The authors would like to acknowledge the support from the Department of Earth Sciences, Uppsala University for supporting part of this research.

다중 벽 탄소 나노 튜브의 1 기능화 <ol><li> 안전 안경, 장갑 및 실험실 코트를 사용하여, 흄 후드 내부의 전체 작용 단계를 수행합니다. 눈금 실린더를 사용하여 질산 산성 황산 24 ㎖를 8 mL로 측정 한 다음 비이커로 옮긴다. 분석 저울에 주석 호일 컨테이너를 사용하여 비커에 처리되지 않은 다중 벽 탄소 나노 튜브의 32 mg을 추가 (최종 농도는 1 ㎎ / 산 혼합물의 ml를해야한다). </li><li> 첫째, 실온에서 2 시간 동안 초음파 세척기 (목욕)에 MWCNT 산 혼합물 비커를 유지. 그런 다음, 열 및 90에서 5 시간 동안 MWCNT-산 용액을 저어 핫 플레이트를 사용하여 ° C. </li><li> 필터 홀더에 배치 0.2 μm의 세공 직경의 PTFE 멤브레인 필터로 CNT 현탁액을 여과하고 여과를 돕기 위해 진공을 사용한다. 부분에 의해 여과 부분을 수행하고 여러 필터 멤브레인 (하나의 필터에 대한 부분마다 상기 혼합물의 약 1/4 일)를 사용합니다. 끓는 물에 추가혼합물의 pH가 5보다 커질 때까지 여과 공정시에 산 용액을 걸러. </li><li> 이 꺼져 있고 진공 시스템에 아무것도를 소개하지 전에 항상를 주입합니다. 폐액 수집 비커를 사용한다. </li><li> 폐기물 용기에 붓고 여과 산 (폐기물 처리 시설로 폐기물 용기를 보내거나 수돗물 중 적어도 열 배를 가산함으로써 싱크로 덤핑 전에 액체 희석). </li><li> CNT (약 24 시간 건조를 완료하기 위해 음식을 증발로 유지 다중 벽 탄소 나노 튜브와 여과막을 전송하고, 데시 케이 터에 넣어 요리 (실리카겔 약 100g 함유) 및 진공 환경을 생성 (약 1 시간 동안 진공을두고) ). <ol><li> 주걱을 사용하여 조심스럽게 막에서 탄소 나노 튜브를 긁어 깨끗한 용기 내로 입자를 옮긴다. 다중 벽 탄소 나노 튜브 분말의 무게를 측정하고 향후 사용을 위해 컨테이너를 레이블을 붙입니다. </li></ol></li></ol> 2. Poro전송 실험에 대한 우리 미디어 <ol><li> 실리카 모래의 산 세척 0.1 M HCl 용액을 준비합니다. <ol><li> 안전 안경, 장갑, 실험실 코트와 흄 후드 내부의 모든 단계를 수행합니다. 2 L 플라스크에 1 L를 탈 이온수를 추가합니다. 눈금 실린더를 사용하여 37 % 염산 8 mL로 측정한다. </li><li> 조심스럽게 탈 이온수에 염산을 추가합니다. 혼합하기 위해 조심스럽게 플라스크를 흔들어. </li></ol></li><li> 준비된 HCl 용액으로 모래를 씻으십시오. <ol><li> 약 1,000g 모래의 무게를. HCl 용액과 플라스크에 모래의 1/3를 추가하고 모래 (모래마다의 1/3)의 나머지 부분을 추가 한 후 혼합하기 위해 두 번 플라스크를 흔들어. </li><li> 플라스크를 세 번 흔들어 30 분간 모래 산을 둡니다. </li><li> 적어도 8 배를 산 폐액 용기 플라스크에서 액체를 붓고 탈 이온수로 모래를 씻어. </li></ol></li><li> H 2 O 2 용액으로 모래를 씻으십시오. <ol><li> 에 탈 이온수 700 ml에 추가모래 플라스크는 눈금 실린더를 사용하여 2 O 2 30 % 용액 40㎖의 H를 측정한다. </li><li> 모래 플라스크에 H 2 O 2 솔루션을 추가하고 혼합하기 위해 두 번 흔들어. 플라스크에 160 ml의 H 2 O 2 총이 때까지 2 O 2 용액을 3 회 30 % H의 또 다른 (40)를 가하여. </li><li> 흔들어 용액과 모래 매번 혼합하고, 반응이 완료 될 수 있도록 40 ​​분 동안 모래 H 2 O 2 용액을 떠난다. 플라스크를 흔들어 플라스틱 막대 매 10 분에 모래를 저어. </li><li> 싱크대 아래로 액체를 가만히 따르다 30 초 동안 수돗물을 실행합니다. </li></ol></li><li> 씻어 모래를 건조. <ol><li> 탈 이온수와 모래를 씻어 최소 8 시간은 모든 솔루션 제거 또는 반응 생성물을 통해 버려지합니다. 흔들어 세척 할 때 철저하게 약동하십시오. </li><li> 건조 24 시간 동안 오븐 (105 ° C)로 세척 모래 플라스크에 넣고, 다음 사용하여 오븐에서 모래를 취할모래가 식을 때까지 오븐 벙어리 장갑 2 시간 동안 카운터에 둡니다. </li><li> 플라스틱 용기에 깨끗한 모래를 전송합니다. 컨테이너를 표시하고 사용하기위한 준비를 적절한 선반에 배치합니다. </li></ol></li></ol> 3. 열 실험 <ol><li> 배경 용액의 조제. <ol><li> 열 실험에 적합한 배경 솔루션 화학을 준비합니다. </li><li> 다음 실험에 적합한 이온 강도를 달성하기 위해 pH 및 염화나트륨 염을 조정할 0.1 M HCl 및 0.1 M의 NaOH 용액을 사용한다. </li></ol></li><li> 열 선택. <ol><li> 이 실험 (5 및 이온 강도 : 본 연구에서 2 mM의 산도) 2.5 cm 직경 15cm 길이의 유리 열을 선택합니다. 유리관의 양쪽에있는 스틸 메쉬 필터 (0.2 mm)를 사용합니다. </li><li> 컬럼에 연결된 튜브 플러시 및 액체 흐름의 유형을 제어하기 위해 3- 방향 밸브까지 배경 용액으로 기입 (또는 다중 벽 탄소 나노 튜브 용액 (다중 벽 탄소 나노 튜브의 solution 또는 배경 용액)도 1에 도시 된 바와 같이. </li></ol></li><li> 컬럼의 습식 포장. <ol><li> 규모에 깨끗한 모래의 무게를 측정하고 선택한 열 크기 깨끗한 모래 124g을. </li><li> 높은 정밀도 연동 펌프를 사용합니다. 액체 유동의 2 ml / 분을 달성하기 펌프를 보정. </li><li> 수위가 증류탑의 저부 위의 몇 센티미터 때까지 아래로부터 열을 채우기 위해 펌프를 켜고. 열에 한번에 측정 모래의 약 1/10을 넣어하지만 모래 레벨이 열에있는 수위 위에 오지 않는지 확인. 모래 수준 이상으로 유지하기 위해 계속 열로 물 흐름을 계속합니다. </li><li> 완전 충전 후 적절한 필터 메쉬 열 뚜껑을 닫습니다. </li><li> 충전 탑은 적어도 1 시간 동안 흐르게. 칼럼의 개개의 파라미터는 다음 표 1에 나타내었다. </li></ol></li><li> 트레이서 시험. <ol><li> 에스MWCNT 솔루션 실험 이전에 추적 테스트와 열 실험을 타트. </li><li> 실험을 시작하기 위해 (20 ㎎ / L로 음식 색 트레이서를 사용하여) 트레이서 용액에 3 방향 전환 밸브. </li><li> 매 2 분에서 컬럼으로부터 유출을 채취 (즉, 4 ㎖ / 각 샘플링 튜브 내의 샘플)도 1에 도시 된 바와 같이 연결된 분획 수집기를 사용. </li><li> 4.32 세공 용적에 대한 트레이서 용액을 주입 계속 또한 실험의 위상을 I라고 (즉, 용액 모래 충전 탑의 총 세공 빈 공간을 통과 4.32 배). </li><li> 다른 기공 부피 4.32 대 (트레이서 실험의 경우 DI 물) 배경 용액 흐르도록 3 방향 전환 밸브. </li></ol></li><li> 다중 벽 탄소 나노 튜브 용액의 조제. <ol><li> 원하는 solutio로 (수용액 200 ㎖을 함유하는 300 ml의 비이커에 기능화 된 다중 벽 탄소 나노 튜브 15mg의 배치하여 분산, 기능화 된 다중 벽 탄소 나노 튜브 용액을 만들기N 화학 즉, pH가 5 및 2 mM의 이온 전류 실험 조건에서의 강도)과 15 분 동안 40 %의 출력되는 동력을 비커에 넣고 초음파 프로브를 호 모지 나이저 (사용). 15 ㎎ / L의 농도를 달성 MWCNT 동일한 수용액 800 mL를 다른 다중 벽 탄소 나노 튜브 분산 용액을 섞는다. </li><li> 크기와 후 기능화 된 나노 입자의 형상에 대한 스톡 용액의 주사 전자 현미경 (SEM) 이미지 분석을 수행한다. </li></ol></li><li> MWCNT 전송 실험. <ol><li> 열 실험을 시작 MWCNT 용액에 3 방향 전환 밸브. </li><li> 연결된 부분 수집기를 사용하여 매 2 분의 열에서 유출 샘플을 수집합니다. </li><li> 4.32 기공 부피 대 용액 MWCNT (I 실험의 위상)을 주입한다. </li><li> 실험의 단계 II라고 다른 세공 용적 4.32, 배경 용액을 흐르게 3 방향 전환 밸브. </li><li> backgro에의 주입 관 변경상기 실험의 위상 III라고 다른 4.32 세공 용적에 대한 흐름을 계속 (튜브에서 공기의 입구를 피하기 위해 잠시 동안 펌프를 정지 한 후) DI 물 병으로 싶게 용액. </li></ol></li><li> 샘플 분석. <ol><li> 튜브 랙에 분수 집에서 모든 튜브 샘플을 전송합니다. </li><li> , 시료 분석, 즉를위한 UV / VIS 분광 광도계를 준비 수집 된 시료의 정량에 대한 적절한 검사 파장을 찾을 수 있습니다. MWCNT 솔루션 및 추적 솔루션을위한 333 nm 파장 400 nm의를 사용합니다. </li><li> I, II, 및 (이전 단계에서 더 적합하다고 판단하는 경우 또는 상이한 파장) 400 nm의 파장을 사용하는 큐벳 III 및 데이터를 저장하는 단계 동안 컬럼으로부터 수집 된 모든 샘플을 스캔. </li><li> 분광 광도계로부터 데이터를 수집하고 대표적인 결과에 나타낸 바와 같이 (예를 들면, 파과 곡선을 얻기 위해 시간 또는 세공 용적 대 그리면,도3). </li><li> 제타 사이 저를 이용하여 유입 및 유출 샘플의 크기 분석 (수력 학적 직경)을 수행하고, 주사 전자 현미경을 사용하여 두 유출입 샘플에 대한 연구를 수행 시각화. </li></ol></li></ol>

