C. elegans is a leading model organism for addressing many fundamental biology issues. Sufficient quantities of the worms with specific developmental stage are needed in C. elegans studies due to the size-dependent features shown in C. elegans. In this work, we presented a simple and feasible microfluidic chip to realize simultaneous sorting of C. elegans with different sizes by graduated microfilters. The micro-device was fabricated with PDMS-agarose hybrid layers consisting of 5 arrays of geometrically optimized square columns as microfilters for separating worms of different sizes. Fluid flow and electric field were simultaneously applied to drive the worms to rapidly and directionally pass through the microfilters, resulting in increased sorting efficiency and accuracy. Further, the sorted worms could be easily collected from 4 grooves of the agarose layer by slipping the PDMS layer to the top of grooves. With this sorting strategy, we demonstrated the feasibility of simultaneously sorting different sizes of C. elegans with high efficiency and accuracy (>95%) and throughput of hundreds of worms per minute. Therefore, the micro-device could be a promising tool to C. elegans assays that need a large number of stage-synchronized worms. It could also be useful for body size-based mutant screening and taxis-response studies in C. elegans.

秀丽隐杆线虫是解决许多基本生物学问题的领先模型生物。由于秀丽隐杆线虫显示出与大小有关的特征，因此秀丽隐杆线虫研究需要足够数量的具有特定发育阶段的蠕虫。在这项工作中，我们提出了一种简单可行的微流控芯片，以实现线虫的同时分选。通过分级的微过滤器可以选择不同的尺寸。微型设备由PDMS-琼脂糖混合层组成，该层由5个几何优化的方柱阵列组成，作为用于分离不同大小蠕虫的微过滤器。同时应用流体流动和电场来驱动蠕虫快速定向地通过微过滤器，从而提高了分选效率和准确性。此外，通过将PDMS层滑到凹槽顶部，可以轻松地从琼脂糖层的4个凹槽中收集分类的蠕虫。通过这种分类策略，我们证明了同时分类不同大小的秀丽隐杆线虫的可行性。效率高，准确性高（> 95％），每分钟可处理数百个蠕虫。因此，微型设备可能是需要大量阶段同步蠕虫的秀丽隐杆线虫检测的有前途的工具。它对于秀丽隐杆线虫的基于体型的突变体筛选和出租车反应研究也可能是有用的。