Abstract
In biological, chemical, and medical analyses, the mechanism of particle motion at near-surface is greatly attracted attention for prediction of chemical characteristics such as reaction time and efficiency in micro chip. In this paper, we developed observational method of 3-D particle motion at near-surface used evanescent wave and PTV. A precise measurement was developed for calibration of position of particle in direction of depth. And we evaluated Brownian motion and concentration distribution of polyethylene latex particle (diameter 100nm) motion at near-surface in micro-channel. The results show Brownian motion is hindered as particle close to wall. In addition, the concentration is the lowest at near-surface and shows the largest value at specific location from wall. The location is consistent with theoretical particle-wall minimum potential location.
