A liquid molding method for the fabrication of microfluidic devices based on a drop-on-demand generation of patterned substrates

Microfluidic device is an important analysis platform and has been widely used in micro total analysis systems for various applications. This article presented a simple approach for the fabrication of microfluidic device based on a drop-on-demand printing technology and liquid molding process. The patterned substrates with hydrophobic/hydrophilic intersecting regions were formed by directly printing the melted wax on the substrates and treated with hydrophobic solution. Liquid molds with the smallest width of 70 A mu m were anchored on the hydrophilic region through a dip-coating method and the height was improved by printing more liquid on the molds. The channel surface was smooth as the arithmetical mean deviation of the profile Ra with the 95 A mu m(2) x 325 A mu m(2) area at the bottom was 125.1 nm and the aspect ratio of the channel could increased up to 0.28. The droplet generation at the T-cross of the channel was realized with water and mineral oil and the method supplied a low-cost and simple method for the fabrication of microfluidic devices.