• 제목/요약/키워드: micropatterning

검색결과 39건 처리시간 0.036초

Fabrication and Micropatterning of a Hybrid Composite of Amorphous Calcium Carbonate and Poly(ethylenimine)

  • Lee, Hyun-Sook;Ha, Tai-Hwan;Kim, Hyun-Min;Kim, Kwan
    • Bulletin of the Korean Chemical Society
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    • 제28권3호
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    • pp.457-462
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    • 2007
  • Amorphous calcium carbonate (ACC) can readily be prepared using ethanol as the reaction medium and ammonium carbonate as the source of carbon dioxide. Other additives, or any elaborate pH control are not needed to form the initial calcium carbonate precipitate. Ammonia generated from ammonium carbonate maintains the reaction medium in a neutral or weakly basic condition, retarding the crystallization of ACC, while ethanol itself inhibits the dissolution of ACC. The ACC prepared in this way provides a rare opportunity to fabricate molded biomimetic crystals in vitro, but the ACC is too fragile to be fabricated into proper shapes. The malleability of ACC is, however, greatly enhanced by incorporating poly(ethylenimine) (PEI). The ACC/PEI composite can then be fabricated, using a proper mold or template, into mechanically durable biomimetic crystals of definite shape. The ACC in the ACC/PEI composite can further be transformed into vaterite by heating under N2 atmosphere, while the native ACC simply converts into calcite.

펨토초 레이저 절삭 공정을 이용한 생분해성 나노섬유 표면 미세 패터닝 공정 (Micropatterning on Biodegradable Nanofiber Scaffolds by Femtosecond Laser Ablation Process)

  • 정용우;전인동;김유찬;석현광;정석;전호정
    • 한국표면공학회지
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    • 제49권6호
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    • pp.555-559
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    • 2016
  • A biodegradable nanofiber scaffolds using electrospining provide fibrous guidance cues for controlling cell fate that mimic the native extracellular matrix (ECM). It can create a pattern using conventional electrospining method, but has a difficulty to generate one or more pattern structures. Femtosecond(fs) laser ablation has much interested in patterning on biomaterials in order to distinguish the fundamental or systemic interaction between cell and material surface. The ablated materials with a short pulse duration using femtosecond laser that allows for precise removal of materials without transition of the inherent material properties. In this study, linear grooves and circular craters were fabricated on electrospun nanofiber scaffolds (poly-L-lactide(PLLA)) by femtosecond laser patterning processes. As parametric studies, pulse energy and beam spot size were varied to determine the effects of the laser pulse on groove size. We confirmed controlling pulse energy to $5{\mu}J-20{\mu}J$ and variation of lens maginfication of 2X, 5X, 10X, 20X created grooves of width to approximately $5{\mu}m-50{\mu}m$. Our results demonstrate that femtosecond laser processing is an effective means for flexibly structuring the surface of electrospun PLLA nanofibers.

미세접촉인쇄법을 이용한 지방세포 칩 제작 (Simple Fabrication of Adipocyte Cell Chip Using Micropatterning)

  • 김지용;정헌호;이창수;노창현
    • Korean Chemical Engineering Research
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    • 제54권2호
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    • pp.223-228
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    • 2016
  • 본 논문은 PDMS을 기반으로 한 미세접촉인쇄법을 사용하여 보다 효율적으로 지방세포를 선택적으로 배양접시에 부착시켰으며 패터닝 된 배양접시에서 지방세포가 빠르게 지방분화를 가능하게 하였다. PDMS을 이용한 선택적 표면 처리 방법은 기존의 세포칩 제작과 달리 소량의 유기용매사용, 저가의 장비 사용, 또한 효율적으로 특정 지역 안에서 지방세포를 고정화하고 성장시킬 수 있으며 이를 통해 지방세포의 생리학적 상태를 손쉽게 관찰할 수 있는 분석 기술로 활용된다. 이렇게 구성된 지방세포칩 위에 대표적인 비만 억제제 약물인 Orlistat을 $0.2{\mu}M{\sim}5.0{\mu}M$ 농도로 처리하였을 때 대조군에 비하여 최대 26.5%의 억제 효과가 나타남을 확인하였다. 따라서, 본 논문에서 제안하는 방법을 통하여 다양한 비만 억제제 약물 탐색을 위한 세포칩으로 활용이 가능할 것으로 기대된다.

국부증착용 마이크로 샤도우 마스크 제작 (Fabrication of Miniaturized Shadow-mask for Local Deposition)

  • 김규만;유르겐부르거
    • 한국정밀공학회지
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    • 제21권8호
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    • pp.152-156
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    • 2004
  • A new tool of surface patterning technique for general purpose lithography was developed based on shadow mask method. This paper describes the fabrication of a new type of miniaturized shadow mask. The shadow mask is fabricated by photolithography and etching of 100-mm full wafer. The fabricated shadow mask has over 388 membranes with apertures of micrometer length scale ranging from 1${\mu}{\textrm}{m}$ to 100s ${\mu}{\textrm}{m}$ made on each 2mm${\times}$2mm large low stress silicon nitride membrane. It allows micro scale patterns to be directly deposited on substrate surface through apertures of the membrane. This shadow mask method has much wider choice of deposit materials, and can be applied to wider class of surfaces including chemical functional layer, MEMS/NEMS surfaces, and biosensors.

뉴런온칩 기술: 미세전극칩시스템과 신경세포 패터닝 기술 (Neuron-on-a-Chip technology: Microelectrode Array System and Neuronal Patterning)

  • 남윤기
    • 대한의용생체공학회:의공학회지
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    • 제30권2호
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    • pp.103-112
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    • 2009
  • Neuron-on-a-Chip technology is based on advanced neuronal culture technique, surface micropatterning, microelectrode array technology, and multi-dimensional data analysis techniques. The combination of these techniques allowed us to design and analyze live biological neural networks in vitro using real neurons. In this review article, two underlying technologies are reviewed: Microelectrode array technology and Neuronal patterning technology. There are new opportunities in the fusion of these technologies to apply them in neurobiology, neuroscience, neural prostheses, and cell-based biosensor areas.