• Journal of Electrical Engineering and Technology
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• v.4 no.3
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• pp.418-422
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• 2009

We synthesized new electroluminescence materials [(1,10-phenanthroline)(8-hydroxyquinoline)] Zn(phen)q and investigated their electron transport properties. We used Zn(phen)q and $Alq_3$ for the conductive materials and measured their electron transport properties as a function of the organic layer thickness. The difference between Zn(phen)q and $Alq_3$ as electron transporting materials suggests that the electrical properties depends on the carrier injection.

• Korean Journal of Microbiology
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• v.24 no.2
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• pp.119-126
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• 1986

A periplasmic endoprotease, named protease Pi, was purified to homogeneity from Escherkchia coli by conventional procedure with insulin as substrate. This enzyme degrades insulin and glucagon to trichloroacetic acid-soluble meterials, but shows little or no hydrolysis of bovine serum albumin, casein or globin. Its molecular weight was 110, 000 when determined by gel filtration on Sephacryl S-300 and was 105, 000 when estimated by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. Thus, it appears to be single polypeptide. This snzyme is metalloprotease, since it is completely inhibited by o-phenanthroline and can be activated by addition of divalent metal cations, such as $Mg^{2+}\;and\;Co^{2+}$. It is destinct from protease Ci, a cytoplasmic insulin degrading enzyme, since protease Pi is localized to the periplasm. Since protease Pi selectively degrades GTP cyclohydrolase I, it appears to play a role in the regulation of pteridine biosynthesis.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1042-1045
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• 2006

The electrical and optical properties of electrophosphorescent organic light-emitting diodes (OLEDs) with modified hole blocking layer (HBL) were investigated. Well-known 2,9-dimethyl-4,7- diphenyl-1,10-phenanthroline (BCP) HBL is mixed with electrophosphorescent host material (4,4'-N,N'- dicarbazole-biphenyl: CBP) or electrophosphorescent dopant material (fac-tris(2-phenylpyridine) iridium: $Ir(ppy)_3$) or both. The highest external quantum efficiency was obtained in the device with $BCP-CBP-Ir(ppy)_3$ mixed HBL and we attribute this result to the additional charge recombination in mixed-HBL.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1401-1403
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• 2005

We present that the carrier balance can be improved by doping a hole transport layer of 4,4'- bis[N-(1-napthyl)-N-phenyl-amino]-biphenyl (${\alpha}$-NPD) with a hole blocking material of 2,9-dimethyl- 4,7-diphenyl-1,10-phenanthroline (BCP). The doping leads to disturb hole transport, which can enhance the balance of electron s and holes concentration in the emitting layer, aluminum tris(8 -hydroxyquinoline) (Alq3), resulting in enhanced electroluminescence (EL) quantum efficiency for the device with the doped ${\alpha}$-NPD.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.4
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• pp.323-326
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• 2009

We have developed blue-emitting phosphorescent organic light emitting diodes (OLEDs) using 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) and tris (8-quinolinolato)aluminum ($Alq_3$) electron transport layers. As blue dopant and host materials, bis[(4,6-di-fluorophenyl)-pyridinate-N,C2']picolinate (FIrpic) and N,N'-dicarbazolyl-3,5-benzene (mCP) were used, respectively. The driving voltage, current efficiency and emission characteristics of devices were investigated. While the driving voltage was about $1{\sim}2$ V lower in the device with an $Alq_3$ layer, the current efficiency was about 66 % higher in the device with BCP electron transport layer. the blue phosphorescent OLED with BCP layer exhibited higher purity of color, resulting from a relatively weak electroluminescence intensity at 500 nm.

• Biomedical Science Letters
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• v.10 no.4
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• pp.415-420
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• 2004

Fibrinolytic substance was purified from the Wooltalikong (Phaseolus ssp.), using DEAE-cellulose chromatography, Sephadex G-150 gel-filtration, and FPLC gel-filtration. The substance has a molecular weight of 5262.70 Da as measured by MALD-TOF mass spectrometry. It has a pH optimum at pH 6.0. The fibrinolytic activity of purified substance was inhibited by EDTA and 1,10-phenanthroline and slightly decreased by PMSF and pepstatin A. It shows the maximum fibrinolytic activity at 40℃ and the substance was stable up to 50℃. The activity of the substance was increased by Zn/sup 2+/ and was totally inhibited by Hg/sup 2+/. This study revealed that Wooltalikong could be a good source of fibrinolytic products due to its small molecular size and heat-resistant ability.

