Systematic evolution of ligands by exponential enrichment (SELEX) offers a powerful method to isolate affinity oligonucleotides known as aptamers, which can then be used in a wide range of applications from drug delivery to biosensing. However, conventional SELEX methods rely on labor intensive and time consuming benchtop operations. A simplified microfluidic approach is presented which allows integration of the affinity selection and amplification stages of SELEX for the isolation of target-binding oligonucleotides by combining bead-based biochemical reactions with free solution electrokinetic oligonucleotide transfer. Free solution electrokinetics allows coupling of affinity selection and amplification for closed loop oligonucleotide enrichment without the need for offline processes, flow handling components or gel components, while bead based selection and amplification allow efficient manipulation of reagents and reaction products thereby realizing on-chip loop closure and integration of the entire SELEX process. Thus the approach is capable of multi-round enrichment of oligonucleotides using simple transfer processes while maintaining a high level of device integration, as demonstrated by the isolation of an aptamer pool against a protein target (IgA) with significantly higher binding affinity than the starting library in approximately 4 hours of processing time.

中文翻译：

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使用自由溶液电动力学的集成微流体 Selex

通过指数富集 (SELEX) 对配体进行系统进化提供了一种强大的方法来分离称为适体的亲和寡核苷酸，然后可以将其用于从药物递送到生物传感的广泛应用。然而，传统的 SELEX 方法依赖于劳动密集型和耗时的台式操作。提出了一种简化的微流体方法，通过将基于珠的生化反应与自由溶液电动寡核苷酸转移相结合，可以整合 SELEX 的亲和选择和放大阶段，以分离目标结合寡核苷酸。自由溶液电动力学允许结合亲和选择和扩增闭环寡核苷酸富集，而无需离线过程、流动处理组件或凝胶组件，而基于珠子的选择和扩增允许有效操纵试剂和反应产物，从而实现整个 SELEX 过程的片上闭环和集成。因此，该方法能够使用简单的转移过程对寡核苷酸进行多轮富集，同时保持高水平的设备集成，如针对蛋白质靶标 (IgA) 的适体池的分离所证明的，其结合亲和力明显高于起始文库在大约 4 小时的处理时间内。