• Biotechnology and Bioprocess Engineering:BBE
• /
• v.9 no.3
• /
• pp.179-183
• /
• 2004

A biocompatible polyelectrolyte complex multilayer (PECML) film consisting of poly-L-lysine (PLL) as a polycation and hyaluronic acid (HA) as a polyanion was developed to test its use for surface modification to prevent cell attachment and protein drug delivery. The formation of PECML through the electrostatic interaction of HA and PLL was confirmed by contact angle measurement, ESCA analysis, and HA content analysis. HA content increased rapidly up to 8 cycles for HA/PLL deposition and then slightly increased with an increasing number of deposition cycle. In vitro release of PLL in the PECML continued up to 4 days and ca. 25% of HA remained on the chitosan-coated cover glass after in vitro release test for 7 days. From the results, PECML of HA and PLL appeared to be stable for about 4 days. The surface modification of the chitosan-coated cover glass with PECML resulted in drastically reduced peripheral blood mononuclear cell (PBMC) attachment. Concerned with its use for protein drug delivery, we confirmed that bovine serum albumin (BSA) as a model protein could be incorporated into the PECML and its release might be triggered by the degradation of HA with hyaluronidase.

• Bulletin of the Korean Chemical Society
• /
• v.34 no.5
• /
• pp.1333-1338
• /
• 2013

Chitosan-based nanoparticles (CSNP) were prepared through ionic cross-linking and gelation of chitosan (CS) by tripolyphosphate (TPP). CS properties such as molecular weight, and preparation conditions were screened and the resulting nanoparticles were examined by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The obtained particles were consistently spherical with an overall diameter of approximately $107{\pm}20$ nm. They were successfully used as a carrier for Zidovudine, an anti-human immunodeficiency virus (HIV) which, to our knowledge, is novel. The encapsulation ability, loading capacity, and controlled release behavior for these CSNP was evaluated. Results indicated that their intrinsic properties were strongly affected by properties inherent to CS such as molecular weight, and by the preparation condition, such as cross-linking density, which depends on the concentration of the cross-linker. In vitro release tests for the entrapped zidovudine showed that the CNNP provided a continuous release that can last upwards 20 h.

• Archives of Pharmacal Research
• /
• v.10 no.1
• /
• pp.42-49
• /
• 1987

This study is to evaluate the potential use of aclarubicin-loaded gelatin microspheres as an intravascular biodegradable drug delivery system for the regional cancer therapy. The diameter of the microspheres prepared by water in oil emulsion polymerization could be controlled by adjusting the stirring rate in the range of 10-50 $\mu$m : D(in $\mu$m) = -73.8 log (rpm) + 262.7. The addition of proteolytic enzyme increased the in vitro aclarubicin release but it did not change the amount of the initial burst release which reached about 45%. Microspheres injected intravenously into the mouse tail vein embolized only to the lung when observed by fluorescence microscopy. From histological examination following injection of gelatin microspheres into mouse femoral muscle, mild inflammation was observed from the appearance of neutrophils after 2 days and rapid repair process was confirmed thereafter. Biodegradation process of gelatin microspheres lodged on the pulmonary capillary bed was followed up by microscopic observation; degradation was taking place by about 36 hrs, followed by severe damage on the spheerical shape and microspheres was no longer found 10 days after injection.

• Journal of Microbiology and Biotechnology
• /
• v.25 no.2
• /
• pp.234-237
• /
• 2015

In this study, we developed lysosome-alginate beads for application as an oral drug delivery system (ODDS). The beads harboring lysosomes, which have antimicrobial activity, and various concentrations of alginate were characterized and optimized. For application as an ODDS, pH-dependent lysosome-alginate beads were generated, and the level of lysosome release was investigated by using antimicrobial tests. At low pH, lysosomes were not released from the lysosome-alginate beads; however, at neutral pH, similar to the pH in the intestine, lysosome release was confirmed, as determined by a high antimicrobial activity. This study shows the potential of such an ODDS for the in vivo treatment of infection with pathogens.

• YAKHAK HOEJI
• /
• v.38 no.6
• /
• pp.654-663
• /
• 1994

Lipiodol-anticancer suspensions containing fluorouracil, tegafur, mitomycin C, methotrexate, or adriamycin were prepared by Shinohara method using aluminum monostearate as a dispersing stabilizer. Lipiodol-suspension showed thixotropic property when the concentration of aluminum monostearate was above 2%. Observed thixotropic area which reflects the extent of thixotropic breakdown indicated that the thixotropic property of Lipiodol-suspensions maintained for six weeks in a refrigerator$(4^{\circ}C)$. Lipiodol-anticancer suspensions containing 2% aluminum monostearate maintained a more stable suspension system compared with simple mixtures and Lipiodol-anticancer suspensions without aluminum monostearate. As the concentration of aluminum monostearate increased, the drug release from Lipiodol-anticancer suspensions was more retarded.

