Amplification reactions coupled with electrophoresis or real-time fluorescence system have been successfully used for the analysis of nucleic acid. However, complex procedures or expensive instruments greatly limit their application in low-resource settings. To address these shortcomings, we fabricated a universal and simple detection platform by integrating strand exchange amplification (SEA) with lateral flow assay (LFA) strip. SEA is a simple isothermal amplification reaction, only requires a pair of primers and one DNA polymerase, above all, its short amplicons are easy to migrate on the strip. LFA strip was proved to be stable for months without large signal deviations and result could be easy to read by naked eyes, which makes it an appropriate option for field-based analysis. Our proposed SEA-LFA strip could reliably detect as few as 0.05 nM pork DNA and 0.07 nM duck DNA by the naked eye, its analytical performance is comparable with laboratory-based real-time fluorescence test. Furthermore, this proof-of-concept method could be applied to detect a wide variety of nucleic acid by focusing on primer design rather than on the development of a wholly new analysis platform. We believe that this simple visualization system has great potential as a preliminary test tool in resource-limited areas.

结合电泳或实时荧光系统的扩增反应已成功用于核酸分析。但是，复杂的过程或昂贵的仪器极大地限制了它们在资源贫乏地区的应用。为了解决这些缺点，我们通过将链交换扩增（SEA）与侧向流动测定（LFA）试纸相结合，制造了一个通用且简单的检测平台。SEA是一种简单的等温扩增反应，仅需一对引物和一个DNA聚合酶，最重要的是，其短扩增子易于在试纸上迁移。事实证明，LFA试纸可在数月之内保持稳定，并且信号偏差不大，并且肉眼易于读取结果，这使其成为基于现场分析的合适选择。我们提出的SEA-LFA试纸条可以可靠地检测到0。肉眼观察到05 nM猪肉DNA和0.07 nM鸭DNA，其分析性能可与基于实验室的实时荧光测试相媲美。此外，这种概念验证方法可通过专注于引物设计而不是开发全新的分析平台来应用于检测多种核酸。我们认为，这种简单的可视化系统在资源有限的地区作为初步测试工具具有巨大的潜力。