• Journal of Pharmaceutical Investigation
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• 제21권4호
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• pp.253-262
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• 1991

Microencapsulation of sodium ascorbate with cellulose acetate phthalate(CAP) by coacervation/ phase separation method were carried out. Various factors affecting microencapsulation, i.e., surfactant concentration. CAP concentration, stirring speed and treatment of spermaceti as a sealing agent were studied. Dissolution rate. particle size distribution, surface feature and stability test were investigated. CAP microcapsules prepared using 0.5% span 80 as a surfactant showed smooth and round surfaces. The release of sodium ascorbate was retarded by microencapsulation with CAP and by sealant treatment with spermaceti. When triturated with sodium bicarbonate, CAP microcapsules were more stable than unencapsulated sodium ascorbate under various RH conditions at $37^{\circ}C$.

• 약학회지
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• 제33권5호
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• pp.312-318
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• 1989

Microcapsule of Propranolol HCl with Cellulose Acetate Phthalate (CAP) by coacervation-phase separation method was studied. Encapsulation was carried out in the CAP-liquid paraffin-acetone ethanol solvent system. The optimum weight ratio for microencapsulation in the CAP-liquid paraffin-solvent system was 1.32:89.18:9.50 or 1.65:89.42:8.93. The wall thickness of microcapsules increased according to increasing of CAP concentration, but dissolution rate decreased. The dissolution of propranolol-HCl in simulated gastric and intestinal fluid test solution was completed within 3 min., but T50% of propranolol HCl from 10.0% CAP-microcapsules were 390 min. and 210 min. respectively. The released amount from 12.5% CAP-microcapsules was 41.8% within 720 min. in simulatd gastric fluid test solution and T50% of those in simulated intestinal fluid test solution was 250 min.

• 한국의류학회지
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• 제20권5호
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• pp.870-876
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• 1996

Microcapsules containing 2,4,4'-trichloro-2-hydroxydiphenyl ether (DP) and perfumes were prepared by the coacervation using poly (vinyl alcohol) and crosslinking agents. Internal phase content, percent releasing of core materials, antimicrobial activities of microcapsules and fabrics treated with them were investigated. The internal content of microcapsules containing perfumes and DP are increased with increasing perfumes. The internal content of cacharia in the microcapsue was higher than that of lemon and its maimum value was 93%. The microcapsules containing perfumes and DP did not release cacharia and lemon at roonl temperature. But the amount of perfumes released from microcapsules were increased with temperature and time of microcapsules containing DP and perfumes showed 100% reduction percentage of bacteria. The size of obstruction of fabrics treated with microcapsule containing DP and perfumes were increased with DP content in microcapsules.

• 청정기술
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• 제27권1호
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• pp.55-60
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• 2021

항생제는 감염병 환자의 치료, 농수축산업의 생산성 향상을 위한 목적으로 광범위하게 사용되는 약물이다. 그러나 항생제 과용 및 낮은 생분해성으로 인해 상당량이 하수로 누출되어 환경오염을 유발하며 내성 박테리아 출현을 촉진하고 있다. 본 연구에서는 생분해성 혈청 단백질인 알부민을 항생제 흡착제로 사용하기 위한 가능성을 탐구하였다. 혈청 알부민은 다양한 대사 산물과 호르몬을 모든 조직의 혈관 외 공간으로 운반하는 천연 혈액 단백질이다. 혈청 알부민은 수용성이 높지만 이온성, 친수성 또는 소수성 분자를 쉽게 수용하는 고유 결합 부위를 가지고 있어 나노 흡착제로 유망한 물질이다. 코아세르베이션(coacervation)을 유도하기 위해 탈용매제인 에탄올을 알부민 수용액에 적가하여 150 ~ 170 nm 크기 범위의 알부민 나노 입자로 탈수화 및 액-액분리 하였다. 글루타르알데히드 가교제를 첨가할 경우 알부민 나노입자의 크기 안정성 및 동질성이 증가하였다. 항생제 아목시실린에 대한 알부민 나노입자의 흡착능 평가에서 가교제 사용 농도, pH에 따른 흡착능의 차이가 관찰되었다. 분광광도법으로 측정한 알부민 나노입자의 단위질량당(mg) 최대 흡착능은 pH 4.0 수용액에서 아목시실린 12.4 마이크로그램(㎍)이다. 이러한 결과는 물에서 항생제를 제거하는 천연 나노 흡착제를 제조하기 위한 구성 물질로서 혈청 알부민의 잠재력을 보여준다.

