• Microbiology and Biotechnology Letters
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• v.22 no.3
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• pp.316-321
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• 1994

Several strains capable of degrading PEGs(Polyethylene Glycols) were isolated and investigated for their biodegradation ability of PEGs. Microorganisms screened for the biodegrada- tion studies were those grown on the PEG used as a sole carbon and energy source. It was known that the number of microorganisms decreased when grown on the high molecular weight of PEG. A biodegradation of PEG was investigated with such microorganisms in the reactor and resulted in the decrease in PEG concentration meaning that PEG was degraded in the reactor. This microorganism was identified as Flavobacterium sp. The biodegradability was found to be about 18.8% for PEG-8000 and 25.4% for PEG-10,000, respectively. For the manufacture of biodeg- radable PEG film, EMAA/PEG and EAA/PEG blending ability was investigated with IR spectrum and showed that it was possible to produce blending film.

• Proceedings of the Membrane Society of Korea Conference
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• 2000.04a
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• pp.73-76
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• 2000

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.335-335
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• 2007

염료감응형 태양전지(Dye-sensitized solar cells)용 페이스트의 제조시 바인더(binder)인 폴리에틸렌 글리콜(Polyethylene glycol; 이하 PEG)의 함량변화가 염료감응형 태양전지의 에너지 변환효율에 미치는 영향을 조사하고자 하였다. PEG의 함량변화는 0-30wt%까지 변화시켰으며 그들의 표면이나 단면의 형상을 FE-SEM, AFM으로 관찰 하였고, PEG 함량변화에 따른 열적특성은 TG/DTA 결과로 조사하였다. PEG의 양이 0%에서 20wt%까지 첨가되었을 때 단락전류밀도(Isc: Short current density)는 증가되어 나타났고 PEG가 30wt%가 첨가되었을 때는 오히려 감소하는 것을 확인할 수 있으며 이것은 $TiO_2$ 입자간의 응집현상이 과도하게 진행되어 전자의 흐름을 방해한 것으로 판단된다. PEG의 함량이 20wt% 첨가되었을 때 개방전압 (Voc: Open circuit voltage)이 0.73V, 단락전류밀도는 $22.6mA/cm^2$, 필펙터는 0.55, 에너지변환효율은 9.1%로 최적의 바인더 함량을 나타내었다. 염료감응형 태양전지의 광전극 제조시 PEG 바인더의 함량 변화에 따라 일자간의 응징특성이나 기공도와 같은 표면형상, 그리고 에너지변환효율을 변화시킨다는 것을 확인할 수 있었다.

• The Korean Journal of Nuclear Medicine Technology
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• v.27 no.2
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• pp.133-136
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• 2023

Purpose: Prolactin in the blood is separated into three types, and over 90% of prolactin presents as a double monomer (23 KDa). Rarely, it can exist in the size of big prolactin (150 KDa), which is called macroprolactin and is known as an autoantibody complex. When macroprolactin accounts for more than 60% of prolactin in the blood, it is called macroprolactinemia. The presence of such macroprolactin was first reported in a patient with hyperprolactinemia but without typical symptoms. Macroprolactinemia is emerging as an important cause of idiopathic hyperprolactinemia. The polyethylene glycol (PEG) precipitation method using the property of precipitating large-molecular-weight proteins is simple and recently has been widely used as a screening test. The results are in good agreement with the results of gel chromatography. The purpose of this study was to confirm the measurement method and reference value verification of monomeric prolactin in blood prolactin using the PEG precipitation method. Materials and Methods: For 40 examinees who visited the Gangnam Center of Seoul National University Hospital in 2021, the prolactin level was verified using radioimmunoassay (RIA). For macroprolactinemia PEG precipitation method, 25% PEG (molecular weight 6000kDa) solution and serum were mixed in equal amounts in a test tube, then left at room temperature for 20 minutes and centrifuged at 4℃ for 30 minutes (1500g). The prolactin level was measured in the supernatant. Results : After confirming that more than 90% of the 40 tested samples within the reference range <25 ng/mL, the same value as the reference value for prolactin was applied. Since the concentration of monomeric prolactin in serum from which macroprolactin has been removed from blood is diluted 1:1 with PEG, our laboratory is currently reporting the result by multiplying the result by a dilution factor of 2. Conclusion: Radioimmunoassay using PEG precipitation method using the property of precipitating large molecular weight proteins is simple and effective for quantitative measurement of monomeric prolactin in blood prolactin.

• Archives of Pharmacal Research
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• v.17 no.5
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• pp.381-382
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• 1994

Administration route dependency on the distribution of PEGylated recombinant human turor necrosis factor binding protein (rhTNFbp-PEG20K dimer) was observed following a subcutaneous (sc) and an intravenous (iv) administrationin rats. ehTNFbp-PEG20K dimer is composed of two rhTNGbp molecules (molecular weight 18, 278 daltons each) joined by polyethylene glycol 2000(PEG30K). The steady state distribution volume of rhTNFbp-PEG20K was 55 m/kg and 359 ml/kg following the i.v. and s.c. administrations, respectively. These results suggest that the distribution of ehTNFbp-PEG20K is limited within the cpillary space after i.v. administration, while rhTNFbp-PEG20K can distribute into a space (35.9% of body weight) which is between extracellylar space and total body water. A lymphatic absorption may paly a role in the distribution of rhTNFbp-PEF20K dimer following the sc administration. The present study suggests that the administration route of a lartge protein molecule should be determined depedning upon target sites.