• Journal of Microbiology and Biotechnology
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• v.9 no.6
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• pp.861-869
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• 1999

An extracellular protease was purified to homogeneity from the culture supernatant of psychrotrophic bacteria Bacillus sp. JH 108 using procedures including ammonium sulfate fractionation, anion exchange chromatography, gel filtration chromatography, and cation exchange chromatography. The enzyme exhibited a molecular weight of 36 kDa, an optimum pH of 8 to 9, and optimum temperature of $60^{\circ}C$. The enzyme preferentially hydrolyzed leucine at the N-terminus of peptides and thus can be classified as an aminopeptidase. It was strongly inhibited by metal chelating agents such as EDTA and l, l0-phenanthroline. The activity lost by EDTA was restored with $Zn^{2+}{\;}or{\;}Co^{2+}$. These divalent cations also stimulated the native enzyme. This suggests that the enzyme is a metalloprotease acting as a leucine aminopeptidase.

• Biomedical Science Letters
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• v.8 no.4
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• pp.245-250
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• 2002

Fibrinolytic enzyme has been purified from the edible mushroom, Tricholoma sejunctum using DEAE-cellulose chromatography, Phenyl-Sepharose chromatography and Mono-S column chromatography. The apparent molecular mass of purified enzyme was estimated to be 17100 Da by SDS-polyacrylamide gel electrophoresis and 19000 Da by gel filtration, Indicating that it was a monomer. The N-terminal amino acid sequence of the enzyme was Ala-Thr-Tyr-Lys-Ile-X-Ser-Ala-Thr-His-Gln-X-X-Leu-Val. It has a pH optimum at pH 9.5, suggested that purified enzyme was a alkaline protease. The activity of purified enzyme was inhibited by EDTA and 1,10-phenanthroline, indicating that purified enzyme is a metalloprotease. The activity of purified enzyme was increased by Zn$^{2+}$ and Co$^{2+}$, however, the enzyme activity was totally inhibited by Hg$^{2+}$.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.784-787
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• 2002

Oganic light emitting diodes (OLEDs) using PBD(2-(4-biphenylyl)-5-(4-tert-butylpheny)-1,3,4oxadiazole) as a hole blocking layer were fabricated and their device performances were investigated. The devices have a structure of glass substrate ${\setminus}$ indium tin oxide (ITO) ${\setminus}$ TPD(HTL)${\setminus}$PBD,BCP(HBL)${\setminus}$Alq3(EIL)${\setminus}$Mg:Ag(cathode). In this work Bathocuproine(BCP:2,9-Dimethyl-4,7-diphenyl-1,10-phenanthroline) and PBD which were previously known as a good ETL material were used as a HBL. By employing HBL, the luminance and quantum efficiency of OLEDs could be improved due to the increase of recombination probability of electrons and holes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.3
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• pp.493-499
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• 2000

골감소증 환자의 혈청중에 존재하는 IGFBP-5의 존재와 변화를 검토한 결과, 골감소즈 환자에서는 정상 대조군에 비해 IGFBP-5가 감소하였는데 이 변화는 IGFBP-5의 분해효소가 작용하기 때문인 것으로 나타났다. IGFBP-5에 작용하는 단백질분해효소 저해제중 metallo계인 EDTA 및 1,10-phenanthroline과 seriner계인 aprotinin, heparin, heparin cofactor 2(HC2), heparine+HC2가 IGFBP-5에 대해 저해효과가 크므로 metalloprotease이면서 serine protease의 성질을 가지는 효소들이 IGFBP-5에 작용하였다. IGF-I과 IGF-II 그리고 insulin은 효소 활성에 아무런 영향이 없었다. IGFBP-5의 zymography에서 정상인과 골감소증 환제어서 180 kDa 크기의 band가 나타났고, gelatin zymography에서 정상 대조군의 경우 66 kDa과 97 kDa 정도의 band가 확인되었고 골감소증 환자의 경우는 69 kDa의 band가 확인되었다.