Department of Physics, Virginia Commonwealth University, Richmond, Virginia 23284, USA.
J Am Chem Soc. 2013 Feb 27;135(8):3087-94. doi: 10.1021/ja309892e. Epub 2013 Feb 14.
The ability to perturb large ensembles of molecules from equilibrium led to major advances in understanding reaction mechanisms in chemistry and biology. Here, we demonstrate the ability to control, measure, and make use of rapid temperature changes in fluid volumes that are commensurate with the size of single molecules. The method is based on attaching gold nanoparticles to a single nanometer-scale pore formed by a protein ion channel. Visible laser light incident on the nanoparticles causes a rapid and large increase of the adjacent solution temperature, which is estimated from the change in the nanopore ionic conductance. The temperature shift also affects the ability of individual molecules to enter into and interact with the nanopore. This technique could significantly improve sensor systems and force measurements based on single nanopores, thereby enabling a method for single molecule thermodynamics and kinetics.
从平衡态中扰动大量分子的能力，使得在化学和生物学中对反应机制的理解取得了重大进展。在这里，我们展示了控制、测量和利用与单个分子大小相当的流体体积中快速温度变化的能力。该方法基于将金纳米粒子附着到由蛋白质离子通道形成的单个纳米尺度孔上。可见光激光照射到纳米粒子上会导致相邻溶液温度的快速大幅升高，这可以根据纳米孔离子电导率的变化来估算。温度变化也会影响单个分子进入和与纳米孔相互作用的能力。该技术可以显著改善基于单个纳米孔的传感器系统和力测量，从而为单分子热力学和动力学提供一种方法。
