• 제목/요약/키워드: Surface functionalization

검색결과 127건 처리시간 0.026초

부분적 기능화된 다이아몬드를 이용한 single mismatched DNA 검출 특성 (Characterization of partially functionalized diamond for detecting single mismatched DNA)

  • 양정훈;송광섭
    • 한국기계가공학회지
    • /
    • 제12권4호
    • /
    • pp.29-33
    • /
    • 2013
  • Here we report a partially aminated micropattern via direct functionalization and examine eleven different solution-phase probe DNAs hybridizing with the same target DNA on both hydrogen and oxygen terminated diamond. The hybridization intensities determined by epifluorescence microscopy were compared and are influenced strongly by the negatively charged surface and mismatched position of its sequence with immobilized probe DNA.

The Influence of Functionalization of the Fe3O4 Nanoparticle on its Dispersion Property

  • Han, Jin Soon;An, Gye Seok;Park, Bong Geun;Choi, Sung-Churl
    • 한국세라믹학회지
    • /
    • 제55권1호
    • /
    • pp.80-84
    • /
    • 2018
  • In this study, to improve the dispersity of $Fe_3O_4$ nanoparticles, dispersion properties were considered with various types of functionalization of $Fe_3O_4$ nanoparticles. Due to its high surface area, the electrically neutral state of its surfaces, and its magnetic momentum, $Fe_3O_4$ nanoparticles are easily aggregated in solution. In order to prevent aggregation, $Fe_3O_4$ nanoparticles were functionalized with carboxyl and amine groups in the form of a polymer compound. Carboxyl and amine groups were attached to the surface of $Fe_3O_4$ nanoparticles and the absolute value of the zeta potential was found to be enhanced by nearly 40 eV. Furthermore, the morphology and the magnetic property were analyzed for the application of $Fe_3O_4$ nanoparticles as a magnetic fluid.

Preparation of Modified Hollow Polypropylene Membrane and Their Adsorption Properties of ${\gamma}$-Globulins

  • Hwang, Taek-Sung;Park, Jin-Won
    • Macromolecular Research
    • /
    • 제11권5호
    • /
    • pp.347-351
    • /
    • 2003
  • The hydrophobic ligand-containing hollow polypropylene (PP) membranes were synthesized by the mutual radiation induced graft copolymerization with glycidylmethacrylate (GMA) onto hollow PP membrane followed by the subsequent functionalization with L-phenylalanine. FT-IR, elemental analysis and UV spectroscopy were utilized to characterize copolymer composition, and degree of grafting, functionalization conversion and ${\gamma}$-globulins adsorption. The degree of grafting on the PP surface increased with the reaction time and total dose of E-beam. In the subsquent functionalization, the amount of L-phenylalanine increased with the increase in the degree of grafting and the degree of conversion was about 30%. The ${\gamma}$-globulins adsorption experiments showed that adsorption capacity had a maximum value at pH 8. The ${\gamma}$-globulins adsorption capacity in the basic pH region was higher than in the acidic pH region.

실리카의 이온성 액체 기능화가 메탈로센 담지촉매의 에틸렌 중합 거동에 미치는 영향 (Influence of Functionalization of Silica with Ionic Liquid on Ethylene Polymerization Behavior of Supported Metallocene)

  • 이정숙;이창일;고영수
    • 공업화학
    • /
    • 제27권1호
    • /
    • pp.86-91
    • /
    • 2016
  • Ionic liquid 기능화 및 메탈로센 촉매 담지를 위해 세 종류의 무정형 실리카와 SBA-15를 담체로 사용하였다. Ionic liquid가 표면 기능화된 실리카는 1,3-bis(cyanomethyl)imidazolium chloride의 염소 음이온과 실리카 표면의 OH 그룹 사이의 상호작용에 의해 합성되었다. 에틸렌 중합을 위해 ionic liquid가 기능화된 실리카에 메탈로센과 조촉매 methylaluminoxane(MAO)을 담지하였다. SBA-15와 비교하여 큰 기공 크기를 갖는 ionic liquid가 표면 기능화된 XPO-2412와 XPO-2410에 담지된 촉매는 기능화되지 않은 실리카에 담지된 촉매보다 높은 활성을 보였다. 그러나 SBA-15에 담지된 촉매는 ionic liquid의 표면 기능화 후에 활성이 감소하였다. 이는 ionic liquid와 메탈로센 촉매, 조촉매 MAO가 담지되면 기공의 크기가 크게 줄어들기 때문에 중합 시 에틸렌 모노머와 조촉매가 기공 내 촉매 활성점으로 확산하는데 제한을 받기 때문이다. 또한 실리카 표면의 OH 그룹의 농도 변화에 따른 촉매의 중합 활성에 대한 영향을 연구하였다. 무정형 실리카의 OH 그룹의 농도가 증가할수록 중합 활성도 증가하였으며 실리카에 담지된 촉매의 중합 활성은 ionic liquid 표면처리 후에도 유사한 경향을 보였다.

