Lei Xin, Zhang Jiayan, Hong Hao, Yuan Zhishan, Liu Zewen
School of Chemistry, Beihang University, Beijing 100191, China.
School of Integrated Circuits, Tsinghua University, Beijing 100084, China.
Micromachines (Basel). 2022 Jun 10;13(6):923. doi: 10.3390/mi13060923.
Nanopores have attracted widespread attention in DNA sequencing and protein or biomarker detection, owning to the single-molecule-scale detection accuracy. Despite the most use of naturally biological nanopores before, solid-state nanopores are widely developed with strong robustness, controllable sizes and geometries, a wide range of materials available, as well as flexible manufacturing. Therefore, various techniques typically based on focused ion beam or electron beam have been explored to drill nanopores directly on free-standing nanofilms. To further reduce and sculpt the pore size and shape for nano or sub-nano space-time sensing precision, various controllable shrinking technologies have been employed. Correspondingly, high-energy-beam-induced contraction with direct visual feedback represents the most widely used. The ability to change the pore diameter was attributed to surface tension induced original material migration into the nanopore center or new material deposition on the nanopore surface. This paper reviews typical solid-state nanopore shrinkage technologies, based on the careful summary of their principles and characteristics in particularly size and morphology changes. Furthermore, the advantages and disadvantages of different methods have also been compared completely. Finally, this review concludes with an optimistic outlook on the future of solid-state nanopores.
纳米孔因其单分子尺度的检测精度，在DNA测序以及蛋白质或生物标志物检测方面受到了广泛关注。尽管此前大多使用天然生物纳米孔，但固态纳米孔由于具有强大的稳健性、可控的尺寸和几何形状、种类繁多的可用材料以及灵活的制造工艺，得到了广泛发展。因此，人们探索了各种通常基于聚焦离子束或电子束的技术，以在独立的纳米薄膜上直接钻出纳米孔。为了进一步减小并塑造孔径和形状，以实现纳米或亚纳米时空传感精度，人们采用了各种可控收缩技术。相应地，具有直接视觉反馈的高能束诱导收缩是应用最为广泛的。孔径变化的能力归因于表面张力导致原始材料迁移到纳米孔中心或新材料沉积在纳米孔表面。本文在仔细总结典型固态纳米孔收缩技术在尺寸和形态变化方面的原理及特点的基础上，对其进行了综述。此外，还全面比较了不同方法的优缺点。最后，本综述对固态纳米孔的未来发展持乐观态度。
