Fast and versatile fabrication of PMMA microchip electrophoretic devices by laser engraving

Abstract

This paper describes the effects of different modes and engraving parameters on the dimensions of microfluidic structures produced in PMMA using laser engraving. The engraving modes included raster and vector while the explored engraving parameters included power, speed, frequency, resolution, line-width and number of passes. Under the optimum conditions, the technique was applied to produce channels suitable for CE separations. Taking advantage of the possibility to cut-through the substrates, the laser was also used to define solution reservoirs (buffer, sample, and waste) and a PDMS-based decoupler. The final device was used to perform the analysis of a model mixture of phenolic compounds within 200 s with baseline resolution.

Modification of microfluidic paper-based devices with silica nanoparticles

“…Details about the system and its capabilities can be found elsewhere. 41 This system was connected to an air filter (model AD350, BOFA; Staunton, IL), equipped with a HEPA / activated aluminum / potassium permanganate and an activated carbon panel to remove fumes from the engraver. To minimize the risk of ignition of the paper during the cutting process, a stream of N 2 was impinged on the engraving point.…”

Fast production of microfluidic devices by CO2 laser engraving of wax‐coated glass slides

“…Aiming to overcome these disadvantages, polymeric materials such as PDMS , polycarbonate , polyester‐toner , and PMMA have been extensively used. In general, polymeric microchips have been produced by soft lithography , hot embossing , direct‐printing process and laser ablation resulting in faster production methodologies at lower costs. Engraving of glass substrates by femtosecond laser can eliminate the use of cleanroom environments as well as the need for masks and molds during the fabrication, but standard instruments are expensive and not commonly found in chemical laboratories .…”

“…Engraving of glass substrates by femtosecond laser can eliminate the use of cleanroom environments as well as the need for masks and molds during the fabrication, but standard instruments are expensive and not commonly found in chemical laboratories . On the contrary, standard‐grade CO 2 laser engraving has proven suitable for prototyping microfluidic devices in a variety of materials, including PDMS , PMMA , and paper . Due to the low thermal conductivity and significant coefficient of thermal expansion of common soda lime glass, fabrication of microfluidic devices by laser engraving often leads to cracking and/or a poor channel quality.…”

“… demonstrated the possibility of engraving low thermal expansion glasses like quartz, borofloat and Pyrex. The channels obtained featured a narrow Gaussian shape, typically obtained by CO 2 ablation of polymers under high power . Using a layer of water on the surface of the glass, small holes (100–200 μm of diameter) can be produced in Pyrex .…”

“…The raster mode is typically used for marking and/or making steps in the materials and can reach a top speed of 2200 mm/s while the vector mode, normally used to cut through substrates, can reach a top speed of 90 mm/s. More information about the system can be found in a recent publication from our group .…”