제16권1호
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• pp.50-56
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• 1993

The microencapsulation of sodium naproxen with Eudragit. RS was studied by coacrtvation/phase separation process using Span 80 in mineral oil/acetone system. Various factors which affect the mciroencapsulation, e.g., stirring speed, and surfactant concentraction, Eudagit RS concentration and loading drug amounts were examined. For the evaluation of the prepared microcapsules, release rate, particle size distribution and surface appearance as well as in vivo test were carried out. The addition of n-hexane and freezing of microcapsules accelerated the hardening of microcapsules. The optimum concentration of Span 80 ti prepare the smallest microcapsules was the same value with the CMC of Span 80 in solvent system. When 1.5% (w/w) Span 80 was used, the smallest microcapsules were formed $(30.02\pm5.05\mu$ in diameter) belonging to the powder category showing smooth, round and uniform surface. The release of sodium naproxen was retarded by microencapsulation with Eudragit RS. The Eudragit RS microcapsules showed significantly increased AUC and MRT and deceased Cl/F in rabbits.

• Biotechnology and Bioprocess Engineering:BBE
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• 제6권4호
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• pp.212-230
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• 2001

Recent advances in recombinant DNA technology have resulted in development of many new protein drugs. Due to the unique properties of protein druges, they have to be delivered by parenteral injection Although delivery of protein drugs by other routes, such as pulmonary and nasal routes, has shown some promises, to date most protein drugs are administered by par-enteral routs. For long-term delivery of protein drugs by parenteral administration, they have been formulated into biodegradable microspheres. A number of microencapsulation methods have been developed, and the currently used microencapsulation methods are reviewed here, The microen-capsulation methods have been divided based on the method used. They are: solvent evapora-tion/extraction; phase separation (coacervation);spray drying; ionotropic gelation/polyelectrolyte complexation; interfacial polyumerization and supercritical fluid precipitation. Each method is de-scribed fro its applications, advantages, and limitations.

• Journal of Pharmaceutical Investigation
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• 제12권4호
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• pp.112-125
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• 1982

Sulfamethoxazole particles were microencapsulated using the gelatin-acacia complex coacervation method. Micromeritic properties and dissolution characteristics of the microcapsules were studied. The particle size distribution followed log-normal form. As the hardening time increased, the particle size and wall thickness increased ($45.3-52.0\;{\mu}m$, $2.02-5.12\;{\mu}m$, respectively). This is considered to be due to the cross-linked wall structure of formalized microcapsules which prevents shrinking of gelatin during the dehydration and drying processes. An increase of hardening time clearly delayed the release rate. The in vitro 50% dissolution time $(t_{50})$ for unencapsulated sulfamethoxazole powder was less than 3 min.; for microcapsules hardened for 30 min, the $t_{50}$ was 20.1 min.; for those hardened for 60 min. the $t_{50}$ was 25.0 min.; for those hardened for 120 min., the $t_{50}$ was 35.8 min. The surface of the unhardened microcapsules was smooth and had no cracking or pore penetration. However, the surface of the hardened microcapsules was folded and invaginated.

• Journal of Pharmaceutical Investigation
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• 제19권1호
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• pp.29-37
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• 1989

For the prevention of the aggregation during microencapsulation, the effects and role of polyisobutylene(PIB), as a protective colloid, were studied. The effects of sealant treatment on the microencapsulation were studied. Methyldopa was microencapsulated with ethylcellulose (EC) by polymer deposition from cyclohexane by temperature change using PIB. The EC-microencapsulated methyldopa was sealed with spermaceti. The dissolution of methyldopa was influenced by the drug to wall ratio. When PIB was used, low aggregation of microcapsules occurred and the surface was smooth with a few pores. Treatment of microcapsules with spermaceti retarded the release of methyldopa, the release being affected by the percentage of sealant used and the particle size of the product.

• 한국의류학회지
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• 제20권3호
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• pp.512-518
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• 1996

Microcapsules containing 2, 4, 4'-trichloro-2-hydroxydiphenyl ether and perfumes were prepared by the coacervation using poly (vinyl alcohol) and crosslinking agents. Effects of dispersing agents, core materials, agitating speed and crosslinking agents on microcapsule size were investigated. The mean and deviation of microcapsule diameters decreased with increasing agitation speed. The diameters of m;crocapsules decreased with increasing dispering agent concentration at 6, 000 rpm of agitation speed, but it was not changed at 10, 000 rpm. The dispering effect of PVA is better than that of gum arabic. The slight increase in the diameter of microcapsule was observed when the amount of core material was increased. As the amount of crosslinking agent was increased, the diameter of microcapsule was decreased.

• 대한의용생체공학회:의공학회지
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• 제10권1호
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• pp.59-66
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• 1989

The Applicability of chitin or chitosan microsphere as means to achieve sustained release of p-aminosalicylic acid(PAS) has been examined. The microsphere of chitin or chitosan containing PAS were prepared by coacervation in acidic aqueous system in range of pH 2.0-4.0. The dissolution test of PAS from polymeric drug system was carried out in vitro test. The dissolution rate of PAS from the microsphere with chitin was significanthly lower than that from the microsphere with chitosan.The dissolution rate of PAS from the microsphere was decreased with increasing of concentration of chitin and chitosan. The sustained release of PAS from the microsphere was more effective at pH 1.2 than pH 6.8.