Department of Chemical Engineering, Northeastern University, Boston, Massachusetts 02115, USA.
Lab Chip. 2017 Sep 26;17(19):3234-3239. doi: 10.1039/c7lc00676d.
Controlled alignment of long DNA nanofibers is challenging. This communication reports a method to align human genomic DNA with nearly unlimited length using lithographically produced micro-patterns of self-assembled monolayers (SAMs) with positively charged terminal groups. The micro-patterns act as local DNA reservoirs to supply DNAs for nanofiber formation, and can also stretch and align DNA nanofibers to form an ordered array by controlling the dewetting profile. By reducing the size and inter-patch distance of a micro-patch, a nearly uniform array of long DNA nanofibers can be patterned over a large area. A controlled motion of a DNA containing droplet allows for free patterning of DNA nanofibers and production of complex structures without a transfer process. Bending of DNA nanofibers due to local distortion of the contact line bridges more adjacent micro-patches and increases the chance of producing continuous nanofibers. The interplay between surface tension and electrostatic attraction of positively charged micro-patterns allows the production of long DNA nanofibers in a simple yet powerful way.
长 DNA 纳米纤维的定向排列具有挑战性。本通讯报道了一种使用带有正电荷端基的自组装单层（SAM）光刻微图案来排列人基因组 DNA 的方法，其长度几乎没有限制。微图案充当局部 DNA 储库，为纳米纤维形成提供 DNA，并且还可以通过控制去湿轮廓拉伸和排列 DNA 纳米纤维，以形成有序排列。通过减小微图案的尺寸和图案之间的距离，可以在较大的区域上图案化出几乎均匀的长 DNA 纳米纤维阵列。包含 DNA 的液滴的受控运动允许 DNA 纳米纤维的自由图案化，并且无需转移过程即可生产复杂结构。由于接触线局部变形引起的 DNA 纳米纤维的弯曲桥接更多相邻的微图案，并增加了产生连续纳米纤维的机会。带正电荷的微图案的表面张力和静电力之间的相互作用以简单而强大的方式允许长 DNA 纳米纤维的生产。
