Biomolecular detection with a thin membrane transducer

Cha, Misun,Shin, Jaeha,Kim, June-Hyung,Kim, Ilchaek,Choi, Junbo,Lee, Nahum,Kim, Byung-Gee,Lee, Junghoon Royal Society of Chemistry 2008 Lab on a chip Vol.8 No.6

<P>We present a thin membrane transducer (TMT) that can detect nucleic acid based biomolecular reactions including DNA hybridization and protein recognition by aptamers. Specific molecular interactions on an extremely thin and flexible membrane surface cause the deflection of the membrane due to surface stress change which can be measured by a compact capacitive circuit. A gold-coated thin PDMS membrane assembled with metal patterned glass substrate is used to realize the capacitive detection. It is demonstrated that perfect match and mismatch hybridizations can be sharply discriminated with a 16-mer DNA oligonucleotide immobilized on the gold-coated surface. While the mismatched sample caused little capacitance change, the perfectly matched sample caused a well-defined capacitance decrease <I>vs.</I> time due to an upward deformation of the membrane by a compressive surface stress. Additionally, the TMT demonstrated the single nucleotide polymorphism (SNP) capabilities which enabled a detection of mismatching base pairs in the middle of the sequence. It is intriguing that the increase of capacitance, therefore a downward deflection due to tensile stress, was observed with the internal double mismatch hybridization. We further present the detection of thrombin protein through ligand-receptor type recognition with 15-mer thrombin aptamer as a receptor. Key aspects of this detection such as the effect of concentration variation are investigated. This capacitive thin membrane transducer presents a completely new approach for detecting biomolecular reactions with high sensitivity and specificity without molecular labelling and optical measurement.</P> <P>Graphic Abstract</P><P>A thin membrane transducer (TMT) capacitively detects deflections caused by chemomechanical recognition due to biomolecular reaction. The detection of DNA hybridization and protein binding with aptamers are demonstrated. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=b719101d'> </P>

Reversible metal-semiconductor transition of ssDNA-decorated single-walled carbon nanotubes.

Cha, Misun,Jung, Seungwon,Cha, Moon-Hyun,Kim, Gunn,Ihm, Jisoon,Lee, Junghoon American Chemical Society 2009 NANO LETTERS Vol.9 No.4

<P>A field effect transistor (FET) measurement of a single-walled carbon nanotube (SWNT) shows a transition from a metallic one to a p-type semiconductor after helical wrapping of DNA. Water is found to be critical to activate this metal-semiconductor transition in the ssDNA-SWNT hybrid. Raman spectroscopy confirms the same change in electrical behaviors. According to our ab initio calculations, a band gap can open up in a metallic SWNT with wrapped ssDNA in the presence of water molecules due to charge transfer.</P>

임베디드 S/W 재사용을 위한 모듈의 분류 및 설계 절차

유미선 ( Misun Yu ),차정은 ( Jung-eun Cha ),양영종 ( Yung-jong Yang ) 한국정보처리학회 2005 한국정보처리학회 학술대회논문집 Vol.12 No.2

임베디드 시스템이 점점 복잡해지고 다양해짐에 따라 이를 지원하는 임베디드 S/W 의 비중도 계속적으로 커지고 있으며 S/W 재사용에 대한 요구도 계속적으로 증가하고 있다. 그러나 유사한 기능을 지닌 S/W 에 대한 반복적인 수요가 증가함에도 불구하고, 재사용을 위한 체계적인 방법의 부재로 인하여 유사한 부분을 재사용 하지 못하고 있는 실정이다. 그러므로 체계적으로 재사용 S/W 모듈을 관리할 수 있는 지원 시스템과 모듈의 분류 방식, 그리고 재사용 지원 시스템을 이용하여 재사용 모듈을 실제 임베디드 S/W 개발에 적용할 수 있는 절차가 정의된다면 최종적으로 S/W 개발의 생산성을 향상 시킬 수 있을 것이다. 따라서 본 논문에서는 ETRI“임베디드 시스템 개발 프레임워크 구축”의 일환으로 구현되고 있는 재사용 지원 시스템을 위한 모듈의 형태 정의 및 형태와 크기에 따른 분류 방법, 재사용 모듈의 이용 절차에 대해 설명한다.

임베디드 S/W의 체계적 재사용을 위한 재사용 체계

유미선 ( Misun Yu ),차정은 ( Jung-eun Cha ),양영종 ( Yung-jong Yang ) 한국정보처리학회 2006 한국정보처리학회 학술대회논문집 Vol.13 No.1

다양한 환경 제약적인 특성들을 갖는 임베디드 소프트웨어를 공유 가능한 개별 단위의 재사용 자산으로 개발하고, 자산의 재사용을 활성화 시키기 위해서는 명확한 개발 절차, 기법, 도구 및 이들을 이용할 수 있게 하는 교육 등 통합적인 재사용 체계가 필요하다. 이를 위해 ETRI에서는 “임베디드 시스템 개발 프레임워크 구축”의 일환으로 임베디드 소프트웨어 개발 조직내의 체계적인 재사용을 위한 재사용 체계를 개발하였다. 재사용 체계는 문서나 코드의 실질적인 재사용 형태 및 절차를 정의하는 재사용 지침, 재사용 지침의 적용을 도와주는 도구인 재사용 지원 시스템, 그리고 재사용 지침과 재사용 지원 시스템을 조직에 보급하기 위한 방법인 재사용 체계 보급 정책으로 구성된다. 본 논문에서는 이러한 재사용 체계의 구성과 내용에 대해 설명한다.