Bioconjugation of Poly(poly(ethylene glycol) methacrylate)-Coated Iron Oxide Magnetic Nanoparticles for Magnetic Capture of Target Proteins

  • Kang, Sung-Min;Choi, In-Sung S.;Lee, Kyung-Bok;Kim, Yong-Seong
    • Macromolecular Research
    • /
    • 제17권4호
    • /
    • pp.259-264
    • /
    • 2009
  • Chemical modification of magnetic nanoparticles(MNPs) with functional polymers has recently gained a great deal of attention because of the potential application of MNPs to in vivo and in vitro biotechnology. The potential use of MNPs as capturing agents and sensitive biosensors has been intensively investigated because MNPs exhibit good separation-capability and binding-specificity for biomolecules after suitable surface functionalization processes. In this work, we demonstrate an efficient method for the surface modification of MNPs, by combining surface-initiated polymerization and the subsequent conjugation of the biologically active molecules. The polymeric shells of non-biofouling poly(poly(ethylene glycol) methacrylate)(pPEGMA) were introduced onto the surface of MNPs by surface-initiated, atom transfer radical polymerization(SI-ATRP). With biotin as a model of biologically active compounds, the polymeric shells underwent successful post-functionalization via activation of the polymeric shells and bioconjugation of biotin. The resulting MNP hybrids showed a biospecific binding property for streptavidin and could be separated by magnet capture.

Non-Functionalized Water Soluble Carbon Nanotubes

  • ;최정일;임연민;김유나;김창준;강상수;남태현;강동우
    • 한국재료학회:학술대회논문집
    • /
    • 한국재료학회 2010년도 춘계학술발표대회
    • /
    • pp.43.2-43.2
    • /
    • 2010
  • Most of previous methods for the dispersions of carbon nanotube were achieved by various chemical functionalizations. In this study, however, we generated highly water dispersed carbon nanofibers by altering intrinsic materials property only, such as crystallinity of outer layers of carbons, without chemical treatment. Although most of chemical functionalization requires acidic treatment and may degrade their chemical functions by interacting with other molecules, suggested strategy demonstrated a simple but chemically non-degradable carbon nanotube for the application of various medical applications, such as drug delivery system and implant coatings.Furthermore, protein adsorption was increased by the reducing surface crystalinity since outer activated surface induced more adsorption of oxygen and eventually greater protein adsorption than pristine carbon nanofibers.

  • PDF

Band Structure Engineering of Monolayer MoS2 by Surface Ligand Functionalization

  • Lee, Sang Yoon;Ramzan, Sufyan
    • EDISON SW 활용 경진대회 논문집
    • /
    • 제4회(2015년)
    • /
    • pp.367-370
    • /
    • 2015
  • Monolayer transition metal dicalcogenide (TMDC) materials are currently attracting extensive attention due to their distinctive electronic, transport, and optical properties. For example, monolayer $MoS_2$ exhibits a direct band gap in the visible frequency range, which makes it an attractive candidate for the photocatalytic water splitting. For the photoelectrochemical water splitting, the appropriate band edge positions that overlap with the water redox potential are necessary. Similarly, appropriate band level alignments will be crucial for the light emitting diode and photovoltaic applications utlizing heterojunctions between two TMDC materials. Carrying out first-principles calculations, we here investigate how the band edges of $MoS_2$ can be adjusted by surface ligand functionalization. This study will provide useful information for the realization of ligand-based band engineering of monolayer $MoS_2$ for various electronic, energy, and bio device applications.

  • PDF