• Bulletin of the Korean Chemical Society
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• 제32권4호
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• pp.1277-1281
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• 2011

Making use of chitosan (CS) and ethylenediaminetetraacetic acid (EDTA) as a reaction system, CS-EDTA nanoparticles were synthesized through a facile counterion complex coacervation method. $Ag^+$ could enter porous CS nanoparticles synthesized with this method, allowing Ag nanoparticles within chitosan nanoparticles were synthesized by reducing silver nitrate with chitosan. Because of the noncovalent interaction between CS and EDTA, the EDTA could be easily removed via dialysis against water, and pure core/shell-type Ag/CS nanoparticles could be obtained. The nanoparticles showed higher antibacterial activity toward E. coli than the active precursor Ag nanoparticles and CS.

• 대한화장품학회지
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• 제20권1호
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• pp.37-51
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• 1994

Glutaraldehyde를 사용하여 화학적인 가교반응에 의해 empty cross-linked chitosan microcapsule을 제조하였다. 또한 chitosan bead는 sodium hydroxide 용액을 이용한 coaervation에 의해 제조하였다. 이들의 제조를 위해 수상/유화제/유기상으로 이루어진 w/o emulsion을 형성시킨 후 에멀젼의 안정성에 영향을 미치는 요소들에 대해 조사하였다. 보조계면활선제로 n-hexanol을 첨가한 결과 유화안정성이 상승적으로 증가하는 경향을 보였다. Chitosan microcapsule은 광택이 나는 형태로 내부가 투명한 반면 chitosan bead는 백탁으로 내부가 불투명하며 매우 porous한 구조를 하고 있었다. Chitosan bead의 유리 아미노기의 분석은 picric acid titration으로 수행하였으며, 아미노산 반응의 종결여부는 ninhydrin color test에 의해 판정하였다. 또한 fluoroscamine에 의한 형광분석으로 chitosan bead의 표면에 많은 반응성 아미노기가 존재하고 있음을 정성적으로 확인할 수 있었으며, 이를 생리활성 펩티드의 커플링 반응에 이용할 수 있었다. 모델 펩티드로서 콜라겐의 receptor 부분에 해당하는 생체내 growth factor로 알려진 Gly-His-Lys를 각 아미노산 유도체를 차례로 커플링하여 chitosan bead 위에서 합성할 수 있으며, 세포 성장인자와 같은 여러 가지 생리 활성 펩티드의 운반체로서 chitosan bead가 쉽게 이용될 수 있는 가능성을 보여 주었다.

• 한국축산식품학회지
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• 제37권6호
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• pp.833-839
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• 2017

In this study, the physicochemical and sensory properties of Gouda cheese supplemented with microcapsules of chili pepper extract were evaluated. Microcapsules of pepper extract were prepared by coacervation technique using gum acacia-gelatin wall and chili pepper oil core. Changes in pH, lactic acid bacteria (LAB) population, and free amino acid (FAA) content after supplementation of Gouda cheese with chili pepper capsules were monitored during ripening. Texture and sensory characteristics of the Gouda cheese ripened for 6 months were evaluated. The supplementation of pepper extract microcapsules (0.5% or 1%, w/w) did not influence the pH values and LAB content of the Gouda cheese (p<0.05) during the ripening period. While the content of total FAA increased with the ripening process in all the cheese groups (p<0.05), no significant difference (p<0.05) in the content of total FAA was observed among the sample groups at each time point. The addition of pepper extract microcapsules (1%, w/w) to Gouda cheese significantly decreased hardness (p<0.05) and negatively affected sensory attributes in terms of taste and texture (p<0.05). The results demonstrated that supplementation with 0.5% pepper extract microcapsules could provide additional bioactive ingredients, along with maintenance of the quality of Gouda cheese.

