• Macromolecular Research
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• v.14 no.3
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• pp.348-353
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• 2006

For enhancing the gene delivery efficiency of polyplexes, a new formulation was developed using PEI conjugated Pluronic F127 copolymer as an effective additive. Low molecular weight, branched polyethylenimine Mw 600 (LMW BPEI 600) was conjugated to the terminal end of Pluronic F127. The PEI-modified Pluronic copolymers formed a micellar structure in aqueous solution, similar to that of unmodified Pluronic copolymer. PEI modification of Pluronic copolymer increased the size of micelles while concomitantly raising the critical micelle concentration (CMC). The PEI-modified Pluronic copolymer was used as a micellar additive to enhance the gene transfection efficiency of pre-formulated polyelectrolyte complex nanoparticles composed of luciferase plasmid DNA and branched PEI Mw 25k (BPEI 25k) or polylysine Mw 39k (PLL 39k). The luciferase gene expression levels were significantly enhanced by the addition of the BPEI-modified Pluronic copolymer for the two formulations of BPEl and PLL polyplexes. The results indicated that the BPEI-modified Pluronic copolymer micelles ionically interacted on the surface of DNA/BPEI (PLL) polyplexes which might facilitate cellular uptake process.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.313-316
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• 2002

Effect of Pluronic F-68, a nonionic surfactant, on the extracellular production of hGM-CSF in transgenic Nicotiαna tabacum cell suspension culture was investigated. The addition of 5 g/L Pluronic F-68 did not affect the cell growth but increased the extracellular production of hGM-CSF by two-fold. This may be due to the enhanced permeability of the cell membrane by the interaction between the Pluronic F-68 and the cell membrane.

• KSBB Journal
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• v.22 no.5
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• pp.313-317
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• 2007

To enhance the growth of cryopreserved cells of transgenic Nicotiana tabacum, Pluronic F-68 was supplemented in a recovery medium during post-thaw period. As cryoprotective agents, 1 M sucrose, 0.5 M glycerol and 0.5 M dimethyl sulfoxide (DMSO) were added before freezing steps. The post-thaw growth of the cells was improved with Pluronic F-68, ranged from 0.1 to 10 g/L. The interactions of Pluronic F-68 with the cells were confirmed by the changes of hydrophobicity or permeability of the cells. Pluronic F-68 did not show any effect on the activity of $\beta$-glucuronidase (GUS) in all treatments. Therefore, the addition of Pluronic F-68 in a recovery medium was found to be beneficial to enhance the post-thaw growth of cryopreserved transgenic tobacco cells without affecting the production of recombinant protein.

• Macromolecular Research
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• v.17 no.1
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• pp.26-30
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• 2009

To modify and strengthen the properties of PHEMA hydrogel, composite hydrogels containing varying amounts of a Pluronic (PEO-PPO-PEO) component were synthesized by bulk polymerization of HEMA in the presence of Pluronic dimethacrylate under mild photo initiating conditions. The effects of the Pluronic component on gel properties were investigated by measuring the degree of swelling with its temperature responsive behavior, the mechanical properties, and the morphology of the composite hydrogels. With increased Pluronic content, the modified PHEMA hydrogels exhibited an increase in the degree of swelling, and the swelling showed an enhanced thermo-responsive behavior that was completely reversible. In addition, improved mechanical strength and the development of a microporous gel morphology were observed in hydrogels containing Pluronic.

• Journal of Microbiology and Biotechnology
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• v.14 no.6
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• pp.1129-1133
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• 2004

The effects of Pluronic F-68, a non-ionic surfactant, on the growth and physical characteristics of Digitalis lanata suspension cultures were investigated in aqueous two-phase systems (ATPSs) composed of $4.5\%$ polyethylene glycol (PEG) 20,000 and $2.8\%$ crude dextran. In the range of 0.1-10.0 g $1^{-1}$, Pluronic F-68 enhanced the maximum cell density in a medium with ATPSs, even though Pluronic F-68 did not affect cell growth in a normal growth medium. In terms of physical properties of ATPSs with cell suspension cultures, 0.2 g $1^{-1}$ of Pluronic F-68 reduced viscosity by up to $40\%$, while 0.1 g $1^{-1}$ of Pluronic F-68 significantly enhanced the oxygen transfer rate. In addition, we successfully performed aqueous two-phase cultivation in a 5-1 stirred tank bioreactor with 0.5 g $1^{-1}$ of Pluronic F-68, and discovered that cell growth in ATPSs was similar to that in normal growth medium.