<ol><li>Maynard, A. D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Safe+handling+of+nanotechnology%5BTitle%5D)+AND+%22Nature%22%5BJournal%5D)">Safe handling of nanotechnology.</a> Nature. 444, 267-269 (2006).</li>
<li>Mauter, M., Elimelech, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Environmental+applications+of+carbon-based+nanomaterials%5BTitle%5D)+AND+%22Environ.+Sci.+Technol%22%5BJournal%5D)">Environmental applications of carbon-based nanomaterials.</a> Environ. Sci. Technol. 42 (16), 5843-5859 (2008).</li>
<li>Darka-Kagy, K., Khodadoust, A. P., Reddy, K. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Reactivity+of+aluminum+lactate-modified+nanoscale+iron+particles+with+pentachlorophenol+in+soils%5BTitle%5D)+AND+%22Environ.+Eng.+Sci%22%5BJournal%5D)">Reactivity of aluminum lactate-modified nanoscale iron particles with pentachlorophenol in soils.</a> Environ. Eng. Sci. 27 (10), 861-869 (2010).</li>
<li>Lin, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Fate+and+transport+of+engineered+nanomaterials+in+the+environment%5BTitle%5D)+AND+%22J.+Environ.+Qual%22%5BJournal%5D)">Fate and transport of engineered nanomaterials in the environment.</a> J. Environ. Qual. 39 (6), 1896-1908 (2010).</li>
<li>Petersen, E. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Potential+release+pathways%2C+environmental+fate%2C+and+ecological+risks+of+carbon+nanotubes%5BTitle%5D)+AND+%22Environ.+Sci.+Technol%22%5BJournal%5D)">Potential release pathways, environmental fate, and ecological risks of carbon nanotubes.</a> Environ. Sci. Technol. 45 (23), 9837-9856 (2011).</li>
<li>Wiesner, M., Bottero, J. Y. <a target="_blank" href="http://scholar.google.com/scholar?hl=en&safe=off&q=author%3aWiesner%2C+M+%22Environmental+nanotechnology%22">Environmental nanotechnology</a>. , McGraw-Hill Companies. The Blacklick, OH. (2007).</li>
<li>Klaine, S. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Nanomaterials+in+the+environment%3A+Behavior%2C+fate%2C+bioavailability%2C+and+effects%5BTitle%5D)+AND+%22Environ.+Toxicol.+Chem%22%5BJournal%5D)">Nanomaterials in the environment: Behavior, fate, bioavailability, and effects.</a> Environ. Toxicol. Chem. 27 (9), 1825-1851 (2008).</li>
<li>Wang, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Toxicity+effects+of+four+typical+nanomaterials+on+the+growth+of+Escherichia+coli%2C+Bacillus+subtilis+and+Agrobacterium+tumefaciens%5BTitle%5D)+AND+%22Environ.+Earth+Sci%22%5BJournal%5D)">Toxicity effects of four typical nanomaterials on the growth of Escherichia coli, Bacillus subtilis and Agrobacterium tumefaciens.</a> Environ. Earth Sci. 65 (6), 1643-1649 (2012).</li>
<li>Shen, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Polyethyleneimine+mediated+functionalization+of+multi-walled+carbon+nanotubes%3A+Synthesis+characterization%2C+and+in+vitro+toxicity+assay%5BTitle%5D)+AND+%22J.+Phys.+Chem.+C%22%5BJournal%5D)">Polyethyleneimine mediated functionalization of multi-walled carbon nanotubes: Synthesis characterization, and in vitro toxicity assay.</a> J. Phys. Chem. C. 113 (8), 3718-3724 (2009).</li>
<li>Sahithi, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Polymeric+conposites+containing+carbon+nanotubes+for+bone+tissue+engineering%5BTitle%5D)+AND+%22Int.+J.+Biol.+Marcomol%22%5BJournal%5D)">Polymeric conposites containing carbon nanotubes for bone tissue engineering.</a> Int. J. Biol. Marcomol. 46 (3), 281-283 (2010).</li>
<li>Petersen, E., Huang, Q., Weber, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Bioaccumulation+of+radio-labeled+carbon+nanotubes+by+Eisnia+Foetida%5BTitle%5D)+AND+%22Environ.+Sci.+Technol%22%5BJournal%5D)">Bioaccumulation of radio-labeled carbon nanotubes by Eisnia Foetida.</a> Environ. Sci. Technol. 42 (8), 3718-3724 (2008).</li>
<li>Gottschalk, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Modeled+Enrionmental+concentrations+of+engineered+nanomaterials+for+different+regions%5BTitle%5D)+AND+%22Enrviron.+Sci.+Technol%22%5BJournal%5D)">Modeled Enrionmental concentrations of engineered nanomaterials for different regions.</a> Enrviron. Sci. Technol. 43 (24), 9216-9222 (2009).</li>
<li>Liu, X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((et+al.Mobility+of+multiwalled+carbon+nanotubes+in+porous+media.Environ%5BTitle%5D)+AND+%22Sci.+Technol%22%5BJournal%5D)">et al.Mobility of multiwalled carbon nanotubes in porous media.Environ.</a> Sci. Technol. 43 (21), 8153-8158 (2009).</li>
<li>Tian, Y., Gao, B., Ziegler, K. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((High+mobility+of+SDBS-dispersed+single-walled+carbon+nanotubes+in+saturated+and+unsaturated+porous%5BTitle%5D)+AND+%22J.+Hazard.+Mater%22%5BJournal%5D)">High mobility of SDBS-dispersed single-walled carbon nanotubes in saturated and unsaturated porous.</a> J. Hazard. Mater. 186 (2-3), 1766-1772 (2011).</li>
<li>Mattison, N. T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Impact+of+porous+media+grain+size+on+the+transport+of+multi-walled+carbon+nanotubes%5BTitle%5D)+AND+%22Environ.+Sci.+Technol%22%5BJournal%5D)">Impact of porous media grain size on the transport of multi-walled carbon nanotubes.</a> Environ. Sci. Technol. 45 (22), 9765-9775 (2011).</li>
<li>Kasel, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Limited+transport+of+functionlized+multi-walled+carbon+nanotubes+in+two+natural+soils%5BTitle%5D)+AND+%22Environ.+Pollution%22%5BJournal%5D)">Limited transport of functionlized multi-walled carbon nanotubes in two natural soils.</a> Environ. Pollution. 180, 152-158 (2013).</li>
