• 공업화학
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• 제22권3호
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• pp.272-276
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• 2011

본 연구는 아가로스 겔을 이용하여 금속성과 반도체성 단일벽 탄소나노튜브의 분리실험을 수행하였다. 아가로스의 농도, 분산제인 SDS (sodium dodecyl sulfate)의 농도, 아가로스 용액의 pH에 따른 단일벽 탄소나노튜브의 분리에 대한 영향을 고찰하였다. UV-vis-NIR 분광 분석으로부터 용액상의 아가로스 농도가 증가함에 따라 원심분리에 의해 추출된 상층부에서 금속성 탄소나노튜브의 비율이 증가하였지만, 분리된 탄소나노튜브의 전체적인 농도는 감소하였다. 분산제인 SDS 농도가 증가할수록 금속성 탄소나노튜브와 SDS와의 화학적 친화성으로 인해 상층부에서 금속성 탄소나노튜브의 비율이 증가하였으며, 아가로스 용액의 pH가 8.2일 때 금속성 탄소나노튜브의 비율이 최대 58.4%까지 증가하였다.

• 한국수산과학회지
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• 제44권6호
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• pp.635-643
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• 2011

Agar was prepared from Gelidium amansii collected from Jeju Island, South Korea. This agar preparation has high gel strength and low sulfate content compared with G. amansii agar from Morocco. Accordingly, agarose was made from the Jeju agar through the consecutive refining processes of dimethyl sulfoxide (DMSO) extraction and ethylene diamine tetra acetic acid (EDTA) washing. The physicochemical properties of the resulting agarose were compared with those from agarose prepared using only DMSO extraction. Consecutive DMSO extraction and EDTA washing more strongly affected the physicochemical properties of the agarose (purified agarose) compared with the use of DMSO extraction alone. These properties were similar to those of commercial agarose used for electrophoresis. In DNA electrophoresis, the separation and movement speed of the purified agarose were similar to those of the commercial agarose. In a $^{13}C$ NMR analysis, the purified agarose exhibited the same carbon peak as the commercial agarose. When observed under scanning electron microscopy, the agar had an even and smooth surface without irregularities or pores, and the purified agarose had a wide surface area with a large number of pores; the commercial agarose had an irregular surface that would allow the solvent to easily permeate. These results illustrate that the physicochemical properties of agarose prepared from DMSO extraction and EDTA washing were more effective than those observed after DMSO extraction alone; thus, these processes used in succession will be useful in agarose industries.

• 한국정밀공학회지
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• 제26권3호
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• pp.137-143
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• 2009

It has been reported that mechanical stimulation takes a role in improving eel/ growth in skeletal system. Various research groups have been showed their own bioreactors which stimulate cell-seed three-dimensional scaffold. In this study, we hypothesized that the various conditions of mechanical stimulation would affect cell growth and proliferation. To prove our hypothesis, we designed a custom-made bioreactor capable of applying controlled compression to cell-encapsulated scaffolds. This device consisted of a circulation system and a compression system. Each parts of the bioreactor was fabricated using the rapid prototyping technology By using the rapid prototyping technology, we can modify and improve the bioreactor very rapidly For dynamic cell-culture, cell-encapsulated agarose gel was fabricated in 2% concentration. We performed dynamic cell-culture using this agarose gel and developed bioreactor in 3 days.

• BMB Reports
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• 제38권6호
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• pp.763-765
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• 2005

A new simplified procedure for identifying human plasmin was developed using a DTT copolymerized agarose stacking gel (ASG) system. Agarose (1%) was used for the stacking gel because DTT inhibits the polymerization of acrylamide. Human plasmin showed the lowest activity at pH 9.0. There was a similar catalytically active pattern observed under acidic conditions (pH 3.0) to that observed under alkaline conditions (pH 10.0 or 11.0). Using the ASG system, the primary structure of the heavy chain could be established at pH 3.0. This protein was found to consist of three fragments, 45 kDa, 23 kDa, and 13 kDa. These results showed that the heavy chain has a similar structure to the autolysed plasmin (Wu et al., 1987b) but there is a different start amino acid sequence of the N-termini.

• Bulletin of the Korean Chemical Society
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• 제18권11호
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• pp.1135-1137
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• 1997

• Bulletin of the Korean Chemical Society
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• 제13권2호
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• pp.208-210
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• 1992

• 미생물학회지
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• 제23권1호
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• pp.13-19
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• 1985

제한효소 Acc I을 정제하고 그 효소적 특성을 연구하였다. 300g(wet weight)의 Acinetobacter calcoaceticus 로부터 얻은 crude extract를 sample로 하여 ammonium sulfate fractionation을 거쳐 Heparin-agarose, DEAE-se-phades, Affi,-gel Blue, phosphoceIIulose, hydroxylapatite의 순서로 chromatography를 수행한 결고 0 .28mg의 AccI 제한효소를 얻었다. 효소의 specific activity는 mg당 $1.1{\times}10^{s}$ unit 이었다. 정제된 Acc [제한효소는 10% SDS-polyacrylamide gel electrophoresis에서 한개의 band로 나타났으며 그 분자량은 45,000~1,000이었다. 이 효소는 $MgCl_2$ 존재하에, pH 8.0에서 11.0사이에서 최대의 활성을 보였다. NaCl은 이 효소의 활성에는 필요하지 않았으나 150mN이상에서는 급격한 효소 활성의 감소가 있었다.

• 한국가시화정보학회:학술대회논문집
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• 한국가시화정보학회 2007년도 추계학술대회
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• pp.88-91
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• 2007

Animal cells show different behaviors in response to the mechanical properties of the substrates. We hypothesize that the rigidity of the substrates also affects the bacterial motility and controls the colony dynamics. It is found that the colony size of Escherichia colis and Bacillus subtilis grown on the agar plates is correlated with agarose gel concentrations and thus with the substrate rigidity. High- resolution microscopic imaging reveals that bacteria in single colonies form different aggregation patterns on the agar plates with varying gel concentration. We measured the apparent diffusion coefficients in the agarose gel plates made with different gel concentrations. Mathematical modeling and quantitative imaging of dye dispersion in the agar plates suggest that there is a close connection between the diffusion rate and the colony size. Nanoscale pore structures and kinetic constraints in the porous media may have an effect on bacterial colony dynamics.

• 미생물학회지
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• 제25권1호
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• pp.73-79
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• 1987

A restriction endonuclease, Kpn I has been isolated from Klebsiella pneumonia. Cells were broken by sonication. After ultracentrifugation the supernatant containing Kpn I activity was further purified by Sepharose-6B gel filtration, DEAD-Cellulose, Heparin-Agarose, and Aminohexyl-Agarose column chromatography. Final enzyme preparation was essentially free of contamination exonuclease and phosphatase, as judged by ligation-recut test. Total activity of the enzyme recovered from 10 grams of cells was $4.7\times 10^5$ units.

• 한국동물학회지
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• 제29권4호
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• pp.283-293
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• 1986

사람의 alpha-fetoprotein(AFP)에 대한 모노클론 항체의 생산 및 분석을 위하여, 태아조직을 재료로 추출법, DEAE-cellulose 및 concanavalin A-Sepharose, Cibacron blue F3GA-agarose, immunoadsorbent column등의 흡착크로마토그라피법에 의해 AFP를 분리하였다. 총 534g의 태아조직에서 AFP의 量은 8.76 mg으로서 순수분리되었음을 확인하였다.