Water affinity of LIGA polymers for microfluidic lab-on-chips
In the work the water affinity and limiting wetting angles of polymer surfaces, which are used for structuring of a microfluidic lab on a chip by LIGA technology – X-ray lithography, galvanoplastics and molding of polymer device, have been studied. The technique of the determinations of the limiting values includes the geometrical measurements of calibrated liquid drops by means of an optical microscope. The chemical atomic contents of the polymer surface layers were characterized by the method of the X-ray fluorescence which is induced by an e-beam of the electron scanning microscope. The peculiarities of wetting in micro channels in the organic glass, optical silicone, SU-8 polymer, fluorine plastic and Kapton are discussed in order to design a microfluidic module for a system analysis of an interaction of reagents in biochemical water solutions.