<li>Yu, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Effects+of+humic+acid+and+Tween-80+on+behavior+of+decabromodiphenyl+ether+in+soil+columns%5BTitle%5D)+AND+%22Environ.+Earth+Sci%22%5BJournal%5D)">Effects of humic acid and Tween-80 on behavior of decabromodiphenyl ether in soil columns.</a> Environ. Earth Sci. 69 (5), 1523-1528 (2013).</li>
<li>Jaisi, D. P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Transport+of+single-walled+carbon+nanotubes+in+porous+media%3A+filtration+mechanisms+and+reversibility%5BTitle%5D)+AND+%22Environ.+Sci.+Technol%22%5BJournal%5D)">Transport of single-walled carbon nanotubes in porous media: filtration mechanisms and reversibility.</a> Environ. Sci. Technol. 42 (22), 8317-8323 (2008).</li>
<li>Tiraferri, A., Tosco, T., Sethi, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Transport+and+retention+of+microparticles+in+packed+sand+columns+at+low+and+intermediate+ionic+strengths%3A+experiments+and+mathematical+modeling%5BTitle%5D)+AND+%22Environ.+Earth+Sci%22%5BJournal%5D)">Transport and retention of microparticles in packed sand columns at low and intermediate ionic strengths: experiments and mathematical modeling.</a> Environ. Earth Sci. 63 (4), 847-859 (2011).</li>
<li>Tian, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Deposition+and+transport+of+functionalized+carbon+nanotubes+in+water-saturated+sand+columns%5BTitle%5D)+AND+%22J.+Hazard.+Mater%22%5BJournal%5D)">Deposition and transport of functionalized carbon nanotubes in water-saturated sand columns.</a> J. Hazard. Mater. 213-214, 265-272 (2012).</li>
<li>Mekonen, A., Sharma, P., Fagerlund, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Transport+and+mobilization+of+multiwall+carbon+nanotubes+in+quartz+sand+under+varying+saturation%5BTitle%5D)+AND+%22Environ.+Earth+Sci%22%5BJournal%5D)">Transport and mobilization of multiwall carbon nanotubes in quartz sand under varying saturation.</a> Environ. Earth Sci. 71 (8), 3751-3760 (2014).</li>
<li>Sharma, P., Bao, D., Fagerlund, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Deposition+and+mobilization+of+functionalized+multiwall+carbon+nanotubes+in+saturated+porous+media%3A+effect+of+grain+size%2C+flow+velocity+and+solution+chemistry%5BTitle%5D)+AND+%22Environ.+Earth+Sci%22%5BJournal%5D)">Deposition and mobilization of functionalized multiwall carbon nanotubes in saturated porous media: effect of grain size, flow velocity and solution chemistry.</a> Environ. Earth Sci. , (2014).</li>
<li>Phenrat, T., Lowry, G. V., Hotze, E. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Nanoparticle+aggregation%3A+challenges+to+understanding+transport+and+reactivity+in+the+environment%5BTitle%5D)+AND+%22J.+Environ.+Qual%22%5BJournal%5D)">Nanoparticle aggregation: challenges to understanding transport and reactivity in the environment.</a> J. Environ. Qual. 39 (6), 1909-1924 (2010).</li>
<li>Crist, J. T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Transport+and+retention+mechanisms+of+colloids+in+partially+saturated+porous+media%5BTitle%5D)+AND+%22Vadose+Zone+J%22%5BJournal%5D)">Transport and retention mechanisms of colloids in partially saturated porous media.</a> Vadose Zone J. 4 (1), 184-195 (2005).</li>
<li>Jaisi, D. P., Elimelech, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Single-walled+carbon+nanotubes+exhibit+limited+transport+in+soil+columns%5BTitle%5D)+AND+%22Environ.+Sci.+Technol%22%5BJournal%5D)">Single-walled carbon nanotubes exhibit limited transport in soil columns.</a> Environ. Sci. Technol. 43 (24), 9161-9166 (2009).</li>
<li>Corapcioglu, M. Y., Choi, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Modeling+colloid+transport+in+unsaturated+porous+media+and+validation+with+laboratory+column+data%5BTitle%5D)+AND+%22Water+Resour.+Res%22%5BJournal%5D)">Modeling colloid transport in unsaturated porous media and validation with laboratory column data.</a> Water Resour. Res. 32 (12), 3437-3449 (1996).</li>
<li>Wan, J., Wilson, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Colloid+transport+in+unsaturated+porous+media%5BTitle%5D)+AND+%22Water+Resour.+Res%22%5BJournal%5D)">Colloid transport in unsaturated porous media.</a> Water Resour. Res. 30 (4), 857-864 (1994).</li>
<li>Wan, J., Wilson, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Visualization+of+the+role+of+the+gas-water+interface+on+the+fate+and+transport+of+colloids+in+porous+media%5BTitle%5D)+AND+%22Water+Resour.+Res%22%5BJournal%5D)">Visualization of the role of the gas-water interface on the fate and transport of colloids in porous media.</a> Water Resour. Res. 30 (1), 11-24 (1994).</li>
<li>Bradford, S. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Physical+factors+affecting+the+transport+and+fate+of+colloids+in+saturated+porous+media%5BTitle%5D)+AND+%22Water+Resour.+Res%22%5BJournal%5D)">Physical factors affecting the transport and fate of colloids in saturated porous media.</a> Water Resour. Res. 38 (12), (2002).</li>
<li>Bradford, S. A., Torkzaban, S., Walker, S. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Coupling+of+physical+and+chemical+mechanisms+of+colloid+straining+in+saturated+porous+media%5BTitle%5D)+AND+%22Water+Res%22%5BJournal%5D)">Coupling of physical and chemical mechanisms of colloid straining in saturated porous media.</a> Water Res. 41 (13), 3012-3024 (2007).</li>
</ol>

