Radial analyte concentration in microfluidics with an integrated planar nanoporous film

• Main Author: Scarff, Brent
• Other Authors: Sinton, David A.
• Language: English; en
• Published: 2010
• Subjects: Microfluidics; Nanofluidics; UVic Subject Index::Sciences and Engineering::Engineering::Mechanical engineering
• Online Access: http://hdl.handle.net/1828/2978

This work revolves around the development of microfluidic technology for use in biomedical diagnostics with a specific focus on analyte concentration. At the reduced scale inherent with microfluidic technologies the sensing of target species can be difficult since the sample volume is reduced to nanolitres leading to low amounts of target species. This necessitates the need to preconcentrate samples prior to the sensing step. The exclusion-enrichment phenomenon associated with concentration polarization has been used within microfluidic platforms for the purpose of analyte concentration though methods have all been inherently 1-D, axial configurations. Within this work a novel radial concentration strategy based on a single microfluidic layer on a uniform nanoporous film is presented. The active nanostructured region is defined by the microfluidics, providing flexibility and opening opportunities beyond the single-channel axial configurations to date. Radial geometries have not been previously shown operating as CP based concentration devices, though the unique geometry offers enhanced flux at the perimeter and the capability to focus samples down to small central regions. This focusing ability allows the concentration to take place on a separate layer and does not compete for space with other analysis fluidics. This radial configuration is numerically modeled and experimentally demonstrated.