• Macromolecular Research
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• v.17 no.12
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• pp.956-962
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• 2009

We investigated the effect of two nonlamellar-prone lipids, phosphatidylethanolamine (PE) and dioleoylglycerol (DOG), on the efficiency of protein encapsulation in liposomes. When the phosphatidylcholine (PC) matrix was replaced with PE or DOG during liposome formulation, the amounts of glutathione S-transferase and bovine serum albumin entrapped in the vesicles increased with increasing PE or DOG concentration. The presence of PE and DOG synergistically affected protein entrapment. These results suggest that protein encapsulation can be enhanced by the presence of nonlamellar lipids and/or lipid-induced membrane properties.

• Journal of Dairy Science and Biotechnology
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• v.25 no.2
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• pp.5-10
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• 2007

Ultrasonication was employed to prepare solid lipid nanoparticles (SLN) for smart probiotic nanoparticles as a nanofood. The model probiotic material, lactocin from Lactobacillus plantarum (CBT-LP2), was incorporated into SLN. The CBT-LP2 loaded SLN (CBT-LP2-SLN) were spherical in the photograph of scanning electron microscope (SEM). The particle size measured by laser diffraction (LD) was found to be $97.3{\pm}8.2nm$. Zeta potential analyzer suggested the zeta potential of LP-SLN was $-29.36{\pm}3.68$ mV in distilled water. The entrapment efficiency (EE%) was determined with the sephadex gel chromatogram and high-performance liquid chromatogram (HPLC), and up to 90.59% of nanofood was incorporated. Stability evaluation showed relatively long-term stability with only slight particle growth (P>0.05) after storage at room temperature for 4 weeks. Therefore, ultrasonication is demonstrated to be a simple, available and effective method to prepare high quality SLN loaded probiotic material.

• Bulletin of the Korean Chemical Society
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• v.32 no.3
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• pp.956-960
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• 2011

The objective of this investigation was to develop nanostructured lipid carriers (NLCs) of tacrolimus by the hot homogenization technique by sonication. NLCs are commonly prepared by emulsification and lyophilization. The feasibility of fabricating tacrolimus-loaded NLCs was successfully demonstrated in this study. The developed NLCs were characterized in terms of their particle size, zeta potential, entrapment efficiency (EE) of tacrolimus, and morphology. Studies were conducted to evaluate the effectiveness of the NLCs in improving the penetration rate through hairless mouse skin. Tacrolimus-loaded NLCs were found to have an average size of $123.4{\pm}0.3\;nm$, a zeta potential of $-24.3{\pm}6.2\;mV$, and an EE of 50%. In vitro penetration tests revealed that the tacrolimus-loaded NLCs have a penetration rate that is 1.64 times that of the commercial tacrolimus ointment, Protopic$^{(R)}$.

• Journal of Industrial and Engineering Chemistry
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• v.67
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• pp.326-332
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• 2018

In this study,the result shows that polyvinyl alcohol-sodium alginate (PVA-SA) gel bead crosslinked with sodium sulfate are better among the different methods by comparing the relative mechanical strength, mechanical strength swelling and expansion coefficient of beads in water. Subsequently, anammox biomass entrapment by PVA-SA gel was introduced into continuous stirred tank reactor (CSTR). After 24 operation days, the nitrogen removal efficiency achieved 60%, while the nitrogen loading rate (NLR) was $0.14kgN/m^3/d$ and the experiment data indicated that PVA-SA gel bead crosslinked with sodium sulfate can be used to initiate anammox process. Furthermore, it is an alternative for culturing anammox in a long-term operation.

• Applied Chemistry for Engineering
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• v.24 no.2
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• pp.132-137
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• 2013

The liquid crystal form with phosphatidylcholine contents containing in the hydrogenated lecithin was confirmed. Composition ingredients of the liquid crystal vesicle were phospholipid, ethanol and water and the rosmarinic acid was encapsulated as index material. The mean particle size of the liquid crystal vesicle appeared to form various particles form 480 nm to $3{\mu}m$ depending upon the lipid composition and ultrasonic handling time. The liquid crystal vesicle compared with the liposome showed a very high encapsulation efficiency. The quantity of liquid crystal vesicle increased with respect to the increased quantity of lipid contents in the hydrogenated lecithin. The result from release experiments of the liquid crystal vesicle containing rosmarinic acid showed that the liquid crystal vesicle releases much less than that of liposome.