The authors declare that they have no competing financial interests.

다중 벽 탄소 나노 튜브 기능화의 효과 도 2는 작용 화 된 다중 벽 탄소 나노 튜브의 안정성이 확인 된 바와 같이, MWCNT의 용출 부피에서 관측 된 차이는 다중 벽 탄소 나노 튜브의 표면 (-COOH) 그룹에 의한 작용 및 카르복실기의 첨가 특히 때문이었다 (도 3 및도 4). 유사한 작용 화 공정에서 산소의 존재는 X 선 광전자 분광법에 의해 확인 하...

정보 기술, 에너지, 환경 과학, 의학, 국토 안보, 식품 안전 및 수송 등의 산업 분야에서 많은 기술을 개선하기 위해 다양한 종류의 나노 입자를 사용하는 나노 기술의 최근 발전과 함께; 토양 및 지하수의 나노 입자의 수송 및 유지에 대한 철저한 이해를 위해 평가뿐만 아니라 나노 입자 설계 1-3의 환경 응용에 중요하다. 탄소 나노 튜브는 대부분의 제조 된 탄소 계 나노 입자 2,4- 중 하나이다. 탄소 나노 튜브는 일반적으로 100 나노 미터 이하의 직경이 50 ㎛ 인 100 nm 범위의 길이를 갖는 그라 펜 길고 원통형이다. 그들은 전자, 광학, 화장품, 생물 의학 기술 (예를 들어, 복합 재료) (5)와 같은 많은 응용 프로그램에서 사용을 가속화 독특한 특성을 보유하고 있습니다. 사용 증가로, 또한 증가 R이인체 노출 및 효과 건강에뿐만 아니라 CNT 및 환경 5-8 다른 탄소 기반 나노 물질 처리 다음과 생태계에 부정적인 영향을 ISK. 지표면 변형 (비관 능화 된)로, 탄소 나노 튜브는 매우 소수성이며 수용액에 응집하는 경향이있다. 기능화 된 탄소 나노 튜브는, 그러나, 분산 수용액에서 안정하고 이러한 약물 전달 9 생물 의학적 용도로 사용된다 남아있을 수있다. 여기에서는 탄소 나노 튜브가 분산 동원 때문에 약물이 인체 (10) 내에 전달 될 ​​수있는 상태로 유지하는 것이 필수적이다. 한편, 환경 위험을 줄이기 위해, 대수층 및 식수 자원 (11)에 그 입구를 방지하기 위해 탄소 나노 튜브를 고정화하는 방법을 중심으로 연구가 필요하다. 최근의 연구는 살아있는 유기체에 탄소 나노 튜브의 독성 효과를보고도 있기 때문에, 입력하고 먹이 사슬에 축적 탄소 나노 튜브의 관점에서 생태계에 위험했다5,8를 생분해 탄소 나노 튜브는 어렵다. 탄소 나노 튜브의 장벽을 통과하기 위해 탄소 나노 튜브를 함유해도 매립 배리어 시스템을 가진 것이 가능할 수있다. 이러한 경우 탄소 나노 튜브는 지하수 저수지 및 표면 수역에 입력 할 수 있습니다. CNT의 폐기 규정이 잘 정의되지 않고 반송기구가 제대로 이해되는 바와 같이, 탄소 나노 튜브의 이동도의 개선 된 이해를 공식화 및 디자인 적절한 폐기 시스템 (12)에 필요하다. 따라서 CNT 보유를 수정 운명과 다공성 매체에서 탄소 나노 튜브의 수송 및 표면에 지하 환경에 일반적으로 존재하는 물리적, 화학적 요인의 효과를 연구하고 이해하는 것이 중요합니다. 다수의 연구는 다공성 매질에서의 나노 입자의 수송에 입자 (17)의 속도 (16), 및 표면 특성, 유동 콜렉터 입경 13-15의 효과에 대해 수행되었다. 오디오 솔루션의 효과에 그러나 체계적인 조사콜렉터 표면 상으로 가능한 증착에 이온 화학 (예 : pH와 이온 강도 등)는 여전히 18 ~ 20를 제한됩니다. 또한, 물리적 요인, 매체의 솔루션 화학, 탄소 나노 튜브의 표면 특성의 결합에 미치는 영향을 잘 이해하고 다른 문헌에서 변화되지 않습니다. 본 연구에서 다중 벽 탄소 나노 튜브의 표면 개질에 대한 제조 방법은, 산 세정 석영 모래를 충전 체계적인 실험실 규모의 컬럼과 함께 설명 될 것이다하는 포화 된 다공성 지지체의 표면 개질 된 탄소 나노 튜브의 반송, 유지 및 재 이동을 조사하기 위해 사용되는 .

