High-performance multicapillary gas separation columns with MPG stationary phases

This paper reports the development of microfabricated multicapillary columns (μMCC) with self-assembled stationary phases for high-performance gas separation. The fabrication process merging a double-doped MEMS fabrication process and nanotechnology provides highly reproducible and conformal gold deposition inside 250μm-deep, 30μm-wide, 25cm-long μMCC with 16 channels. This technique also affords excellent bonding and coating yields (~95%). To evaluate chromatographic performance, μMCCs were functionalized by self-assembly of octadecanethiol (C₁₈H₃₇SH) to form monolayer-protected-gold (MPG) surface. These columns demonstrated 7300 plates/m, the highest reported on μMCCs, and separated a complex gas mixture containing compounds with wide range of boiling points.