Kang Wonmo, McNaughton Rebecca L, Yavari Fazel, Minary-Jolandan Majid, Safi Asmahan, Espinosa Horacio D
1Department of Mechanical Engineering, Northwestern University, Evanston, IL, USA.
J Lab Autom. 2014 Feb;19(1):100-9. doi: 10.1177/2211068213495395. Epub 2013 Jul 29.
This brief report describes a novel tool for microfluidic patterning of biomolecules and delivery of molecules into cells. The microdevice is based on integration of nanofountain probe (NFP) chips with packaging that creates a closed system and enables operation in liquid. The packaged NFP can be easily coupled to a micro/nano manipulator or atomic force microscope for precise position and force control. We demonstrate here the functionality of the device for continuous direct-write parallel patterning on a surface in air and in liquid. Because of the small volume of the probes (~3 pL), we can achieve flow rates as low as 1 fL/s and have dispensed liquid drops with submicron to 10 µm diameters in a liquid environment. Furthermore, we demonstrate that this microdevice can be used for delivery of molecules into single cells by transient permeabilization of the cell membrane (i.e., electroporation). The significant advantage of NFP-based electroporation compared with bulk electroporation and other transfection techniques is that it allows for precise and targeted delivery while minimizing stress to the cell. We discuss the ongoing development of the tool toward automated operation and its potential as a multifunctional device for microarray applications and time-dependent single-cell studies.
本简短报告描述了一种用于生物分子微流控图案化以及将分子递送至细胞的新型工具。该微型装置基于纳米喷泉探针（NFP）芯片与封装的集成，形成了一个封闭系统并能在液体中操作。封装后的NFP可轻松连接至微/纳米操纵器或原子力显微镜，以实现精确的位置和力控制。我们在此展示了该装置在空气和液体环境中对表面进行连续直写平行图案化的功能。由于探针体积小（约3皮升），我们能够实现低至1飞升/秒的流速，并在液体环境中 dispense 出直径从亚微米到10微米的液滴。此外，我们证明了这种微型装置可通过细胞膜的瞬时通透化（即电穿孔）用于将分子递送至单个细胞。与批量电穿孔和其他转染技术相比，基于NFP的电穿孔的显著优势在于它允许进行精确且有针对性的递送，同时将对细胞的压力降至最低。我们讨论了该工具朝着自动化操作的持续发展及其作为用于微阵列应用和时间依赖性单细胞研究的多功能装置的潜力。 （注：原文中“dispensed”未准确翻译，根据语境推测可能是“喷出、 dispense 出”等意思，这里保留英文待进一步确认准确含义）
