• Polymer(Korea)
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• v.36 no.4
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• pp.420-426
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• 2012

In this study, we prepared polymer micelles containing quercetin and rutin, known as antioxidants, using poly(${\varepsilon}$-caprolactone)-b-poly(ethylene glycol), and evaluated in vitro skin permeation of the active materials. Quercetin and rutin loaded micelles were characterized by DSC (differential scanning calorimetry), HPLC (high performance liquid chromatography) and DLS (dynamic light scattering) measurements. The particle size of the polymer micelles increased in a concentration dependent manner (0.5~2.0% PCL-b-PEG). The Zeta potential of quercetin and rutin loaded micelles remained constant. To evaluate the skin penetration of PCL-b-PEG micelles, Franz diffusion cell experiment was performed. The aqueous solutions of quercetin and rutin were used as the control groups. Quercetin and rutin loaded PCL-b-PEG micelles showed more efficient skin permeation than the control groups. Safety assessment (patch test) of quercetin and rutin loaded PCL-b-PEG micelles on skin was performed to test application possibility of the polymer micelles to cosmetics. Any adverse symptoms were not observed.

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

• Journal of electromagnetic engineering and science
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• v.14 no.4
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• pp.387-392
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• 2014

In this paper, a size-reduced Wilkinson balun with wide harmonic-suppressed band is presented. An accurate analysis of the parallel coupled line with an open stub (PCL-OS) is carried out. The PCL-OS structure shows excellent low pass filter and harmonic-suppression characteristics, which is useful for designing a low pass filter unit cell (LUC) with a reduced size. The designed Wilkinson balun at a 2.45 GHz center frequency not only shows an excellent harmonic suppression including the 5th harmonics up to 14 GHz over 15 dB, but it also has an area reduced to 48% of the conventional one.

• Macromolecular Research
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• v.15 no.7
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• pp.688-692
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• 2007

The hydrogen-bonding induced alternating multilayer thin films of dendrimers and block copolymer micelles were demonstrated. The block copolymer micelles derived from amphiphilic poly(2-ethyl-2-oxazoline)block-$poly({\varepsilon}-carprolactone)$ (PEtOz-PCL) in aqueous phase have a core-shell structure with a mean hydrodynamic diameter of 26 nm. The hydrogen bonding between the PEtOz outer shell of micelle and the carboxyl unit of poly(amidoamine) dendrimer of generation 4.5 (PAMAM-4.5G) at pH 3 was utilized as a driving force for the layerby-layer alternating deposition. The multilayer thin film was fabricated on the poly(methyl methacrylate) (PMMA) thin film spin-coated on silicon wafer or glass substrate by the alternate dipping of PEtOz-PCL micelles and PAMAM dendrimers in aqueous solution at pH 3. The formation of multilayer thin film was characterized by using ellipsometry, UV-vis spectroscopy, and atomic force microscopy. The PEtOz outer shell of PEtOz-PCL micelle provided the pH-responsive hydrogen bonding sites with peripheral carboxylic acids of PAM AM dendrimer. The multilayer thin film was reversibly removed after dipping in aqueous solution at $pH{\geq}5.6$ due to dissociation of the hydrogen bonding between PEtOz shell of PEtOz-PCL micelle and peripheral carboxyl units of PAMAM dendrimer.

• Korean Journal of Plant Resources
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• v.25 no.4
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• pp.372-378
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• 2012

Xanthium sibiricum using extracts antioxidant activity and antimicrobial activity were analyzed and the following results were obtained. Antioxidant activity using DPPH as a VLC column fractionation experiments XS-5 (water fraction of Xanthium sibiricum) concentration in the 500 ${\mu}g/ml$ to 87.53 percent in the highest antioxidant activity was found, VLC fractionation in XS-3-2 (eluted with chloroform/methanol 7~10%) concentration of 500 ${\mu}g/ml$, showed the antioxidant activity of 78.72%. The antioxidant activity measured by PCL XS-1 (n-hexane fraction of Xanthium sibiricum) XS-5 (water fraction of Xanthium sibiricum) and 13.32 nmol open column XS-3-2 (eluted with chloroform/methanol 7~10%) showed antioxidant activity with 14.34 nmol. The antimicrobial activity against Candida albicans XS-2 (methlene chloride fraction fo Xanthium sibiricum) is the concentration of 500 ${\mu}g$/disc 1 mm of the clean zone was formed. XS-3 (ethanol fraction fo Xanthium sibiricum) in the antioxidant activity using DPPH and PCL had higher antibacterial activity was low.

• Polymer(Korea)
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• v.32 no.5
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• pp.458-464
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• 2008

A successful scaffold should have a highly porous structure and good mechanical stability. High porosity and appropriate pore size provide structural matrix for initial cell attachment and proliferation enabling the exchange of nutrients between the scaffold and environment. In this paper the highly porous scaffold of poly(${\varepsilon}$-caprolactone) electrospun nanofibers could be manufactured with an auxiliary electrode and chemical blowing agent (BA) under several processing conditions, such as the concentration of PCL solution, weight percent of a chemical blowing agent, and decomposition time of a chemical blowing agent. To attain stable electrospinnability and blown nanofiber mats having high microporosity and large pore, a processing condition, 8wt% of PCL solution and 0.5wt% of a chemical blowing agent under $100^{\circ}C$ and decomposition time of $2{\sim}3\;s$, was used. The growth characteristic of human dermal fibroblasts cells cultured in the mats showed the good adhesion and proliferation on the blown mat compared to a normal electrospun mat.