• Korean Journal of Animal Reproduction
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• v.14 no.2
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• pp.133-140
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• 1990

This study was conducted to develop a simple and efficient technique for fusing 2-cell mouse embryos to obtain tertraploid embryos. Various concentration of PEG and exposure times were compared in order to determine the best condition for fusion and subsequent of fused embryos. The results obtained were follows ; 1. The incidence of fusion induction treated with 40% PEG(70.8%) and 45%(62.7%) for 60 sec. exposure were higher than those of 40% and 45% PEG for 30 sec., 90 sec., or 120 sec. exposure group. Also, the highest incidence of fusion induction(76.9%) was achieved with 120 sec. exposure at 50% PEG concentration. 2. Fused embryos after PEG treatment were cleavaged 2-to 4-cell, 8-cell, morula and blastocyst at 20-24 hr., 30-34., 44-52 hr., respectively, and were not different from those obtained fleshly. 3. The high proportions of the embryos developed to blastocysts after blastomere fusion with 40% PEG for 60 sec., 45% PEG for 60 sec. and 50% for 120 sec. were 66.7%(42/63), 69.0%(29/42) and 32.0%(16/50), respectively, this trend indicated that the fusion rate was similar to the incidence of fused embryos forming blastocysts. 4. The cell number of blastocyst developed from fused embryos(18.7 2.6) was samller than that of untreated embryos(48.9 1.69)

• YAKHAK HOEJI
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• v.29 no.5
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• pp.234-245
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• 1985

To clarify the diffusional behavior of p-aminbenzoic acid esters in the presence of polyethylene glycol 400, cellulose membrane permeation rate, solubility and viscosity of p-aminobenzoic acid methyl ester, benzocaine and butamben were determined with PEG solutions of various concentrations. With an increase in PEG concentrations permeation rates from solutions; decreased due to an increase in viscosity of the solution. From suspensions, however, permeation rates increased due to an increase in solubility and when the initial drug concentration was constant, permeation rates were found to be greatest from the PEG-water system with the PEG concentration which transported from the solution to the suspension. Permeation rate of 4.0mg/ml p-aminobenzoic acid methyl ester was $26.51\mu$g/ml$\cdot$hr from 5g/100ml PEG solution, and that of 4.0mg/ml benzocaine was $13.17{\mu}g/ml{\cdot}hr$ from 15g/100ml PEG, solution, and that of 2.0mg/ml butamben was $3.8{\mu}g/ml{\cdot}hr$ from 10g/100ml PEG solution. Permeation rate was 7.0 fold in p-aminobenzoic acid methyl, ester and 3.5 fold in benzocaine compared to butamben.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.2
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• pp.260-267
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• 2015

We investigated the applicability of polyethylene glycol (PEG) as a plasticizer in enteric-coated soft capsules based on determination of quality characteristics according to molecular weight and concentration of enteric-coating PEG solution. There was no difference according to molecular weight of PEG, whereas a low PEG concentration in the enteric-coating solution was associated with higher whiteness index and slower disintegration time in pH 6.8 media. Brittleness was observed in the coating film at seam areas in 5% PEG enteric-coating solution after 2 weeks of storage at room temperature. The enteric-coating properties of PEG were compared with those of acetylated monoglyceride (AMG) and triacetin, which are enteric-coating plasticizers. Enteric-coated soft capsule containing PEG as a plasticizer showed a lower whiteness index and faster dissolution profile than AMG and triacetin. Moreover, enteric-coated soft capsule containing AMG and triacetin as plasticizers showed coating film brittleness at seam areas after 2 months of accelerated storage [$40^{\circ}C$, relative humidity (RH) 75%] but no difference at room temperature storage ($25^{\circ}C$, RH 60%). The present study suggests that concentration of PEG is important to determine enteric-coating quality, regardless of the molecular weight of PEG. In conclusion, PEG has potential as a plasticizer due to its transparency and storage stability in enteric-coated soft capsules.

• Macromolecular Research
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• v.14 no.1
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• pp.73-80
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• 2006

Sulfonated poly(ethylene glycol) (PEG-$SO_{3}$) grafted polyrotaxanes (PRx-PEG-$SO_{3}$) were prepared in order to utilize the unique properties of PEG-$SO_{3}$ and the supramolecular structure of PRx, in which PEG-$SO_{3}$ grafted $\alpha$-cyclodextrins ($\alpha$-CDs) were threaded onto PEG segments in a PEG-b-poly(propylene glycol) (PPG)-b-PEG triblock copolymer (Pluronic) chain capped with bulky end groups. Some of the PRx-PEG-$SO_{3}$ demonstrated a higher anticoagulant activity in case of PRx-PEG-$SO_{3}$ (P 105), and compared with the control they showed a lower fibrinogen adsorption in PRx-PEG-$SO_{3}$ (F68) and a higher binding affinity with fibroblast growth factor. The obtained results suggested that polyrotaxane incorporated with PEG-$SO_{3}$ may be applicable to the surface modification of clinically used polymers, especially for blood/cell compatible medical devices.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.447-448
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• 2010