P612
886-2-2789-6761
cfchou [at] phys.sinica.edu.tw
P612
886-2-2789-6761
cfchou [at] phys.sinica.edu.tw
Chu, Michelle / 886-2-2789-8364
(1) | 國內學術研究獎項 | 2014-04 | 2013 科技部傑出研究獎 Outstanding Research Award of Ministry of Science and Technology |
(1) | 西元年:2020 研究人員(中):周家復、葉佳唯,A. Taloni, K.K. Sriram, 沈介磐,高德佑 研究人員(英):CHOU, CHIA-FU, J.W. Yeh, A. Taloni, K.K. Sriram, J.P. Shen, D.Y. Kao 研究成果名稱(中):奈米侷限性誘導之DNA蛇行運動及其類比於擾動之界面 研究成果名稱(英):Nanoconfinement-induced DNA reptating motion and analogy to fluctuating interfaces 簡要記述(中):糾纏環境中的巨分子被限制為主要沿著約束管蠕動,從而引致所謂的蛇行或管狀運動。儘管近年來高分子物理學有長足進步,已深入了解其型態動力學,但蛇行“管徑”之定量表徵及分析仍是一個懸而未決的問題。本研究使用空間上極度受限的平行板奈米狹縫(高度至小於30 奈米),我們可直接觀察在一維侷限奈米環境下的DNA蛇行運動。通過引入分段式切向向量及其關聯函數,我們首次提供了一種定量的分析方法,來表徵高分子鏈的蛇行並連結其與受侷限度的關係。結果表明,其橫向擾動的幅度(虛擬二維“管”)亦展現和下列現象相似之規度律,如:擾動之界面,接觸線,或電荷密度波等,而其粗糙度指數則取決於狹縫高度。我們的研究結果顯示,在較淺的奈米狹縫中DNA擾動的介面較不粗糙。我們預期此分析方式將成為進一步了解高分子物理與其他非平衡態物理系統之間關聯性的起點。 簡要記述(英):Macromolecules in an entangled environment are constrained to wriggle predominantly along a confining tube, giving rise to the so-called reptation or tube-like motion. While the principles of polymer physics were well developed to understand its conformational dynamics, the quantitative characterization of the tube diameter and resulting reptation remains an open question. Here, using highly confined parallel plate geometry nanoslits down to sub-30 nm, we directly observe reptation in a one-dimensional (1D) confined nano-environment. For the first time, we provide a quantitative analysis scheme, by introducing the segmental tangential vector and its associated correlation function, to characterize the strand reptation and connect it to the confinement degree. Our analysis shows that the amplitude of the transverse fluctuations (the virtual 2D “tube”) exhibits the typical scaling of fluctuating interfaces, contact lines, or charge density waves, with a roughness exponent, which depends on the slit height. Our results are shown to lead to less rough DNA profiles in shallower nanoslits. We anticipate our analysis to be a starting point for a more detailed understanding of the relationship between polymer physics and other nonequilibrium physical systems.
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(2) | 西元年:2012 研究人員(中):周家復、葉佳唯、Alessandro Taloni、陳彥龍 研究人員(英):CHOU, CHIA-FU, Jia-Wei Yeh, Alessandro Taloni, Yeng-Long Chen 研究成果名稱(中):微奈米流道介面熵力驅動之單分子DNA拔河 研究成果名稱(英):Entropy-driven single molecule tug-of-war of DNA at micro-nanofluidic interfaces 簡要記述(中):熵驅動的高分子動力學在生物系統中是極其重要的,但在奈米尺度上的熵力及其對奈米侷限度的相依性仍然是不清楚的。在這裡,我們建立了一個由熵力驅動的單分子DNA拔河系統,該系統由一個奈米狹縫橋接兩個微奈米流道的界面組成。由此系統,我們在不需施加外力的情況下,便可研究奈米尺度下,生物分子的熵力及其對奈米侷限度的相依性及其規度律。我們的結果提供了直接的實驗證據表明,熵力祇和分子在奈米尺度的空間侷限(即狹縫高度)相關,而和狹縫長度和在其內的DNA長度無關。我們的研究結果對高分子聚合物在奈米尺度的傳輸現象,單分子分析的系統設計上,及生物科技上均有潛在的應用性。 簡要記述(英):Entropy-driven polymer dynamics at the nanoscale is fundamentally important in biological systems but the dependence of the entropic force on the nanoconfinement remains elusive. Here we established an entropy-driven single molecule tug-of-war (TOW) at two micro-nanofluidic interfaces bridged by a nanoslit, performed the force analysis from a modified worm-like chain in the TOW scenario and the entropic recoiling process, and determined the associated scalings on the nanoconfinement. Our results provide a direct experimental evidence that the entropic forces in these two regimes, though unequal, are essentially constant at defined slit heights, irrespective of the slit lengths and the DNA segments within. Our findings have the implications to polymer transport at the nanoscale, device design for single molecule analysis, and biotechnological applications.
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(3) | 西元年:2012 研究人員(中):周家復、廖國棠 研究人員(英):CHOU, CHIA-FU, Kuo-Tang Liao 研究成果名稱(中):奈米分子阱和分子壩應用於高導電度緩衝液內超快速之蛋白質富集(濃縮) 研究成果名稱(英):Nanoscale molecular traps and dams for ultrafast protein enrichment in high-conductivity buffers 簡要記述(中):我們提出一個新的分子富集的方法,稱為分子壩,該方法可在生理緩衝液內,以奈米尺度的無電極式介電泳,快速達到蛋白質富集與濃縮。我們以絕緣材料製作了奈米流道,並在其中嵌製30奈米大小的間隙,作為聚焦電場的透鏡,在結合微奈米流道界面時,可將外加電場放大約10萬倍。藉由這個奈米間隙聚焦的強電場和其場梯度,並利用分子壩的效應,我們達到快速濃縮蛋白質的效果,在20秒內便可濃縮至少10萬倍,比以往文獻報告的方法快了幾個數量級。我們的研究開闢了奈米級分子水壩的可能應用,包括以微型化感測平台快速且靈敏的分析蛋白質和發現生物標誌物,或應用於沉澱研究和蛋白質結晶學,並可能進一步擴展到小分子的富集或篩選。 簡要記述(英):We report a new approach, termed molecular dam, to enhance mass transport for protein enrichment in nanofluidic channels by nanoscale electrodeless dielectrophoresis under physiological buffer conditions. Dielectric nanoconstrictions, down to 30nm in size, embedded in nanofluidic device, serve as field focusing lens capable of magnifying the applied field to 100000-fold when combined with a micro-to-nanofluidic step interface. Empowered by this strong field and the associated field gradient occurred at the nanoconstrictions, we demonstrate proteins are enriched by molecular damming effect, faster than the trapping effect, to greater than 100000-fold in 20 seconds, which is orders of magnitude faster than most reported methods. Our study opens up further possibilities of using nanoscale molecular dams in miniaturized sensing plat-forms for rapid and sensitive protein analysis and biomarker discovery, with potential applications in precipitation studies and protein crystallization, and possible extensions to small molecules enrichment or screening.
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