<table><tbody><tr><td>MWCNT</td><td>Cheap Tubes Inc., USA</td><td>sku-03040304</td><td>Purchased as semi-functionlized powder</td></tr><tr><td>Quartz sand</td><td>Sibelco Nordic, Baskarp, Sweden</td><td>B44</td><td>Purchased with more than 91% silica sand</td></tr><tr><td>H&lt;sub&gt;2&lt;/sub&gt;SO&lt;sub&gt;4&lt;/sub&gt;</td><td>VWR</td><td>1.01833.2500</td><td>95%-97% purity</td></tr><tr><td>HNO&lt;sub&gt;3&lt;/sub&gt;</td><td>VWR</td><td>1.00441.1000</td><td>70% purity</td></tr><tr><td>HCl</td><td>VWR</td><td>1.00317.2500</td><td>37%-38% purity</td></tr><tr><td>H&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;2&lt;/sub&gt;</td><td>VWR</td><td>23615.248</td><td>30% purity</td></tr><tr><td>NaCl</td><td>VWR</td><td>1.06404.0500</td><td>99.5% purity</td></tr><tr><td>NaOH</td><td>Sigma-Aldrich</td><td>S8045-500G</td><td>99.99% pur pellets&amp;nbsp;</td></tr><tr><td>Ultrasonic Homogenizer</td><td>Biologics Inc. Manassas, Virginia</td><td>Model 3000, 0-127-0002</td><td>Operated for fix time interval</td></tr><tr><td>Sonicator (bath)</td><td>Kerry Ultrasonic Ltd</td><td>1808</td><td>Common bath sonicator</td></tr><tr><td>Peristaltic pump</td><td>Ismantec, Glattbrugg, Switzerland</td><td>ISM931</td><td>Work with tygon tubing in the pump</td></tr><tr><td>Spectrophotometer</td><td>Hach Lange</td><td>DR500, LPV408.99.0001</td><td>Operate with manual cuvette as well as automated sampling</td></tr><tr><td>pH meter</td><td>Metrohm</td><td>781</td><td>pH analysis</td></tr><tr><td>Glass column</td><td>Chromaflex</td><td>420830-1510</td><td>Column with adjustable cap</td></tr><tr><td>Fraction collector</td><td>Spectrum Labs Europe</td><td>CF-2, 124846</td><td>Fixed at regular interval of time</td></tr><tr><td>Fraction collector tubes</td><td>VWR</td><td>212-9599</td><td>6 ml volume glass tube</td></tr><tr><td>Hot plate stir</td><td>Thermo Scientific</td><td>SP131320-33</td><td>Adjustable tempurature</td></tr><tr><td>Oven</td><td>Elektro Helios</td><td>259</td><td>For oven dry of sand</td></tr><tr><td>Balance</td><td>Mettler Toledo</td><td>AE 160</td><td>For accurate weight</td></tr></tbody></table>

transport of surface-modified carbon nanotubes through a soil column

Carbon nanotubes (CNTs) are widely manufactured nanoparticles, which are being utilized in a number of consumer products, such as sporting goods, electronics and biomedical applications. Due to their accelerating production and use, CNTs constitute a potential environmental risk if they are released to soil and groundwater systems. It is therefore essential to improve the current understanding of environmental fate and transport of CNTs. The transport and retention of CNTs in both natural and artificial media have been reported in literature, but the findings widely vary and are thus not conclusive. There are a number of physical and chemical parameters responsible for variation in retention and transport. In this study, a complete procedure of selected multiwalled carbon nanotubes (MWCNTs) is presented starting from their surface modification to a complete set of laboratory column experiments at critical physical and chemical scenarios. Results indicate that the stability of the commercially available MWCNTs are critical with their attached surface functional group which can also influence the transport and retention of MWCNT through the surrounding medium.

다중 벽 탄소 나노 튜브 기능화의 효과 기능화 MWCNT 분산 용액 용액 평형에 도달 할 수 있도록 비이커에 밀봉 하였다. 초음파 6 개월 (그림 2)에 대한 동일하게 유지 솔루션 MWCNT의 유체 역학적 직경 (1,619 ± 262 ㎚)로 초음파 처리 후 원액에서 관찰도 침강이나 응집이 있었다. 이동성에 다중 벽 탄소 나노 튜브의 작용의 효과를 조사하기 위해, 열 실험의 ?...

Watch this Scientific Journal Video about Transport of Surface-modified Carbon Nanotubes through a Soil Column at JoVE.com

Transport of Surface-modified Carbon Nanotubes through a Soil Column

Surface properties of a nanoparticle are important for their interaction with the surrounding medium. Therefore the surface modification of carbon nanotubes can be critical for their transport and retention through porous media. Here, lab scale column experiments are used to understand the possible transport and retention of these nanoparticles.

토양 칼럼을 통해 표면 개질 된 카본 나노 튜브의 운송

Carbon nanotubes (CNTs) are widely manufactured nanoparticles, which are being utilized in a number of consumer products, such as sporting goods, ...

transport-of-surface-modified-carbon-nanotubes-through-a-soil-column

Research

JoVE Journal

Chemistry

9.5K 조회수.  Nalanda University. Surface properties of a nanoparticle are important for their interaction with the surrounding medium. Therefore the surface modification of carbon nanotubes can be critical for their transport and retention through porous media. Here, lab scale column experiments are used to understand the possible transport and retention of these nanoparticles. 