• 약학회지
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• 제32권1호
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• pp.26-39
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• 1988

Eudragit $RS^{\circledR}$ polymer was used as a wall material for the microencapsulation of aspirin by a phase separation method from chloroform-cyclohexane system with 5% polyisobutylene (PIB) in cyclohexane, and microcapsules obtained were evaluated by particle size analysis, scanning electron microscopy (SEM), drug release and drug stability test. With PIB as a coacervation inducing agent, smooth and tight microcapsules with less aggregation were obtained. Below 1 : 0.3 core-wall ratio, it was possible to coat individual particle. Variation of production conditions showed that increasing the proportion of wall material, particle size and wall thickness of microcapsules and the concentration of paraffin wax in cyclohexane as a sealant sustained drug release rates effectively. SEM confirmed that larger microcapsules after drug release did not rupture into smaller particles but contained a few small pores on the surface. Aspirin release from Eudragit $RS^{\circledR}$ coated microcapsules was independent of the pH of medium, and the mechanism of drug release from non-sealed and sealed microcapsules appeared to fit Higuchi matrix model kinetics. Aspirin in the mixture of aspirin microcapsules and sodium bicarbonate was by far more stable than that in the mixture of pure aspirin and sodium bicarbonate.

• Journal of Pharmaceutical Investigation
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• 제26권4호
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• pp.273-280
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• 1996

Chondroitin sulfate/gelatin microspheres containing dexamethasone 21-acetate were prepared by complex coacervation method and their release patterns were examined in vitro. Microspheres prepared with a small amount of crosslinking agent had smooth surface and few pores, but those with a large amount of crosslinking agent were more porous and less spherical. In vitro release patterns were varied by changing polymer/drug weight ratio and amount of crosslinking agent. The release rate of dexamethasone 21-acetate in the presence of collagenase was faster than that in the absence of collagenase. Anti-inflammatory effect of dexamethasone 21-acetate microspheres was more efficient than that of dexamethasone 21-acetate solution in carrageenan-induced arthritis in the rat. On the basis of the above results, we might expect the degradation and drug release rate of these microspheres to be regulated by the degree of crosslinking and the level of enzymes. In patients with severe rheumatoid arthritis who have high concentration of collagenase, more drug would be released from the microspheres. An intra-articular injection therapy of rheumatoid arthritis with desired release kinetics could be developed to enhance patient compliance and therapeutic index.

• 한국토양환경학회지
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• 제4권3호
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• pp.17-24
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• 1999

토양오염 디이젤 제거에 대한 토양 세척기술의 적용을 위해 디이젤 제거효과가 좋은 비이온 계면활성제를 선택하기 위한 조건 중 소수성 사슬구조의 영향을 고찰하였다. 비이온 계면활성제는 CMC값이 낮고, 생분해성이 좋으며, 유기 오염물질에 대한 용해 능력이 커서 디이젤과 같은 NAPL류 제거에 효과적으로 사용될 수 있다. 비이온계 계면활성제 구조 내 소수성 탄화수소 사슬의 길이와 불포화결합의 존재는 흡착과 디이젤 제거에 영향을 미치며, 비이온계 계면활성제의 kaolin토양흡착과 디이젤 제거는 서로 밀접한 관계를 가지고 있다. 친수성기의 구조가 서로 동일한 계면활성제 중에서 소수성 탄화수소 사슬길이가 12개로 비교적 짧고 HLB값이 클 때 상대적으로 낮은 흡착평형농도와 높은 디이젤 제거효율을 나타냈다. 소수성 사슬 내에 불포화 탄화수소가 존재할 때 낮은 흡착평형농도와 높은 디이젤 제거 효율을 나타냈다. 농도에 따른 제거경향은 흡착이 평형에 도달한 후에 최대의 제거 효율을 나타냈으며 그 이상의 농도에서는 오히려 제거효율이 감소하는 현상이 나타났다.