打开DNA双链的物理新方法——激光微流法

Double-strand DNA melted by laser micro-flow method

文章报道了一种打开DNA双链的物理方法——激光微流法.DNA双链分子被固定在石英片的表面,在一定强度的激光衰逝波和微流振荡共同作用下,DNA双链间的氢键被迅速打开.利用全内反射单分子荧光共振能量转移技术,可以观察到激光微流法打开单个DNA的动力学过程.通过对激光进行控制,可以准确地打开连接在石英表面特定位置的DNA双链.DNA分子打开的比例与激光功率的关系表明微流产生的机械能与激光光能在DNA双链打开过程中缺一不可.

We present a physical method,based on laser micro-flow,to melt double-strands of DNA.When DNA molecules are immobilized on a quartz surface,the hydrogen bonds between complementary strands can be broken rapidly under the control of a laser evanescent wave and micro-flow oscillation.Employing a single-molecule fluorescence resonance energy transfertechnique,the dynamics of DNA melting is studied at the single-molecule level.When the DNA is in a special position,it can be melted by a laser beam focused to a pinpoint.It is shown that the percentage of melted DNA increases proportionally with laser power.Furthermore,we can determine the contribution of the micro-flow mechanics in the melting process.