Liu Ping, Liu Hangrui, Semenec Lucie, Yuan Dan, Yan Sheng, Cain Amy K, Li Ming
Suqian University, Suqian, 223800 China.
School of Engineering, Macquarie University, Sydney, NSW 2109 Australia.
Microsyst Nanoeng. 2022 Jan 19;8:7. doi: 10.1038/s41378-021-00333-3. eCollection 2022.
In this study, we demonstrated the label-free continuous separation and enrichment of populations based on length using viscoelastic microfluidics. , a gram-positive, rod-shaped bacterium, has been widely used as a model organism and an industrial workhorse. can be arranged in different morphological forms, such as single rods, chains, and clumps, which reflect differences in cell types, phases of growth, genetic variation, and changing environmental factors. The ability to prepare populations with a uniform length is important for basic biological studies and efficient industrial applications. Here, we systematically investigated how flow rate ratio, poly(ethylene oxide) (PEO) concentration, and channel length affected the length-based separation of cells. The lateral positions of cells with varying morphologies in a straight rectangular microchannel were found to be dependent on cell length under the co-flow of viscoelastic and Newtonian fluids. Finally, we evaluated the ability of the viscoelastic microfluidic device to separate the two groups of cells by length (i.e., 1-5 μm and >5 μm) in terms of extraction purity (EP), extraction yield (EY), and enrichment factor (EF) and confirmed that the device could separate heterogeneous populations of bacteria using elasto-inertial effects.
在本研究中，我们展示了使用粘弹性微流体技术基于长度对群体进行无标记连续分离和富集。枯草芽孢杆菌是一种革兰氏阳性杆状细菌，已被广泛用作模式生物和工业主力菌株。枯草芽孢杆菌可呈现不同的形态形式，如单杆、链状和团块状，这反映了细胞类型、生长阶段、遗传变异和环境因素变化的差异。制备具有均匀长度的枯草芽孢杆菌群体的能力对于基础生物学研究和高效工业应用至关重要。在此，我们系统地研究了流速比、聚环氧乙烷（PEO）浓度和通道长度如何影响枯草芽孢杆菌细胞基于长度的分离。发现在粘弹性流体和牛顿流体的共流作用下，具有不同形态的枯草芽孢杆菌细胞在直矩形微通道中的横向位置取决于细胞长度。最后，我们从提取纯度（EP）、提取产率（EY）和富集因子（EF）方面评估了粘弹性微流体装置按长度分离两组枯草芽孢杆菌细胞（即1 - 5μm和>5μm）的能力，并证实该装置可利用弹性惯性效应分离细菌异质群体。
