• 농업과학연구
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• 제37권3호
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• pp.543-545
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• 2010

Apo, holo, native-type of lactoferrin showed a similar pattern of circular dichroism(CD) spectra. Lactoferrin appeared to interact more easily with negatively charged liposome than neutral liposome. Holo-type of lactoferrin showed the highest degree of leakage, whereas apo-type of lactoferrin showed the lowest level of leakage. Holo-type lactoferrin could more easily interact with phospholipid liposomes than apo-type lactoferrin, when used as an artificial membrane.

• Archives of Pharmacal Research
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• 제23권2호
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• pp.167-171
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• 2000

We have investigated the in vitro cytotoxic effect of liposome-encapsulated N-(phospho-nacetyl)-L-aspartic acid (PALA) against C-26 murine colon cancer cells, and have compared it in this regard to free PALA. Three different PALA-containing liposomal formulations using distearoylphosphatidylcholine (DSPC), distearoylphosphatidylglycerol (DSPG), and polyethyle-neglycol-derivatized distearoylphosphatidylethanolamine (PEG-DSPE) were made and their cytotoxicity was measured. In 72 hr continuous exposure experiment with C-26 cells, the 50% growth inhibitory concentration ($IC_50$) of DSPG-PALA liposome formulation was $0.09\mu\$, which showed about 65-fold more potent than unencapsulated free PALA ($5.1\mu\$). Similar degree of increase in cytotoxicity was also observed in 1 hr exposure experiment. However the $IC_50$ of PEG-DSPE-PALA liposome and DSPC-PALA liposome were $10.7\mu\$and $11.8\mu\$respectively, which showed slightly less potent than unencapsulated free PALA. Physical characteristics of PALA-liposomes, such as the size and drug:lipid ratio were also determined. In conclusion, negatively-charged DSPG-PALA liposome showed the highest cytotoxic effect among tested on the C-26 cells in vitro.

• 대한화학회지
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• 제57권5호
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• pp.634-639
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• 2013

암이나 혈관질환을 진단하기 위하여 영상의학기기들의 사용이 증가되고 있다. 영상의학기기 중 컴퓨터단층촬영(CT)은 가장 널리 이용되는 방법의 하나로서, CT를 하기 위해서는 조영제를 투여하여야 한다. 따라서, 본 연구에서는 리포솜의 표면에 금 입자를 코팅함으로써 조영제로 개발하고자 하였다. 금 입자를 코팅하기 위하여, 양이온성 리포솜을 제조하였고, 양이온성 리포솜의 표면에 음이온을 띄는 $Au^-$가 정전기적으로 코팅이 되게 하였다. 금 코팅 리포솜(GCL)의 크기는 $154.8{\pm}9.2$ nm 이었고, 표면전하는 $27{\pm}3.2$ mV 이었다. 리포솜의 형태는 주사전자현미경과 투과전자현미경으로 확인하였다. 리포솜 표면의 금 코팅 효율은 18% 였으며, MTT 분석을 한 결과, 금 코팅 과정에 대한 세포독성은 없었다. 그리고, 제조된 금 입자 코팅 리포솜을 CT로 촬영했을 경우 우수한 조영 효과를 나타냈다. 따라서 본 연구에서 제조된 GCL은 CT 조영제로서 다양한 혈관질환에 적용이 가능할 것이다.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 1996년도 정기총회 및 학술발표회
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• pp.37-37
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• 1996

Tenecin fragments are antimicrobial and antifungal peptide from Tenebrio molitor with highly positive charged amino acid residues. To elucidate their membrane selectivity and molecular mechanism, various forms of tenecin fragments were synthesized, and their interaction with acidic phospholipid, Gram (+), fungal and human erythrocyte membrane were investigated by ANTS/DPX leakage, membrane binding and fusion assay. (omitted)

• Journal of Pharmaceutical Investigation
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• 제30권2호
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• pp.127-131
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• 2000

