Optimizing microfabricated liquid planar waveguides for microfluidic lab-on-chip flow cytometry systems

摘要

A versatile method for integrating liquid waveguides into PDMS microfluidic flow-cytometer chips is presented. By using a one-step direct replication, PDMS chips are produced with both liquid and waveguide channels. Filling the waveguide channels with high refractive index media, a simple waveguide is created using the PDMS of the chip itself as cladding. Optical fibers are used to couple laser light and fluorescence into, and out of the chip. Experimental results and ray-tracing simulations show that the light intensity at distances above 5 mm from the source is more than four times higher when using gelatin or DMSO as compared to channels containing only air.