2019 年 32 巻 1 号 p. 107-113
The poly(dimethylsiloxane) (PDMS)-based microchannel of a microcapillary chip is attractive for characterization of nanoparticles (NPs). The surface potential of PDMS is negative in nature, and in the presence of charged NPs, an interaction exists between the NPs and microchannel surface. In this study, the adsorption phenomena of nanoliposomes in the microchannel was investigated using a microfluidic chip designed for the autonomous compensation of hydrostatic pressure flow in the presence of neutral or cationic polymer coating. The Brownian motion of the nanoliposomes in the region of interest was stably observed without any fluid flow. The adsorption phenomena of the nanoliposomes on the microchannel surface arose from hydrophobic and electrostatic interaction, and can be attenuated based on electrostatic repulsion and the excluded volume effect.