Nanoscale Science and Engineering Center for Affordable Nanoengineering of Polymeric Biomedical Devices, The Ohio State University, Columbus, Ohio 43210, USA.
Phys Rev Lett. 2010 Jul 9;105(2):027802. doi: 10.1103/PhysRevLett.105.027802.
This work obtains the first molecular imaging of wall slip in entangled solutions. Using a combination of confocal fluorescence microscopy and rheometry, molecular images were captured in the nonlinear response regime of entangled DNA solutions. Conformations of DNA molecules were imaged during shear to correlate with the magnitude of wall slip. Interfacial chain disentanglement results in wall slip beyond the stress overshoot. Sufficient disentanglement can produce tumbling of individual DNA in the entangled solutions.
这项工作首次实现了缠结溶液壁滑移的分子成像。通过共聚焦荧光显微镜和流变仪的结合，在缠结 DNA 溶液的非线性响应区获得了分子图像。在剪切过程中对 DNA 分子构象进行成像，以与壁滑移的幅度相关联。界面链解缠导致超过应力过冲的壁滑移。充分的解缠可以使缠结溶液中的单个 DNA 发生翻滚。
