• 한국정밀공학회지
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• 제28권7호
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• pp.851-858
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• 2011

Nanopositioning technologies play an important role in the progress of electronics, optics, bio-engineering and various nano-scale technologies. As a result, various practical nanopositioning methods have been successfully introduced. Flexure mechanism is a valuable method in nanopositioning because of smooth and friction-free motion and the infinitesimal movement near to sub-nm. In this study a modularized nanopositioner based on parallelogram four-bar linkage structure with right-circular flexure hinge was developed. The positioning performance of a single axis nanopositioner and a XY nanopositioner which was extended from single axis one were demonstrated using control experiments. Consequently, it was shown that the developed single axis nanopositioner possessed high performance and could be extended to various multi-axis nanopositioners.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.83-83
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• 2013

To date, various nanobiotechnologicalapproaches for biosensors and drug development have been explosively studied. Despite of successful demonstrations, the new technologies hardly enjoyed routine applications in practical nanobiomedicine. Here, researchers trained at the interface of basic sciences and engineering are expected to play critical roles. In this tutorial, I will introduce recent studies which harness graphene derivatives for developing bioanalytical platforms to quantitatively analyze various enzyme activities and biomarkers. The systems rely on attractive interaction between graphene oxide and nucleic acids or phospholipids. Recently, one of the graphene-based bioassay system was applied to anti-viral drug screening and potent hit compounds were identified to treat hepatitis C. This study clearly shows that a new nanobio-technology can be routinely implemented in drug discovery, providing many advantages over conventional methods.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.84-84
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• 2013

FcBP consisting of 13 amino acids specifically binds to Immunoglobulin G Fc domain. Initially, we utilized this peptide for preparation of antibody chip as a PEG composite for enhanced solubility. After then, the peptide conjugate was immobilized on agarose resin, resulting in highly efficient affinity column for antibody purification. The efficiency was comparable to commercial Protein A column. Recently, this peptide was conjugated with cell penetratingpeptide (CPP) on a backbone of GFP, affording antibody transducer, which carries antibody into live cells by simple mixing of antibody and the transducer in cell culture media. Antibody transduction into cells was monitored by live cell imaging. More recently, the FcBP was fused to ferritin cage, which consists of 24 ferritin protein molecules. The FcBP-ferritin cage showed greatly increased binding affinity to human IgG. Its binding was analyzed by QCM and SPR analysis. Finally, it was selectively delivered by Herceptin to SKBR3, a breast cancer cell, over MCF10A, non-tumorigenic cells.

• Mass Spectrometry Letters
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• 제2권3호
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• pp.73-75
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• 2011

In the collisionally-activated dissociation of the proton-bound cluster ions of DNA base guanine (G) and cytosine (C), $G{\bullet}{\bullet}H^+{\bullet}{\bullet}C$, the abundance of [$CH^+$] ions was found to be higher than that of [$GH^+$] despite the fact that G has a higher proton affinity than C. This unexpected observation seems to demonstrate another example that the simple kinetic method scheme does not work. We suggest that a kinetic factor or detailed dynamics governing the proton transfer and dissociation should be carefully considered in the applications of the kinetic method to the proton affinity measurements.

• 한국동물생명공학회지
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• 제35권2호
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• pp.113-118
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• 2020

Hepatic stellate cells (HSCs) play essential roles in normal and pathophysiological function in liver. In steady state, HSCs contribute to retinoid storage, immune tolerance, and extracellular matrix (ECM) homeostasis. Upon liver injury, they become activated and lead to morphological and functional changes. Studies have demonstrated that activation of HSCs by various stimuli such as toxins, microbial infection, or metabolic overload can promote the fibrotic changes in liver by production of ECM. Herein, we provide current knowledge about the basic characteristics of HSCs and the mechanism by which they are activated.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.357-357
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• 2006

Many industrial sources of proteins can be used as raw materials to produce films, molded materials, and various hollow items either by "casting" techniques or by "thermoplastic processing". Combining proteins with natural fibbers, paper or biodegradable polyesters is very promising to form biodegradable composites witch take advantage of the barrier and mechanical properties of each component. Using nano-fillers to form nanocomposites has also been shown to be interesting to improve properties. Production, with low transformation cost, of protein based materials to form biodegradable materials with controlled functional properties for food uses, medical uses, packaging, agriculture, controlled release systems, etc. is discussed.