• Proceedings of the KIEE Conference
• /
• 2015.07a
• /
• pp.1544-1544
• /
• 2015

재료의 종류 및 특성에 따른 전기 반응 약물방출 특성을 확인하기 위하여 전압을 이용한 약물방출 시스템을 설계 하였으며 각각의 재료의 특성에 따른 약물방출 특성을 확인하였다. 약물방출은 활성탄소섬유에 친수성 관능기를 도입할 경우 방출되는 약물의 양이 37% 감소하였다. 한편 PVA에 카본블랙을 첨가하여 전도성을 향상 시킨 경우 11%의 약물만을 방출하던 PVA가 대부분의 약물(98%)을 방출하였다.

• Journal of Pharmaceutical Investigation
• /
• v.22 no.1
• /
• pp.1-10
• /
• 1992

The use of erythrocyte as drug carrier has been reviewed, Carrier erythrocytes have proven to offer many advantages for delivery of therapeutic agents, especially in the treatment of inherited enzyme deficiency and cancer. Carrier erythrocytes are biodegradable and nonimmunogenic. Encapsulated drugs may be protected from premature degradation, inactivation and excretion. Carrier erythrocytes may be used as a slow-release system. Targeting of encapsulated drugs directly to a site of action is another possibility. Methods for encapsulating drugs into erythrocytes, the fate of carrier erythrocytes in vivo, the strategies of targeting carrier erythrocytes to special organs and in vivo applications of erythrocytes have been discussed. The encapsulation of drugs in erythrocytes has shown attractive possibilites in future use.

• Journal of Pharmaceutical Investigation
• /
• v.24 no.3
• /
• pp.167-176
• /
• 1994

The microcapsules of amoxicillin using stearyl alcohol and polyethyleneglycol 8000 (PEG 8000) were prepared by a emulsion melted-cooled process in water phase. The size distribution, dissolution test, observation with SEM and in vivo test were investigated. The microcapsules obtained were spherical, uniform and free flowing particles. The release of drug from microcapsule was increased in proportional to the content of PEG 8000. As the PEG 8000 content increased, the particle size of microcapsule was decreased. Sanning electron micrograph study revealed that microcapsules had comparatively rough surfaces as drug content was increased. The $AUC_{0-12}$ after administration of amoxicillin microcapsules was more increased 40% as compared with the AUC after administration of amoxicillin powder in rabbits.

• YAKHAK HOEJI
• /
• v.33 no.6
• /
• pp.324-332
• /
• 1989

Drug release from sulfanilamide granules coated with a polyelectrlyte complex of sodium tripolyphosphate and chitosan was studied. The coating film thickness increased with increasing concentration of chitosan in the coating solution and the drug release rates of the coated granules were significantly reduced comparing with those of the uncoated granules. $T_{50%}$ of the uncoated granules was 6 minutes, but those of the granules coated with chitosan-sodium tripolyphosphate from 0.5, 0.7, and 0.9% (w/v) chitosan-HCl solution were 27, 135, and 180 minutes, respectively in distilled water. In dissolution medium at pH 6.8, $T_{50%}$ of the uncoated granules was 4 minutes, but those of the granules coated with chitosan-sodium tripolyphosphate from 0.5, 0.7, and 0.9(w/v)% chitosan-HCl solution, were 32, 135, and 160 minutes, respectively.

• Archives of Pharmacal Research
• /
• v.18 no.1
• /
• pp.18-21
• /
• 1995

Poly(ethylene glycol)(PEG) macrocers teminated with acrylate groups and semi-interpenetrating polymer networks (IPNs) composed of poly-.epsilon.-capolactone(PCL) and PEG macromer were syntheswized with the aim of obtaining a bioerodible hydrogel that could be used to release drugs for implantable delivery system. Polymerization of PEG macromer resulted in the formation of cross-linked gels due to the multifunctionality of macromer. Non-crosslinked PCL chains were interpenetrated into the cross-linked three-dimensions networks of PEG. The IPNs, largw drug loading lower concentration of PEG macromer in the IPNs concentration and the higher molecular weight of PEG macromer. Also, 5-FU was more fast released than hydrocortisone to the increased water solubility.