▎ 摘　　要

We fabricated a microfluidic channel with a graphene oxide (GNO)-doped polydimethylsiloxane photothermal heater for thermophoretically shifting particles. Under 808 nm near infrared (NIR) irradiation, GNO doped in one side of the channel walls would be heated through the photothermal effect, which would create a temperature gradient in the channel and drive particles shifting toward the cold side. By controlling NIR intensity and irradiation area, the temperature distribution in the channel can be conveniently adjusted, which can be used to separate micro- and nano-particles by changing the shifting distance of the particles. Meanwhile, as GNO was directly doped in channel walls, this method can fit channels with complex shapes well, which is useful for improving the separation efficiency by adding complex structures in channels. The study provides a controllable and convenient heating method for microfluidic thermophoresis experiments.