비디오: Transport of Surface-modified Carbon Nanotubes through a Soil Column

Fabrication, Densification, and Replica Molding of 3D Carbon Nanotube Microstructures

The introduction of new materials and processes to microfabrication has, in large part, enabled many important advances in microsystems, lab-on-a-chip devices, and their applications. In particular, capabilities for cost-effective fabrication of polymer microstructures were transformed by the advent of soft lithography and other micromolding techniques 1, 2, and this led a revolution in applications of microfabrication to biomedical engineering and biology. Nevertheless, it remains challenging to fabricate microstructures with well-defined nanoscale surface textures, and to fabricate arbitrary 3D shapes at the micro-scale. Robustness of master molds and maintenance of shape integrity is especially important to achieve high fidelity replication of complex structures and preserving their nanoscale surface texture. The combination of hierarchical textures, and heterogeneous shapes, is a profound challenge to existing microfabrication methods that largely rely upon top-down etching using fixed mask templates. On the other hand, the bottom-up synthesis of nanostructures such as nanotubes and nanowires can offer new capabilities to microfabrication, in particular by taking advantage of the collective self-organization of nanostructures, and local control of their growth behavior with respect to microfabricated patterns. 
Our goal is to introduce vertically aligned carbon nanotubes (CNTs), which we refer to as CNT "forests", as a new microfabrication material. We present details of a suite of related methods recently developed by our group: fabrication of CNT forest microstructures by thermal CVD from lithographically patterned catalyst thin films; self-directed elastocapillary densification of CNT microstructures; and replica molding of polymer microstructures using CNT composite master molds. In particular, our work shows that self-directed capillary densification ("capillary forming"), which is performed by condensation of a solvent onto the substrate with CNT microstructures, significantly increases the packing density of CNTs. This process enables directed transformation of vertical CNT microstructures into straight, inclined, and twisted shapes, which have robust mechanical properties exceeding those of typical microfabrication polymers. This in turn enables formation of nanocomposite CNT master molds by capillary-driven infiltration of polymers. The replica structures exhibit the anisotropic nanoscale texture of the aligned CNTs, and can have walls with sub-micron thickness and aspect ratios exceeding 50:1. Integration of CNT microstructures in fabrication offers further opportunity to exploit the electrical and thermal properties of CNTs, and diverse capabilities for chemical and biochemical functionalization 3.

We present methods for fabrication of patterned microstructures of vertically aligned carbon nanotubes (CNTs), and their use as master molds for production of polymer microstructures with organized nanoscale surface texture. The CNT forests are densified by condensation of solvent onto the substrate, which significantly increases their packing density and enables self-directed formation of 3D shapes.

3D 카본 나노튜브 Microstructures의 제조, Densification 및 복제 성형

The introduction of new materials and processes to microfabrication has, in large part, enabled many important advances in microsystems, lab-on-a-chip ...

연구

공학

Synthesis and Functionalization of Nitrogen-doped Carbon Nanotube Cups with Gold Nanoparticles as Cork Stoppers

Nitrogen-doped carbon nanotubes consist of many cup-shaped graphitic compartments termed as nitrogen-doped carbon nanotube cups (NCNCs). These as-synthesized graphitic nanocups from chemical vapor deposition (CVD) method were stacked in a head-to-tail fashion held only through noncovalent interactions. Individual NCNCs can be isolated out of their stacking structure through a series of chemical and physical separation processes. First, as-synthesized NCNCs were oxidized in a mixture of strong acids to introduce oxygen-containing defects on the graphitic walls. The oxidized NCNCs were then processed using high-intensity probe-tip sonication which effectively separated the stacked NCNCs into individual graphitic nanocups. Owing to their abundant oxygen and nitrogen surface functionalities, the resulted individual NCNCs are highly hydrophilic and can be effectively functionalized with gold nanoparticles (GNPs), which preferentially fit in the opening of the cups as cork stoppers. These graphitic nanocups corked with GNPs may find promising applications as nanoscale containers and drug carriers.

We discussed the synthesis of individual graphitic nanocups using a series of techniques including chemical vapor deposition, acid oxidation and probe-tip sonication. By citrate reduction of HAuCl4, the graphitic nanocups were effectively corked with gold nanoparticles due to the chemically reactive edges of the cups.

코르크 마개로 금 나노 입자와 질소 도핑 된 탄소 나노 튜브 컵의 합성과 기능화

Nitrogen-doped carbon  nanotubes consist of many cup-shaped graphitic compartments termed as  nitrogen-doped carbon nanotube cups (NCNCs).  These ...

A Whole Cell Bioreporter Approach to Assess Transport and Bioavailability of Organic Contaminants in Water Unsaturated Systems

Bioavailability of contaminants is a prerequisite for their effective biodegradation in soil. The average bulk concentration of a contaminant, however, is not an appropriate measure for its availability; bioavailability rather depends on the dynamic interplay of potential mass transfer (flux) of a compound to a microbial cell and the capacity of the latter to degrade the compound. In water-unsaturated parts of the soil, mycelia have been shown to overcome bioavailability limitations by actively transporting and mobilizing organic compounds over the range of centimeters. Whereas the extent of mycelia-based transport can be quantified easily by chemical means, verification of the contaminant-bioavailability to bacterial cells requires a biological method. Addressing this constraint, we chose the PAH fluorene (FLU) as a model compound and developed a water unsaturated model microcosm linking a spatially separated FLU point source and the FLU degrading bioreporter bacterium Burkholderia sartisoli RP037-mChe by a mycelial network of Pythium ultimum. Since the bioreporter expresses eGFP in response of the PAH flux to the cell, bacterial FLU exposure and degradation could be monitored directly in the microcosms via confocal laser scanning microscopy (CLSM). CLSM and image analyses revealed a significant increase of the eGFP expression in the presence of P. ultimum compared to controls without mycelia or FLU thus indicating FLU bioavailability to bacteria after mycelia-mediated transport. CLSM results were supported by chemical analyses in identical microcosms. The developed microcosm proved suitable to investigate contaminant bioavailability and to concomitantly visualize the involved bacteria-mycelial interactions.

A whole cell bioreporter assay with Burkholderia sartisoli RP037-mChe was developed to detect fractions of an organic contaminant (i.e., fluorene) available for bacterial degradation after active transport by mycelia bridging air-filled pores in a water unsaturated model system.

