The microfluidic chip fabricated by Hot Embossing Lithography for single- microsphere test

Polymer-based microfluidic chips are becoming increasingly important for biological applications and fluidic control. In this article, we report and demonstrate a novel fabrication process of a Poly(dimethylsiloxane) (PDMS) device by casting fabrication technology, sometimes called soft lithography, which involves creation of positive mold containing the sub-20μm width microchannel microstructures that were fabricated by Hot Embossing Lithography(HEL)which is a low cost, fast method for the parallel replication methods. The microspheres with the diameter of 13~15μm were injected directly into the inlet reservoirs and passed through one by one in the microchannel by the external pumps which is very useful for the detection and counting of microspheres.