BIOS/Lab-on-chip group, MESA+ Institute for Nanotechnology, University of Twente, Enschede, The Netherlands.
Lab Chip. 2013 May 21;13(10):1955-62. doi: 10.1039/c3lc41100a. Epub 2013 Apr 2.
The kinetic activity of individual enzyme molecules was determined in aqueous droplets generated in a nano- and microfluidic device. To avoid high background noise, the enzyme and substrate solution was confined into femtoliter carriers, achieving high product concentrations from single-molecule encapsulation. The tiny droplets (φ ~ 2.5-3 μm) generated from this fluidic system were highly monodisperse, beneficial for an analysis of single enzyme activity. The method presented here allows to follow large numbers of individual droplets over time. The instrumental requirements are furthermore modest, since the small droplet size allows to use of standard microscope and standard Pyrex glass chips as well as the use of relatively high enzyme concentrations (nM range) for single molecule encapsulation.
在纳米和微流控装置中生成的水相液滴中，测定了单个酶分子的动力学活性。为避免高背景噪声，将酶和底物溶液限制在皮升载体中，通过单分子包封实现了高产物浓度。从该流体系统产生的微小液滴（φ~2.5-3μm）高度单分散，有利于单个酶活性的分析。本文介绍的方法允许长时间跟踪大量的单个液滴。此外，仪器要求也不苛刻，因为小液滴尺寸允许使用标准显微镜和标准派热克斯玻璃芯片，并且可以使用相对较高的酶浓度（纳摩尔范围）进行单分子包封。