전체 셀 Bioreporter 접근 물 불포화 시스템에서 유기 오염 물질의 운송과 생체 이용률을 평가하기 위해

Bioavailability of contaminants is a prerequisite for their effective biodegradation in soil. The average bulk concentration of a contaminant, however, is ...

환경과학

Facile Preparation of Internally Self-assembled Lipid Particles Stabilized by Carbon Nanotubes

We present a facile method to prepare nanostructured lipid particles stabilized by carbon nanotubes (CNTs). Single-walled (pristine) and multi-walled (functionalized) CNTs are used as stabilizers to produce Pickering type oil-in-water (O/W) emulsions. Lipids namely, Dimodan U and Phytantriol are used as emulsifiers, which in excess water self-assemble into the bicontinuous cubic Pn3m phase. This highly viscous phase is fragmented into smaller particles using a probe ultrasonicator in presence of conventional surfactant stabilizers or CNTs as done here. Initially, the CNTs (powder form) are dispersed in water followed by further ultrasonication with the molten lipid to form the final emulsion. During this process the CNTs get coated with lipid molecules, which in turn are presumed to surround the lipid droplets to form a particulate emulsion that is stable for months. The average size of CNT-stabilized nanostructured lipid particles is in the submicron range, which compares well with the particles stabilized using conventional surfactants. Small angle X-ray scattering data confirms the retention of the original Pn3m cubic phase in the CNT-stabilized lipid dispersions as compared to the pure lipid phase (bulk state). Blue shift and lowering of the intensities in characteristic G and G&#39; bands of CNTs observed in Raman spectroscopy characterize the interaction between CNT surface and lipid molecules. These results suggest that the interactions between the CNTs and lipids are responsible for their mutual stabilization in aqueous solutions. As the concentrations of CNTs employed for stabilization are very low and lipid molecules are able to functionalize the CNTs, the toxicity of CNTs is expected to be insignificant while their biocompatibility is greatly enhanced. Hence the present approach finds a great potential in various biomedical applications, for instance, for developing hybrid nanocarrier systems for the delivery of multiple functional molecules as in combination therapy or polytherapy.

We report on a smart application of carbon nanotubes for kinetic stabilization of lipid particles that contain self-assembled nanostructures in their cores. The preparation of lipid particles requires rather low concentrations of carbon nanotubes permitting their use in biomedical applications such as drug delivery.

탄소 나노 튜브에 의해 안정화 내부 자기 조립 된 지질 입자의 용이 한 제조

We present a facile method to prepare nanostructured lipid particles stabilized by carbon nanotubes (CNTs). Single-walled (pristine) and multi-walled ...

화학

Fabrication of Low Temperature Carbon Nanotube Vertical Interconnects Compatible with Semiconductor Technology

We demonstrate a method for the low temperature growth (350 &#176;C) of vertically-aligned carbon nanotubes (CNT) bundles on electrically conductive thin-films. Due to the low growth temperature, the process allows integration with modern low-&#954; dielectrics and some flexible substrates. The process is compatible with standard semiconductor fabrication, and a method for the fabrication of electrical 4-point probe test structures for vertical interconnect test structures is presented. Using scanning electron microscopy the morphology of the CNT bundles is investigated, which demonstrates vertical alignment of the CNT and can be used to tune the CNT growth time. With Raman spectroscopy the crystallinity of the CNT is investigated. It was found that the CNT have many defects, due to the low growth temperature. The electrical current-voltage measurements of the test vertical interconnects displays a linear response, indicating good ohmic contact was achieved between the CNT bundle and the top and bottom metal electrodes. The obtained resistivities of the CNT bundle are among the average values in the literature, while a record-low CNT growth temperature was used.

A method for the growth of low temperature vertically-aligned carbon nanotubes, and the subsequent fabrication of vertical interconnect electrical test structures using semiconductor fabrication is presented.

반도체 기술과 호환 저온 탄소 나노 튜브 수직 상호 연결의 제작

We demonstrate a method for the low temperature growth (350 &#176;C) of vertically-aligned carbon nanotubes (CNT) bundles on electrically conductive ...

Functionalization of Single-walled Carbon Nanotubes with Thermo-reversible Block Copolymers and Characterization by Small-angle Neutron Scattering

We demonstrate a protocol for single-walled carbon nanotube functionalization using thermo-sensitive PEO-PPO-PEO triblock copolymers in an aqueous solution. In a carbon nanotube/PEO105-PPO70-PEO105 (poloxamer 407) aqueous solution, the amphiphilic poloxamer 407 adsorbs onto the carbon nanotube surfaces and self-assembles into continuous layers, driven by intermolecular interactions between constituent molecules. The addition of 5-methylsalicylic acid changes the self-assembled structure from spherical-micellar to a cylindrical morphology. The fabricated poloxamer 407/carbon nanotube hybrid particles exhibit thermo-responsive structural features so that the density and thickness of poloxamer 407 layers are also reversibly controllable by varying temperature. The detailed structural properties of the poloxamer 407/carbon nanotube particles in suspension can be characterized by small-angle neutron scattering experiments and model fit analyses. The distinct curve shapes of the scattering intensities depending on temperature control or addition of aromatic additives are well described by a modified core-shell cylinder model consisting of a carbon nanotube core cylinder, a hydrophobic shell, and a hydrated polymer layer. This method can provide a simple but efficient way for the fabrication and in-situ characterization of carbon nanotube-based nano particles with a structure-tunable encapsulation.

A method for the functionalization of carbon nanotubes with structure-tunable polymeric encapsulation layers and structural characterization using small-angle neutron scattering is presented.

작은 각도 중성자 산란에 의한 열 가역적 블록 공중 합체 및 특성 단일 벽 탄소 나노 튜브의 기능화

We demonstrate a protocol for single-walled carbon nanotube functionalization using thermo-sensitive PEO-PPO-PEO triblock copolymers in an aqueous ...

Repression of Multiple Myeloma Cell Growth In Vivo by Single-wall Carbon Nanotube (SWCNT)-delivered MALAT1 Antisense Oligos

The single-wall carbon nanotube (SWCNT) is a new type of nanoparticle, which has been used to deliver multiple kinds of drugs into cells, such as proteins, oligonucleotides, and synthetic small-molecule drugs. The SWCNT has customizable dimensions, a large superficial area, and can flexibly bind with drugs through different modifications on its surface; therefore, it is an ideal system to transport drugs into cells. Long noncoding RNAs (lncRNAs) are a cluster of noncoding RNA longer than 200 nt, which cannot be translated to protein but play an important role in biological and pathophysiological processes. Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is a highly conserved lncRNA. It was demonstrated that higher MALAT1 levels are related to the poor prognosis of various cancers, including multiple myeloma (MM). We have revealed that MALAT1 regulates DNA repair and cell death in MM; thus, MALAT1 can be considered as a therapeutic target for MM. However, the efficient delivery of the antisense oligo to inhibit/knockdown MALAT1 in vivo is still a problem. In this study, we modify the SWCNT with PEG-2000 and conjugate an anti-MALAT1 oligo to it, test the delivery of this compound in vitro, inject it intravenously into a disseminated MM mouse model, and observe a significant inhibition of MM progression, which indicates that SWCNT is an ideal delivery shuttle for anti-MALAT1 gapmer DNA.

