Laser-treated hydrophobic paper: an inexpensive microfluidic platform.
We report a method for fabricating inexpensive microfluidic platforms on paper using laser treatment. Any paper with a hydrophobic surface coating (e.g., parchment paper, wax paper, palette paper) can be used for this purpose. We were able to selectively modify the surface structure and property (hydrophobic to hydrophilic) of several such papers using a CO(2) laser. We created patterns down to a minimum feature size of 62±1 µm. The modified surface exhibited a highly porous structure which helped to trap/localize chemical and biological aqueous reagents for analysis. The treated surfaces were stable over time and were used to self-assemble arrays of aqueous droplets. Furthermore, we selectively deposited silica microparticles on patterned areas to allow lateral diffusion from one end of a channel to the other. Finally, we demonstrated the applicability of this platform to perform chemical reactions using luminol-based hemoglobin detection.
School of Mechanical Engineering, Purdue University, West Lafayette, IN 47907, USA.
Girish
G
Chitnis
Zhenwen
Z
Ding
Chun-Li
CL
Chang
Cagri A
CA
Savran
Babak
B
Ziaie
D006454:Hemoglobins / Q000032:analysis; D057927:Hydrophobic and Hydrophilic Interactions; D007834:Lasers; D008165:Luminol / Q000737:chemistry; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation / Q000379:methods*; D010209:Paper; D016062:Porosity; D012822:Silicon Dioxide / Q000737:chemistry
D006454:Hemoglobins; D008165:Luminol; D012822:Silicon Dioxide