• Journal of Pharmaceutical Investigation
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• v.31 no.1
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• pp.43-47
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• 2001

Sterically stabilized liposomes (SSL) have been introduced for longer circulation in blood than conventional liposomes (CL). However, there are a couple of problems in SSL preparation due to the instability of phospholipid and the degradation of drug in aqueous conditions. To solve these problems, it is necessary to go through lyophilization process. Therefore, in this study, effects of lyophilization on SSL were evaluated for physical characteristics changes upon rehydration of lyophilized SSL such as the particle size, efficiency of drug entrapment, turbidity and drug release. SSL containing streptozocin, a water-soluble anticancer drug as a model compound, were prepared with DSPC and DSPE-PEG 2000. The size was controlled to 100 nm by extrusion with polycarbonate membrane, and sucrose was used as a cryoprotectant for lyophilization at the 1:3 (lipid:sucrose) ratio. Upon rehydration of lyophilized SSL, the average size was in the range of $50{\sim}200\;nm$ which is adequate for longer circulation in blood, and the encapsulation efficiency was kept as its initial state. Rehydrated SSL were not adsorbed to rat plasma protein and revealed a similar drug release profile to that of fresh SSL before lyophilization. Therefore, lyophilization could be introduced efficiently to overcome aqueous instability problems of SSL.

• Journal of Microbiology and Biotechnology
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• v.12 no.1
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• pp.137-141
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• 2002

Anabaena variabilis ATCC 29413 grew in chromium (Cr) containing Chu-10 (basal) and nitrate-supplemented media, and the growth of the organism in $100{\mu}M$ chromium was found to be 50% of that in control medium. The growth in nitrate $({NO_3}^-)$ supplemented cultures was better as compared to cultures grown in basal medium. Free cells from basal and nitrate-supplemented media removed 5.2 and 7.4 nmol of chromium $mg^{-1}$protein in 8 h, respectively, from the medium containing $30{\mu}M$ chromium. The efficiency of chromium removal increased 7-fold in imidazole buffer (0.2 M, pH 7.0). A cell density equivalent to $100{\mu}g$ protein $ml^{-1}$ was found to be optimum for maximum Cr removal. Entrapment of cells in calcium-alginate beads did not affect the rate of Cr uptake by the cells. The efficiency of the laboratory-scale continuous flow bioreactor $(12.5{\times}2cm)$ loaded with alginate-immobilized cells (10 mg protein) and fed with $30{\mu}M$ chromium solution was compared at different flow rates. The efficiency of the bioreactor varied with flow rates. In terms of percent removal of Cr from influent, a flow rate of 0.1 ml $min^{-1}$ was found to be optimum for 6 h (54% Cr removal efficiency). Maximum amount of Cr (883 nmol) was removed by the cells in 3 h at a flow rate of 0.5 ml $min^{-1}$. The potential use of A. variabilis in removing Cr from industrial effluents is discussed.

• KSBB Journal
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• v.23 no.5
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• pp.452-459
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• 2008

To obtain maximal efficacy with minimal systemic side-effects, many studies have been carried out to achieve the controlled release of 5-fluorouracil (5-FU). In this study, biodegradable poly(L-lactide) (L-PLA) microparticles containing 5-FU were prepared by a process, called aerosol solvent extraction system (ASES), utilizing supercritical carbon dioxide. The effects of various organic solvents, drug/polymer feeding ratio, polymer molecular weight, and blending with the same polymers with different molecular weights on the formation of 5-FU loaded microparticles were investigated under a predetermined operating condition from our previous study. The drug recovery, entrapment efficiency, and in vitro drug release kinetics were determined by HPLC assays. The drug recovery obtained from the ASES process was found to be very high, whereas the drug entrapment efficiency was considerably low in all the experiments due to the poor affinity between L-PLA and 5-FU. These results indicated that the precipitation rate of L-PLA might be quite different from that of 5-FU so that there was little chance to form 5-FU loaded L-PLA microparticles.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.41 no.2
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• pp.105-112
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• 2015

Resveratrol is a natural polyphenol. It protects skin from skin injury, ultraviolet radiation and pathogenic attack. This study is to find the optimum condition for the preparation of ethosome loading amount of resveratrol in ethosome. Ethosomes were prepared by modified hydrated liquid crystal method. Investigation of factors affecting the entrapment efficiency and particle size of ethosomes was carried out. The particle size of ethosome were measured by particle analyzer. The loading efficiency of resveratrol in ethosome was measured by HPLC. The particle sizes were 111.2 ~ 112.8 nm and the loading efficiency of resveratrol was 81.25 ~ 88.75%. The optimum conditions for the preparation of ethosome was obtained from of lecithin : resveratrol : cholesterol : ethanol at a weight ratio of 2.0 : 0.08 : 0.05 : 20.0.

• Journal of the Korean Applied Science and Technology
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• v.33 no.3
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• pp.428-434
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• 2016

In this study, benzyltrialkylammonium chlorides with different alkyl chain length were synthesized and applied to liposome. Prepared cationic surfactant embedded liposomes were measured particle size, zetapotential, release property and antibacterial activity. The average particle size of liposomes was 120~140 nm. As alkyl chain length was increased, the liposome size was increased. Zetapotential for the solution of liposomes added cationic surfactants were in the range of +80~90 mV. In release test, collagen release rate could be controlled by alkyl chain length. liposome embedded long alkyl chain surfactant had enhanced sustained release property. Entrapment efficiency of hydrophilic collagen were 25.9~27.5%.