蛇形流道中微粒惯性聚焦及细胞操控技术

Particle Inertial Focusing and Cell Manipulation Technology in Serpentine Channel

惯性微流控技术作为一种被动式操控微粒的技术,广泛应用于生物医学领域。基于惯性聚焦原理,设计了两种不同宽高比的非对称蛇形流道的微流控芯片,以研究宽高比、流道长度和流体体积流量对微粒惯性聚焦行为的影响。使用软光刻与等离子体键合工艺制作芯片,研究了粒径15μm聚苯乙烯荧光粒子在蛇形流道中的惯性聚焦特性,以及该芯片操控H1299人非小细胞肺癌细胞的效果。结果表明:在宽高比为4∶1的蛇形微流道中,粒子在体积流量为100μL/min时产生单列聚焦。在宽高比为3∶1的蛇形微流道中,粒子在体积流量为10μL/min时即可产生单列聚焦,且粒子在低宽高比流道中仅需更短的流道即可实现聚焦。此外,随着体积流量的增大,粒子的聚焦位置逐步向外壁面迁移。最后,验证了H1299细胞在低宽高比流道中的单列聚焦与排列操控的可行性。该研究结果表明低宽高比的非对称蛇形流道更易于粒子惯性聚焦,且通过优化流道结构与体积流量可实现生物细胞的精确惯性操控。

As a passive technology for particle manipulation,inertial microfluidic technology is widely used in the field of biomedicine.Based on the principle of inertial focusing,two kinds of microfluidic chips with asymmetric serpentine channels with different aspect ratios were designed,and the effects of aspect ratio,channel length and fluid volume flow on the inertial focusing behavior of particles were studied.The chip was fabricated by soft lithography and plasma bonding technologies,and the inertial focusing characteristic of polystyrene fluorescent particles with a particle size of 15μm in the serpentine channel and the effect of the chip to manipulate H1299 human non-small cell lung cancer cells were studied.The results show that the particles focus in a line at a volume flow of 100μL/min in the serpentine channel with an aspect ratio of 4∶1,while the particles focus in a line at a volume flow of 10μL/min in the serpentine channel with an aspect ratio of 3∶1.In low aspect ratio channels,particles need only shorter flow channels to achieve focus.In addition,with the increase of the volume flow,the focusing position of particles gradually migrates towards the outer wall.Finally,the manipulation feasibility of focusing in a line and alignment manipulation of H1299 cell was verified in the channel with low aspect ratio.The research result shows that the asymmetric serpentine channel with low aspect ratio is more prone to particle inertial focusing,and precise inertial manipulation of biological cells can be realized through optimizing the channel structure and volume flow.