Hydrodynamic and electrodynamic flow mixing in a novel total glass chip mixer with streamline herringbone pattern

Abstract

Mixing is a precondition for efficient chemical and biochemical reactions, especially in limited time and space, such as in a laboratory on a chip system under various flow conditions. In this work, a novel method of preparing a total glass chip mixer with a streamline herringbone structure is presented. The main mixing channel and the embedded herringbone pattern were simultaneously generated by one-step photolithographic exposure and one-step wet etching of glass substrate. The mixing performance under typical pressure flow as well as high DC voltage-activated migration conditions, thanks to the charged and stable surface nature of the glass substrate, was investigated experimentally by microscope fluorescent imaging using charged and neutral fluorescence molecular probes, respectively. The passive chip mixer was effective for both hydrodynamic and electrodynamics migration conditions, and over 90 % mixing was achieve in 20 mm in the mixing channel of only 300 nL. The applicability of the chip was demonstrated by a chemiluminescence reaction with enhanced signal and detection power. The chemical resistive surface, integrity, transparency, and high mixing efficiency of this passive chip mixer are advantageous for microanalytical systems of various flow conditions, especially miniaturized chromatography or electrophoresis systems.