Laser-treated Parchment Paper: An Inexpensive Microfluidic Platform
- PDF / 2,495,014 Bytes
- 6 Pages / 612 x 792 pts (letter) Page_size
- 76 Downloads / 190 Views
Laser-treated Parchment Paper: An Inexpensive Microfluidic Platform Girish Chitnis1,5, Zhenwen Ding2,5, Chun-Li Chang3,5, Cagri A. Savran1,3,4,5 and Babak Ziaie3,4,5 1
School of Mechanical Engineering, Purdue University, West Lafayette, IN 47907 Department of Physics, Purdue University, West Lafayette, IN 47907 3 School of Electrical and Computer Engineering, Purdue University, West Lafayette, IN 47907 4 Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907 5 Birck Nanotechnology Center, Purdue University, West Lafayette, IN 47907 2
ABSTRACT In this paper, we report on a method for fabricating an inexpensive microfluidic platform on parchment paper. Parchment paper was selected for this purpose due to its wide availability for culinary applications and hydrophobic silicone-based surface coating. We were able to selectively modify the surface structure and property (hydrophobic to hydrophilic) using a CO2 laser. The modified surface has highly-porous structure which helps to trap chemical and biological reagents for analysis. The treated surface is stable over time and can be used for aqueous droplet assembly. Finally, we demonstrated the applicability of this platform for performing chemical reaction using luminol-based hemoglobin detection. INTRODUCTION Chemically impregnated paper strips, such as litmus paper, have been popular for long time. Commercially available diagnostic tests, such as diabetes and pregnancy test, are also paper strip based assays. Microfluidic structures on paper have potential to enhance such paper based detection techniques. Patterning paper to create hydrophilic-hydrophobic structures for microfluidic platforms used in medical diagnostic tests has been pioneered by Whiteside and his co-workers [1]. In their original work, they used SU8-soaked chromatography paper which was subsequently patterned by lithography to create microfluidic channels for medical diagnostics [14]. It attracted a considerable attention due to its simplicity, low-cost, disposability, and portability [5-6]. In later works, they also explored plotting hydrophilic/hydrophobic patterns on filter paper using hexanes-dissolved PDMS [7]. Most recently, wax printing has been used to define hydrophobic barriers and fabricate millimeter scale microfluidic channels on paper [8, 9]. All of the abovementioned methods create hydrophilic microfluidics on paper by depositing hydrophobic polymers. In this paper, we present an alternative method for fabricating inexpensive microfluidic platforms. Parchment paper (Reynolds) was selected for this purpose due to its wide availability for culinary applications and hydrophobic silicone-based surface coating. We employed selective surface modification using a CO2 laser to create hydrophilic patterns on parchment paper. Laser modification can alter the wettability of the engineering materials by causing structural and chemical changes to the surface [10]. In contrast with the methods described by Whiteside’s group which start with a plain paper and are predom
Data Loading...
