Laser patterning for paper-based fluidics

Paper-based microfluidics is a rapidly progressing inter-disciplinary technology driven by the need for low-cost alternatives to conventional point-of-care diagnostic tools. For transport of reagents/analytes, such devices often consist of interconnected hydrophilic fluid-flow channels that are demarcated by hydrophobic barrier walls that extend through the thickness of the paper. Here, we present a laser-based fabrication procedure that uses photo-polymerisation of a negative hydrophobic photoresist in order to produce the required fluidic channels in paper. Analysis showed that the structures directed the flow of water and hence the technique is suited for fabrication of microfluidic devices