Previously, we have reported an antitumor efficacy of liposomal N-(phosphon-acetyl)-L-aspartic acid (or PALA) in C-26 tumor bearing Balb/c mice, where PALA in liposome was administered one day after tumor inoculation. In this report, we have investigated the therapeutic potency of liposomal formulation of PALA, which was administered eight days after tumor inoculation in the same C-26 tumor bearing mice. The C-26 murine colon tumor inoculated mice were randomized for the in vivo therapy and the survival was measured after a single intraperitoneal injection of the drug. When the therapy was initiated eight days after tumor inoculation, DSPC-PALA at 150 mg/kg resulted in a significant increase in median survival time (MST) of 56% over the control group which received MES/HEPES buffer alone. However, none of the free PALA and DSPG-PALA liposome doses caused a statistically significant increase in MST over control group at the 95% confidence level. At 750 mg/kg dose, free PALA caused a marginally significant improvement in MST by 34%, but both 375 mg/kg and 150 mg/kg doses of free PALA caused only a 2% and a 4% increase in MST, respectively. These results show that PALA in neutrally charged liposome can exhibit considerably greater potency than free PALA in established C-26 tumor bearing mice.

• 한국식품과학회지
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• 제50권6호
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• pp.636-641
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• 2018

본 연구에서는 식품에 적용할 수 있는 코팅방법인 리포좀과 더블에멀션의 안정성을 연구하기 위해 기능성 아미노산인 BCAA를 함유한 리포좀과 더블에멀션을 제조하였다. 리포좀의 입자크기는 pH 7보다 pH 4에서 더 작게 나타났는데, 이는 양쪽성 이온인 BCAA가 pH 4에서는 양전하를, pH 7에서는 음전하를 띠기때문에 음전하인 레시틴과의 상호작용을 하여 그 크기에 차이가 있는 것으로 판단된다. 제타전위의 절댓값은 pH 7보다 pH 4에서 더 크게 나타나 pH 4에서 리포좀의 분산안정성이 더 높은 것으로 나타났다. 더블에멀션은 초기 입자의 크기가 $100{\mu}m$ 이내, 제타전위는 모두 절댓값이 30 mV 이상이었으나, 시간이 경과함에 따라 그 크기가 커지고, 제타전위의 절댓값은 감소하는 경향을 보였다. 리포좀과 더블에멀션의 BCAA 포집율은 모두 97% 이상이었고, 누적 방출율은 리포좀에서 더 크게 나타났으나 5일간 누적방출율은 30% 미만으로 나타났다. 따라서 리포좀과 더블에멀션은 높은 효율로 특정 기능성 물질을 안정적으로 포집한다는 특징을 가지며, 추후 계속적인 연구를 통해 이를 식품 산업에 적용할 수 있을 것으로 기대된다.

• Journal of Pharmaceutical Investigation
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• 제31권4호
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• pp.225-232
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• 2001

The present study was carried out to observe the effect of liposome dispersed gel formulation (Lipogel) on topical delivery of ascorbyl palmitate (AsP). Neutral and negatively charged MLV liposomes containing AsP were prepared with dimyristoylphosphadtidylcholine (DMPC) and dicetyl phosphate (DCP), and dispersed to poloxamer gel matrix. In the hydrolysis study in rat's skin homogenates, AsP hydrolyzed to ascorbic acid (AsA) according to the first-order kinetics with the rate constant of $2.46{\times}10^{-2}\;min^{-1}$. In the passive skin penetration study using Franz diffusion cell, lipogel systems exhibited the greater values in the flux $(J_s)$ and the amount penetrated $(Q_p)$ compared to control hydrogels containing diethyleneglycol monoethyl ether $(Transcutol^{\circledR})$ as a solubilizing agent and a penetration enhancer for AsP. The total amount penetrated $(Q_{Total})$, which is expressed as a summation of $Q_P\;and\;Q_L$, for lipogel system was about 1.4 times higher in average than that of control hydrogel. However the amount localized in the skin $(Q_L)$ was similar in both formulations. As a result, lipogel system enhanced the skin penetration of AsP, possibly due to the increase in local concentration of AsP by preferential adsorption of liposome to the skin and the enhancing effect of phospholipid in liposome composition. Moreover it was expected that the penetrated AsP would generate AsA during skin penetration by the skin esterase. In conclusion, lipogel formulation was considered as a good candidate for topical delivery of AsP.