FLASH: A rapid method for prototyping paper-based microfluidic devices

Department of Chemistry & Chemical Biology, Harvard University, Cambridge, MA 02138, USA.
Lab on a Chip (Impact Factor: 6.12). 01/2009; 8(12):2146-50. DOI: 10.1039/b811135a
Source: PubMed

ABSTRACT This article describes FLASH (Fast Lithographic Activation of Sheets), a rapid method for laboratory prototyping of microfluidic devices in paper. Paper-based microfluidic devices are emerging as a new technology for applications in diagnostics for the developing world, where low cost and simplicity are essential. FLASH is based on photolithography, but requires only a UV lamp and a hotplate; no clean-room or special facilities are required (FLASH patterning can even be performed in sunlight if a UV lamp and hotplate are unavailable). The method provides channels in paper with dimensions as small as 200 microm in width and 70 microm in height; the height is defined by the thickness of the paper. Photomasks for patterning paper-based microfluidic devices can be printed using an ink-jet printer or photocopier, or drawn by hand using a waterproof black pen. FLASH provides a straightforward method for prototyping paper-based microfluidic devices in regions where the technological support for conventional photolithography is not available.

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Available from: Scott T Phillips, Mar 11, 2015
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    • "fabricated in controlled environments (cleanrooms) with a standard subtractive lithographic process, thus producing chemicals waste and costly products. Nowadays, several techniques are proposed: laser etched fluidics, craft cut fluidics and wax impregnated capillary action fluidics on paper; all of these methods can be implemented outside of a cleanroom and in a simple way [5]–[7]. However, one issue consists still of integration of the electronic part with the microfluidic, keeping the fabrication cost low, given the fact that to pattern interface and sensing microelectronics onto the chip requires, by now, the use of standard etching technology. "
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    IEEE Sensors Journal 06/2015; 15(6):3156-3163. DOI:10.1109/JSEN.2014.2374874 · 1.76 Impact Factor
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    • "In addition, in the proposed nonwoven based sensor, during patterning the isotropic structure of the nonwoven substrate provides an even spreading of photoresist polymer in x,y-plane as well as z direction through the entire fabric thickness which is critical for creating a welldemarcated hydrophobic-hydrophilic contrast of the pattern. The two-dimensional orientation of fibers in x,y-plane of a sheet of paper has been reported as a constraint since the liquid polymer tends to spread in the x,y-plane of paper rather than in the zdirection leading to blurring of the patterns [12] [31] [33] [34]. A good hydrophobic-hydrophilic contrast of the pattern is also required to avoid the leakage of the fluid consisting of the analyte through the channels and spreading through the device. "
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    Sensors and Actuators B Chemical 03/2015; 208:475-484. DOI:10.1016/j.snb.2014.11.042 · 4.10 Impact Factor
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    • "Many paper-based analytical devices are used as low-cost substitutes for medical point-of-care diagnostics due to the necessity of fast, reliable and affordable diagnostic tools in poverty-stricken developing countries [10]. Lately, Whitesides' group has developed techniques for creating microfluidic devices from patterned paper and demonstrated the use of paper-based microfluidic devices for colorimetric detection of glucose and protein in artificial urine [11] [12] [13] [14]. Glucose oxidase (GOx) is widely used in practical applications for quick and precise glucose analysis. "
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    ABSTRACT: This paper describes a simple inexpensive paper-based amperometric glucose biosensor developed based on Prussian Blue (PB)-modified screen-printed carbon electrodes (SPCEs). The use of cellulose paper proved to be a simple, "ideal" and green biocompatible immobilization matrix for glucose oxidase (G0x) as it was successfully embedded within the fibre matrix of paper via physical adsorption. The glucose biosensor allowed a small amount (0.5 mu L) of sample solution for glucose analysis. The biosensor had a linear calibration range between 0.25 mM and 2.00 (R-2= 0.987) and a detection limit of 0.01 mM glucose (S/N = 3). Interference study of selected potential interfering compounds on the biosensor response was investigated. Its analytical performance was demonstrated in the analysis of selected commercial glucose beverages. Despite the simplicity of the immobilization method, the biosensor retained ca. 72% of its activity after a storage period of 45 days.
    Sensors and Actuators B Chemical 12/2014; 204:414–420. DOI:10.1016/j.snb.2014.07.103 · 4.10 Impact Factor
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