Fabrication and Preliminary Results for LiGA Fabricated Nickel Micro Gas Chromatograph Columns

Abstract

High aspect ratio nickel microfluidic columns were fabricated using the LiGA technique. The 2-m-long 50-mum-wide high aspect ratio columns will be the separation component of a handheld gas chromatograph device for detecting semivolatile and volatile compounds. As a first step, 600-mum-deep electrodeposited nickel columns were fabricated. The serpentine columns were sealed and pressure-flow rate characteristics compared with the theoretical values. The response of the sealed columns was studied by running methane gas plugs through uncoated columns with a flame ionization detector at the exit. Negligible flow-induced dispersion was observed in the sealed metal columns. Unretained peak widths of ~15 ms were measured, and the experimental pressure and flow rate distributions matched those predicted by established analytical models within plusmn2.5%. Columns were coated with OV-1 stationary phase using static coating methods. A mixture of four hydrocarbons C <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sub> , C <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">8</sub> , C <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">10</sub> , and C <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">12</sub> was separated in a coated 50 mum by 600 mum by 0.5 m column in less than 2 s at 70 degC