高通量单分散纳升 /皮升液滴的制备在数字 PCR、质谱分析、细胞筛选等生物医学领域至关重要, 而现有的技术制备速率只能达到 1 000/s。本文提出了一种离心力与微喷嘴阵列相结合的微流控芯片, 实现了超高通量液滴的制备。首先, 对离心液滴微流控芯片进行设计, 通过有限元仿真详细分析了微喷嘴尺寸、离心加速度和流量等参数对液滴尺寸的影响, 获得了纳升级液滴芯片的设计参数, 使用微纳加工方法制作离心式液滴生成芯片, 并进行了液滴的高通量生成实验。实验与仿真结果表明: 液滴尺寸与离心加速度成反向关系, 与微喷嘴尺寸成正向关系, 并在很大的流量范围内液滴尺寸基本不变, 表现出优异的鲁棒性。本液滴生成芯片在离心加速度 250g~500g下, 可制备液滴直径为 105~145 μm, 制备速率达 27 000个/s, 且直径一致性良好( CV<3%), 证明本液滴生成芯片具有超高通量的特点。

High throughput monodisperse nano-liter/pico-liter droplet emulsions are essential in several biomedical applications, such as droplet digital PCR, mass spectrometry, and cell sorting. However, the preparation rate of existing technologies can only reach 1 000/s, which restricts development of the bio. medical field. We present a novel technology for providing monodisperse droplets with high throughput us. ing centrifugal force and a micro-nozzle array. First, we designed the centrifugal droplet microfluidic chip and studied the relationships of droplet diameters with dimensions of the micro-nozzle, centrifugal accelera. tion, and flow rate based on simulation of the droplets’generation using the micro-nozzle;based on these, we obtained optimized design parameters for generating 1-nL droplets. Then, a microfluidic chip was fabri. cated using standard lithography. Finally, high throughput droplet generation was performed. The experi. mental and simulation results indicate that the droplet size is inversely related to the centrifugal acceleration and directly proportional to the micro-nozzle size. The droplet size is stable in a large range of flow rate, which indicates excellent robustness. Homogenous droplets with pre-selectable diameters in a range from 105 to 145 μm were generated with a coefficient of variation of 3% and generation rate of 27 000/s under a cen. trifugalaccelerationrangeof250g to500g, demonstratingultra-high throughputcharacteristicsofthechip.