Scherr Thomas F, Ryskoski Hayley B, Doyle Andrew B, Haselton Frederick R
Department of Biomedical Engineering, Vanderbilt University , Nashville, Tennessee 37235, USA.
Biomicrofluidics. 2016 Apr 11;10(2):024118. doi: 10.1063/1.4946014. eCollection 2016 Mar.
Magnetic beads are a popular method for concentrating biomolecules from solution and have been more recently used in multistep pre-arrayed microfluidic cartridges. Typical processing strategies rely on a single magnet, resulting in a tight cluster of beads and requiring long incubation times to achieve high capture efficiencies, especially in highly viscous patient samples. This report describes a two-magnet strategy to improve the interaction of the bead surface with the surrounding fluid inside of a pre-arrayed, self-contained assay-in-a-tube. In the two-magnet system, target biomarker capture occurs at a rate three times faster than the single-magnet system. In clinically relevant biomatrices, we find a 2.5-fold improvement in biomarker capture at lower sample viscosities with the two-magnet system. In addition, we observe a 20% increase in the amount of protein captured at high viscosity for the two-magnet configuration relative to the single magnet approach. The two-magnet approach offers a means to achieve higher biomolecule extraction yields and shorter assay times in magnetic capture assays and in self-contained processor designs.
磁珠是一种从溶液中富集生物分子的常用方法，最近已被应用于多步预排列的微流控芯片中。典型的处理策略依赖于单个磁铁，这会导致磁珠紧密聚集，并且需要较长的孵育时间才能实现高捕获效率，尤其是在高粘度的患者样本中。本报告描述了一种双磁体策略，以改善预排列的独立式管内检测中磁珠表面与周围流体的相互作用。在双磁体系统中，目标生物标志物的捕获速度比单磁体系统快三倍。在临床相关的生物基质中，我们发现双磁体系统在较低样品粘度下生物标志物捕获率提高了2.5倍。此外，相对于单磁体方法，我们观察到双磁体配置在高粘度下捕获的蛋白质量增加了20%。双磁体方法为在磁捕获检测和独立式处理器设计中实现更高的生物分子提取产量和更短的检测时间提供了一种手段。
