Institute of Mechanical Systems, Department of Mechanical and Process Engineering, Swiss Federal Institute of Technology (ETH) , Tannenstr. 3, CH-8092 Zurich, Switzerland.
Biomicrofluidics. 2015 Mar 31;9(2):024109. doi: 10.1063/1.4916780. eCollection 2015 Mar.
Recent years have witnessed a strong trend towards analysis of single-cells. To access and handle single-cells, many new tools are needed and have partly been developed. Here, we present an improved version of a single-cell printer which is able to deliver individual single cells and beads encapsulated in free-flying picoliter droplets at a single-bead efficiency of 96% and with a throughput of more than 10 beads per minute. By integration of acoustophoretic focusing, the cells could be focused in x and y direction. This way, the cells were lined-up in front of a 40 μm nozzle, where they were analyzed individually by an optical system prior to printing. In agreement with acoustic simulations, the focusing of 10 μm beads and Raji cells has been achieved with an efficiency of 99% (beads) and 86% (Raji cells) to a 40 μm wide center region in the 1 mm wide microfluidic channel. This enabled improved optical analysis and reduced bead losses. The loss of beads that ended up in the waste (because printing them as single beads arrangements could not be ensured) was reduced from 52% ± 6% to 28% ± 1%. The piezoelectric transducer employed for cell focusing could be positioned on an outer part of the device, which proves the acoustophoretic focusing to be versatile and adaptable.
近年来，单细胞分析的趋势愈加强劲。为了获取和处理单细胞，需要开发许多新的工具，其中部分工具已经开发出来。在这里，我们展示了一种改进型单细胞打印机，它能够以 96%的单珠效率和超过每分钟 10 个珠的通量，输送单个单细胞和自由飞行皮升级液滴中包裹的珠。通过声聚焦的集成，细胞可以在 x 和 y 方向上聚焦。这样，细胞在 40 μm 喷嘴前排列，在打印之前通过光学系统对其进行单独分析。与声学模拟一致，已经实现了 10 μm 珠和 Raji 细胞的 99%（珠）和 86%（Raji 细胞）的高效聚焦，聚焦到 1mm 宽微流道中的 40 μm 宽中心区域。这使得光学分析得到了改善，并且减少了珠的损失。由于无法确保将它们打印成单个珠的排列，因此最终进入废物的珠的损失（因为无法确保将它们打印成单个珠的排列）从 52%±6%减少到 28%±1%。用于细胞聚焦的压电换能器可以定位在设备的外部，这证明了声聚焦具有多功能性和适应性。