Repression of Multiple Myeloma Cell Growth In Vivo by Single-wall Carbon Nanotube SWCNT-delivered MALAT1 Antisense Oligos

This manuscript describes the synthesis of a single-wall carbon nanotube (SWCNT)-conjugated MALAT1 antisense gapmer DNA oligonucleotide (SWCNT-anti-MALAT1), which demonstrates the reliable delivery of the SWCNT and the potent therapeutic effect of anti-MALAT1 in vitro and in vivo. Methods used for synthesis, modification, conjugation, and injection of SWCNT-anti-MALAT1 are described.

단일 벽 탄소 나노튜브 (SWCNT)에 의해 생체 내에서 여러 Myeloma 세포 성장 억압-MALAT1 센스 Oligos 전달

The single-wall carbon nanotube (SWCNT) is a new type of nanoparticle, which has been used to deliver multiple kinds of drugs into cells, such as ...

암 연구학

Localization and Relative Quantification of Carbon Nanotubes in Cells with Multispectral Imaging Flow Cytometry

Carbon-based nanomaterials, like carbon nanotubes (CNTs), belong to this type of nanoparticles which are very difficult to discriminate from carbon-rich cell structures and de facto there is still no quantitative method to assess their distribution at cell and tissue levels. What we propose here is an innovative method allowing the detection and quantification of CNTs in cells using a multispectral imaging flow cytometer (ImageStream, Amnis). This newly developed device integrates both a high-throughput of cells and high resolution imaging, providing thus images for each cell directly in flow and therefore statistically relevant image analysis. Each cell image is acquired on bright-field (BF), dark-field (DF), and fluorescent channels, giving access respectively to the level and the distribution of light absorption, light scattered and fluorescence for each cell. The analysis consists then in a pixel-by-pixel comparison of each image, of the 7,000-10,000 cells acquired for each condition of the experiment. Localization and quantification of CNTs is made possible thanks to some particular intrinsic properties of CNTs: strong light absorbance and scattering; indeed CNTs appear as strongly absorbed dark spots on BF and bright spots on DF with a precise colocalization.
This methodology could have a considerable impact on studies about interactions between nanomaterials and cells given that this protocol is applicable for a large range of nanomaterials, insofar as they are capable of absorbing (and/or scattering) strongly enough the light.

In this study, the main purpose was to monitor the cellular uptake and eventual exocytosis of carbon nanotubes (CNTs). From this perspective, we proposed here a unique method using multispectral imaging flow cytometry allowing a quantification and localization of CNTs in a statistically relevant number of cells.

멀티 스펙트럼 이미징 유동 세포 계측법과 세포의 현지화 및 탄소 나노 튜브의 상대 정량

Carbon-based nanomaterials, like carbon nanotubes (CNTs), belong to this type of nanoparticles which are very difficult to discriminate from carbon-rich ...

생체공학

Precision Milling of Carbon Nanotube Forests Using Low Pressure Scanning Electron Microscopy

A nanoscale fabrication technique appropriate for milling carbon nanotube (CNT) forests is described. The technique utilizes an environmental scanning electron microscope (ESEM) operating with a low pressure water vapor ambient. In this technique, a portion of the electron beam interacts with the water vapor in the vicinity of the CNT sample, dissociating the water molecules into hydroxyl radicals and other species by radiolysis. The remainder of the electron beam interacts with the CNT forest sample, making it susceptible to oxidation from the chemical products of radiolysis. This technique may be used to trim a selected region of an individual CNT, or it may be used to remove hundreds of cubic microns of material by adjusting ESEM parameters. The machining resolution is similar to the imaging resolution of the ESEM itself. The technique produces only small quantities of carbon residue along the boundaries of the cutting zone, with minimal effect on the native structural morphology of the CNT forest.

Low pressure scanning electron microscopy in a water vapor ambient is used to machine nanoscale to microscale features in carbon nanotube forests.

저압 주사 전자 현미경을 사용하여 탄소 나노 튜브 숲의 정밀 밀링

A nanoscale fabrication technique appropriate for milling carbon nanotube (CNT) forests is described. The technique utilizes an environmental scanning ...

식물에 대한 효율적인 생체 분자 및 염료 전달을 위한 탄소 나노섬유 어레이 사용

Using Vertically Aligned Carbon Nanofiber Arrays on Rigid or Flexible Substrates for Delivery of Biomolecules and Dyes to Plants

The delivery of biomolecules and impermeable dyes to intact plants is a major challenge. Nanomaterials are up-and-coming tools for the delivery of DNA to plants. As exciting as these new tools are, they have yet to be widely applied. Nanomaterials fabricated on rigid substrate (backing) are particularly difficult to successfully apply to curved plant structures. This study describes the process for microfabricating vertically aligned carbon nanofiber arrays and transferring them from a rigid to a flexible substrate. We detail and demonstrate how these fibers (on either rigid or flexible substrates) can be used for transient transformation or dye (e.g., fluorescein) delivery to plants. We show how VACNFs can be transferred from rigid silicon substrate to a flexible SU-8 epoxy substrate to form flexible VACNF arrays. To overcome the hydrophobic nature of SU-8, fibers in the flexible film were coated with a thin silicon oxide layer (2-3 nm). To use these fibers for delivery to curved plant organs, we deposit a 1 &#181;L droplet of dye or DNA solution on the fiber side of VACNF films, wait 10 min, place the films on the plant organ and employ a swab with a rolling motion to drive fibers into plant cells. With this method, we have achieved dye and DNA delivery in plant organs with curved surfaces.

저자 스포트라이트: 탄소 나노섬유 어레이를 통한 혁신을 통한 플랜트 변화 실현 

Here we describe methods for microfabricating vertically aligned carbon nanofibers (VACNFs), transferring VACNFs to flexible substrates, and applying VACNFs on both rigid and flexible substrates to plants for biomolecule and dye delivery.

생체분자 및 염료를 식물에 전달하기 위해 단단하거나 유연한 기판에 수직으로 정렬된 탄소 나노섬유 어레이 사용

The delivery of biomolecules and impermeable dyes to intact plants is a major challenge. Nanomaterials are up-and-coming tools for the delivery of DNA to ...