• KSBB Journal
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• v.22 no.4
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• pp.207-212
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• 2007

Pluronic F-68 and oxygen vectors were applied to increase the cell growth of Angelica gigas Nakai in aqueous two-phase system (ATPS). ATPS was composed of 3.6% (w/v) polyethylene glycol (PEG) 20,000 and 2.8% (w/v) crude dextran. n-Hexadecane, n-dodecane and FC-40 were used as oxygen vectors to enhance the oxygen transfer in ATPS. With 2$\sim$10 g/L of Pluronic F-68, addition of of n-hexadecane and FC-40 significantly enhanced the oxygen transfer rate as well as the maximum cell mass in a medium with ATPS. However, n-dodecane reduced the cell growth in all treatments. Maximum cell densities were increased up to 27.5% with 10 g/L of Pluronic F-68 and up to 40.2% with 8% (v/v) n-hexadecane compared to those of the controls without Pluronic F-68 and oxygen vectors. It was confirmed that the cell growth could be increased in ATPS using n-hexadecane.

• KSBB Journal
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• v.8 no.3
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• pp.295-299
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• 1993

The effect of fungal elicitor, Pluronic F-68 and methylcellulose on suspension culture of M piperita cells was investigated in shake flasks. About a two-fold increase in oil production was observed in response to the treatment of the fungal elicitor prepared from Rhodotorula rubra. Low concentration of Pluronic F-68 or methylcellulose enhanced Peppermint cell growth at 100 rpm of agitation.

• Applied Chemistry for Engineering
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• v.20 no.6
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• pp.632-637
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• 2009

Poly(${\varepsilon}-caprolacton$)/ethyl cellulose (PCL/EC) microcapsules containing pluronic F127 were prepared by a spray drying method. The aqueous phase, 20% of pluronic F127 was dissolved in distilled water, and the organic phase, 5% of PCL and EC were dissolved in dichloromethane. The microcapsules were obtained by spray drying the water-in-oil (W/O) emulsion. According to the data of scanning electron microscopy and particle analyzer, tens of micro size microcapsules were observed. On a differential scanning calorimeter, the phase transition temperatures of microcapsules were observed and they were found around those of pluronic F127 and poly(${\varepsilon}-caprolacton$), which were the main components of the microcapsules. At the range of $30{\sim}45^{\circ}C$, temperature-dependent release properties were investigated using fluorescein isothicyanate-dextran (FITC-dextran) and blue dextran as a model drug. When the temperature was increased, the degree of release of microcapsule was also increased. FITC-dextran, the relative low molecular weight, was more released than blue-dextran.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.267-267
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• 2006

Human umbilical cord blood was stored at $4^{\circ}C$ in the Pluronic-immobilized flask as well as commercially available bio-inert flasks, and flow cytometric analysis of surface markers was performed on hematopoietic stem cells after cultivation. The number of cells expressing $CD34^{+}$ in umbilical cord blood on the Pluronic-immobilized flask was extremely higher than those obtained using other flasks. It is concluded that the flexible and hydrophilic segments of Pluronic conjugated on the flask surface are the reason for the effective preservation of hematopoietic stem cells in the Pluronic-immobilized flask.

• Journal of Pharmaceutical Investigation
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• v.31 no.1
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• pp.1-5
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• 2001

The aggregation behavior of nystatin (NYS) in the presence of pluronic F127, triblock copolymer of poly (ethylene oxide) (PEO) and poly (propylene oxide) (PPO), was measured and correlated with hemolytic activity. Antifungal activity was also studied using Saccharomyces cerevisiae as a model strain. The critical aggregation concentrations (CAC) of the drug were 50.1, 108.0, 134.2, 154.3, and $217.9\;{\mu}M$ at 0.1%, 0.5%, 1.0%, 1.5%, and 2.0% pluronic F127 solution, respectively. The levels of NYS required to start lysis of erythrocytes were about 80, 100, 125, 150, and $200\;{\mu}M$ at 0.1%, 0.5%, 1.0%, 1.5%, and 2.0% pluronic F127 solution, respectively. It was $50\;{\mu}M$ in the absence of the polymer. Minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) of NYS-pluronic F127 lyophilizate were same at $3\;{\mu}g/ml$, while MIC and MFC of pure NYS are $3\;{\mu}g/ml$ and $12\;{\mu}g/ml$, respectively. By modulating the aggregation behavior of NYS, pluronic F127 was able to reduce the toxicity of the drug without compromising the MIC and MFC.