• Polymer(Korea)
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• v.27 no.5
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• pp.449-457
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• 2003

The purposes of this work were the producing of a biodegradable poly($\varepsilon$-caprolactone) (PCL) / poly(ethylene oxide) (PEO) microcapsule and the analyzing of form and features for the manufacturing conditions which could be observed in a prospective drug delivery systems through drug release. The effects of emulsifier, emulsifier concentration, and stirring rate for the diameter and form of the microcapsules were observed using image analyzer and scanning electron microscope. The role of interfacial adhesion between PCL/PEO and drug was determined by contact angle measurements, and the drug release test of the microcapsules was characterized by UV/vis. spectra. As a result, the microcapsules were made in spherical fonns with a mean particle size of 170 nm∼68 $\mu$m. And the work of adhesion between water and PCL/PEO increased with increasing the content of PEO, probably due to the increased the hydrophilicity. It was also found that the drug release rate from the microcapsules significantly increased with increasing the content of PEO, which could be also attributed to the increasing of the hydrophilic groups or the degree of adhesion force at interfaces.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.05a
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• pp.133-136
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• 2008

In this paper, the parallel coupled line(PCL) band-pass filter satisfying IEEE 802.11a (a:$5.15{\sim}5.25$, b:$5.25{\sim}5.35$, c:$5.725{\sim}5.875$ [GHz]) has been designed for 5[GHz]band W-Lan RX-System applications. The designed PCL Band-Pass filter is of advantage to make a design formula that is small, light and approximate accuracy. It choose a microstrip plane figure because it is possible that a multiplicity of resonator was designed. It was shown that bandwidth was 14% from 5.15GHz to 5.92GHz at the -3dB designed filter. As a result, it is enough to use the designed filter at W-LAN RX-system of the 5GHz band.

• Journal of the Korean Arthroscopy Society
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• v.2 no.2
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• pp.135-140
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• 1998

From 1989 to 1994, authors have reconstructed the posterior cruciate ligament(PCL) in 51 knees with an autogenous central one-third of the patellar tendon by transtibial two tunnel technique, but there were not a few cases of unfavorable results. So from January 1995, we have reconstructed the PCL deficient knees by "modified tibial inlay technique" to avoid the grafted tendon abrasion at the posterior opening of the tibial tunnel(killer turn). Purpose of this study was to compare the results of two surgical techniques and what its advantages and disadvantages are. We could follow up 39 cases of transtibial two tunnel techique group(group A) more than one year, average being 23.7 months and 21 cases of modified tibial inlay technique group(group B) more than 12 months, average being 14.7 months. The clinical results were evaluated by the OAK knee scoring system ($M{\ddot{u}}ller$'s criteria) and the posteror stress roentgenography (push view) with Telos stress device compared with the uninjured knees. The arthroscopic second-look findings were also evaluated. In group A : The $M{\ddot{u}}ller$'s knee score was average 80.1 points, the posteror displacement in push view was average 4.4mm at the last follow up. There were 17 cases(44%) of unfavorable results which showed unstable posterior displacement more than 4mm compared with the uninjured knee in push view. Among the 19 cases of arthroscopic second look examinations, nearly normal PCL appearances of the grafted tendons were noted only in 9 cases(47%). In group B : The $M{\ddot{u}}ller$'s knee score was average 86.7 points, the posterior displacemnet in push view was average 3.6mm at the last follow up. There were 5 cases(23.8%) of unfavorable results which showed unstable posterior displacement more than 4mm compared with the uninjured knee in push view but 4 out of 5 cases showed 6mm posterior displacement in push views. Among the 7 cases of arthroscopic second-look examinations, 6 cases(86%) showed nearly normal PCL appearances of the grafted tendons. In modified tibial inlay technique of PCL reconstruction, it was easier to pull out the BPTB and in cases of remained laxed meniscofemoral ligament it was easier to preserve the remained structures than transtibial two tunnel technique. We expect the "modified tibial inlay technique" may solve the problem of grafted patellar tendon abrasion at the posterior orifice of tibial tunnel and may contribute to the successful PCL reconstruction.

• Journal of Microbiology and Biotechnology
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• v.21 no.1
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• pp.28-36
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• 2011

Diblock copolymers composed of poly(${\varepsilon}$-caprolactone) (PCL) and poly(N,N-dimethylamino-2-ethyl methacrylate) (PDMAEMA), or methoxy polyethylene glycol(PEG), were synthesized via a combination of ring-opening polymerization and atom-transfer radical polymerization in order to prepare polymeric nanoparticles as an antifungal drug carrier. Amphotericin B (AmB), a natural antibiotic, was incorporated into the polymeric nanoparticles. The physical properties of AmB-incorporated polymeric nanoparticles with PCL-b-PDMAEMA and PCL-b-PEG were studied in relation to morphology and particle size. In the aggregation state study, AmB-incorporated PCL-b- PDMAEMA nanoparticles exhibited a monomeric state pattern of free AmB, whereas AmB-incorporated PCL-b- PEG nanoparticles displayed an aggregated pattern. In in vitro hemolysis tests with human red blood cells, AmBincorporated PCL-b-PDMAEMA nanoparticles were seen to be 10 times less cytotoxic than free AmB (5 ${\mu}g$/ml). In addition, an improved antifungal activity of AmBincorporated polymeric nanoparticles was observed through antifungal activity tests using Candida albicans, whereas polymeric nanoparticles themselves were seen not to affect activity. Finally, in vitro AmB release studies were conducted, proving the potential of AmB-incorporated PCL-b-PDMAEMA nanoparticles as a new formulation candidate for AmB.