• 전자통신동향분석
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• 제32권2호
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• pp.29-36
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• 2017

본고에서는 바이오 기술(BT: Bio Technology)의 주요 소재인 DNA(DeoxyriboNucleic Acid, 디옥시리보핵산)를 정보기술(IT: Information Technology)과 나노 기술(NT: Nano Technology)에 적용한 세 가지 DNA 응용 기술 동향에 대해 소개하였다. 먼저 1958년 프랜시스 크릭(Francis Crick)이 주장한 센트럴 도그마(Central Dogma)의 출발점인 DNA의 구조와 기능에 대해 최대한 자세히 소개하였고, DNA의 염기 서열 방식을 이용한 DNA 저장장치에 관해 설명하였다. 그다음 장에서는 DNA의 자기 조립(Self-Assembly) 능력과 자기 복제 능력 및 다른 분자를 인식하여 결합하는 특성을 정보기술에 적용한 DNA 컴퓨터에 대해 설명하였다. 마지막으로, 나노 단위의 DNA 구조를 응용한 나노 기술 중에서 다양한 나노구조물을 만드는 기술인 DNA 오리가미 기술에 대해 설명하였다.

• 한국결정성장학회지
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• 제20권2호
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• pp.80-84
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• 2010

The temperature-programmed reduction of titanium oxide ($TiO_2$) with pure $CH_4$ was used for the preparation of titanium carbide crystallites. The synthesized materials had the different surface areas, indicating that the structural properties of these materials were strong functions of two different heating rates and space velocity employed. The titanium carbide crystallites were active for $NH_3$ decomposition. Since the reactivity varied with changes in the particle size, ammonia decomposition reactivity over the titanium carbides crystallites appeared to be related to the different active species. The reactivities of titanium carbide crystallites were two and three times lower than those of the vanadium and molybdenum carbide crystallites, respectively. These results suggested that the difference in activities might be related to the degree of electron transfer between metals and carbon.

• KSBB Journal
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• 제27권2호
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• pp.131-135
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• 2012

To develop potential cosmetic ingredients with antimicrobial and antioxidant activities of 4 Korean bamboo species (P. bambusoides, P. nigra var. henonis, P. pubescens and Sasa coreana) using three different extraction methods-water, ethanol and supercritical fluid extraction. Antimicrobial activities and DPPH assay have been examined. Among the antimicrobial activities against two test strains, Escherichia coli and Staphylococcus aureus, ethanol extracts of 3 bamboo trees, P. bambusoides, P. nigra var. henonis, and P. pubescens, showed stronger than those of supercritical extracts. However, 4 bamboo supercritical extracts showed dose-dependent increase in antioxidant activity by DPPH assay. These results suggest that water fraction of bamboo extracts may be useful for the cosmetic ingredient with low cytotoxicity.

• Transactions on Electrical and Electronic Materials
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• 제11권3호
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• pp.106-111
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• 2010

The convergence of significantly different and disparate technologies such as spintronics, carbon nano tube field effect transistors, photon and bio-responsive molecular switches, memristor and memristive systems and metamaterials, coupled with energy scavenging sources are gaining a renewed focus in the quest for new products. This paper will provide an insight into an anticipated technological revolution and will highlight a futuristic Roadmap to capture opportunities that are brought about as the results of formulation of new circuit components basically driven by emergence of nanoscale materials as part of System on System integration. Challenges as the result of new lumped components such as memristor, metamaterial-based lumped components and the like that will challenge the designers' comfort zone will also be discussed.