Dissociation of Single-Strand DNA: Single-Walled Carbon Nanotube Hybrids by Watson−Crick Base-Pairing

Jung, Seungwon,Cha, Misun,Park, Jiyong,Jeong, Namjo,Kim, Gunn,Park, Changwon,Ihm, Jisoon,Lee, Junghoon American Chemical Society 2010 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.132 No.32

<P>It has been known that single-strand DNA wraps around a single-walled carbon nanotube (SWNT) by π-stacking. In this paper it is demonstrated that such DNA is dissociated from the SWNT by Watson−Crick base-pairing with a complementary sequence. Measurement of field effect transistor characteristics indicates a shift of the electrical properties as a result of this “unwrapping” event. We further confirm the suggested process through Raman spectroscopy and gel electrophoresis. Experimental results are verified in view of atomistic mechanisms with molecular dynamics simulations and binding energy analyses.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/2010/jacsat.2010.132.issue-32/ja102673m/production/images/medium/ja-2010-02673m_0005.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ja102673m'>ACS Electronic Supporting Info</A></P>

Charge Trap Flash structure with Feedback Field Effect Transistor for Processing in Memory

Junhyeong Lee,Misun Cha,Min-Woo Kwon 대한전자공학회 2023 Journal of semiconductor technology and science Vol.23 No.5

Recently, a memory wall has become a concern due to the increasing distance between memory and CPU in the von Neumann structure. While the CPU and logic devices operate quickly, their speed becomes irrelevant due to the slow data transfer between them. Consequently, addressing the data delay problem between the CPU and the logic elements is crucial. To tackle this issue, researchers have been exploring the Processing in Memory (PIM) technology, which enables simultaneous memory and computation. However, traditional volatile or nonvolatile memory-based PIM approaches have inherent limitations in overcoming the memory wall problem, as memory and computation are performed sequentially on separate devices. Therefore, there is a need to develop a new memory-logic device capable of performing read and operation simultaneously. In this paper, we propose a Feedback Field Effect Transistor (FBFET) with a charge trap layer that can fulfill both memory and computational roles, thus implementing an ideal Processing in Memory technology. The device features an oxide-nitride-oxide structure, where nitride is coupled to the oxide side of the FBFET. It accumulates electric charges in the floating body for memory operations and reads the data stored in the charge trap layer for logic operations. By selecting the control gate bias, the computing operation can be configured to perform AND or OR operations. This enables simultaneous memory and logical operations to take place.

Single-Crystal Apatite Nanowires Sheathed in Graphitic Shells: Synthesis, Characterization, and Application

Jeong, Namjo,Cha, Misun,Park, Yun Chang,Lee, Kyung Mee,Lee, Jae Hyup,Park, Byong Chon,Lee, Junghoon American Chemical Society 2013 ACS NANO Vol.7 No.7

<P>Vertically aligned one-dimensional hybrid structures, which are composed of apatite and graphitic structures, can be beneficial for orthopedic applications. However, they are difficult to generate using the current method. Here, we report the first synthesis of a single-crystal apatite nanowire encapsulated in graphitic shells by a one-step chemical vapor deposition. Incipient nucleation of apatite and its subsequent transformation to an oriented crystal are directed by derived gaseous phosphorine. Longitudinal growth of the oriented apatite crystal is achieved by a vapor–solid growth mechanism, whereas lateral growth is suppressed by the graphitic layers formed through arrangement of the derived aromatic hydrocarbon molecules. We show that this unusual combination of the apatite crystal and the graphitic shells can lead to an excellent osteogenic differentiation and bony fusion through a programmed smart behavior. For instance, the graphitic shells are degraded after the initial cell growth promoted by the graphitic nanostructures, and the cells continue proliferation on the bare apatite nanowires. Furthermore, a bending experiment indicates that such core–shell nanowires exhibited a superior bending stiffness compared to single-crystal apatite nanowires without graphitic shells. The results suggest a new strategy and direction for bone grafting materials with a highly controllable morphology and material conditions that can best stimulate bone cell differentiation and growth.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2013/ancac3.2013.7.issue-7/nn305767t/production/images/medium/nn-2012-05767t_0011.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn305767t'>ACS Electronic Supporting Info</A></P>

Inhibition of Apoptosis with Magnetic Nanoparticles and Static Magnetic Field

Jaeha Shin,Junghoon Lee,Misun Cha 대한기계학회 2012 대한기계학회 춘추학술대회 Vol.2012 No.3

ENERGY EFFICIENT GROWTH METHOD OF MICROALGAE USING THE BLUE LIGHT EMITTING DIODES

Hakgeun Jeong,Junghoon Lee,Misun Cha 한국신재생에너지학회 2011 AFORE Vol.2011 No.-

DNA-탄소나노튜브 복합체에서의 Watson-Crick 염기쌍 형성 연구

정승원(Seungwon Jung),차미선(Misun Cha),정남조(Namjo Jeong),이정훈(Junghoon Lee) 대한기계학회 2011 대한기계학회 춘추학술대회 Vol.2011 No.10

It has been known that a single strand DNA wraps around a SWNT by a π-π stacking. Here we demonstrate that such DNA is dissociated from the SWNT by forming a Watson-Crick base pairing with a complementary sequence. The measurement of FET characteristics indicates the shift of electrical property as a result of this “unwrapping” event. We further confirm the suggested process through atomic force microscopy, transmission electron microscopy, and gel electrophoresis.