Hypersensitive closed tube-type colorimetric loop-mediated isothermal amplification method utilizing carboxyl-modified gold nanometer particles

Abstract

The invention relates to a hypersensitive closed tube-type colorimetric loop-mediated isothermal amplification method utilizing carboxyl-modified gold nanometer particles. The method comprises that through combination of LAMP and a MUA-AuNP novel detection mechanism utilizing Mg<2+> and P2O7<4-> to control a color change, an AuNP-based colorimetric operation-closed tube type isothermal amplication combined nucleic acid detection platform is built and realizes visual detection of 200 copies of target DNA sequences. A color is controlled by magnesium ion template aggregation, and in the presence of a target, LAMP reaction by-product pyrophosphoric acid ions cause particle depolymerization. The platform has the advantages of high sensitivity, no residual pollutes and low cost. 本发明涉及使用羧基修饰的金纳米颗粒的超灵敏闭管式比色环介导等温扩增法。具体而言，本发明将MUA-AuNP的由Mg2+和P2O74-控制的颜色变化的新检测机制与LAMP结合，首次建立并结合了基于AuNP的比色和闭管式等温扩增的核酸检测平台，使可以用肉眼检测少至200个拷贝的靶DNA序列。由镁离子模板聚集控制颜色，并且在存在靶时，LAMP反应的副产物焦磷酸离子导致颗粒解聚。该平台具备高灵敏度、无残留污染、低成本等优点。