Title: | Polymer-coated micro-optofluidic ring resonator detector for a comprehensive two-dimensional gas chromatographic microsystem: muGC xmuGC-muOFRR |
Author(s): | Collin WR; Scholten KW; Fan X; Paul D; Kurabayashi K; Zellers ET; |
Address: | "Department of Chemistry, University of Michigan, Ann Arbor, MI, 48109-1055, USA. ezellers@umich.edu" |
ISSN/ISBN: | 1364-5528 (Electronic) 0003-2654 (Linking) |
Abstract: | "We describe first results from a micro-analytical subsystem that integrates a detector comprising a polymer-coated micro-optofluidic ring resonator (muOFRR) chip with a microfabricated separation module capable of performing thermally modulated comprehensive two-dimensional gas chromatographic separations (muGC xmuGC) of volatile organic compound (VOC) mixtures. The 2 x 2 cm muOFRR chip consists of a hollow, contoured SiO(x) cylinder (250 mum i.d.; 1.2 mum wall thickness) grown from a Si substrate, and integrated optical and fluidic interconnection features. By coupling to a 1550 nm tunable laser and photodetector via an optical fiber taper, whispering gallery mode (WGM) resonances were generated within the muOFRR wall, and shifts in the WGM wavelength caused by transient sorption of eluting vapors into the PDMS film lining the muOFRR cylinder were monitored. Isothermal separations of a simple alkane mixture using a PDMS coated 1st-dimension ((1)D) mucolumn and an OV-215-coated 2nd-dimension ((2)D) mucolumn confirmed that efficient muGC xmuGC-muOFRR analyses could be performed and that responses were dominated by film-swelling. Subsequent tests with more diverse VOC mixtures demonstrated that the modulated peak width and the VOC sensitivity were inversely proportional to the vapor pressure of the analyte. Modulated peaks as narrow as 120 ms and limits of detection in the low-ng range were achieved. Structured contour plots generated with the muOFRR and a reference FID were comparable" |
Keywords: | "Alkanes/analysis/chemistry Chromatography, Gas/*instrumentation *Lab-On-A-Chip Devices *Optical Devices Polymers/*chemistry;" |
Notes: | "MedlineCollin, William R Scholten, Kee W Fan, Xudong Paul, Dibyadeep Kurabayashi, Katsuo Zellers, Edward T eng Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. England 2015/11/21 Analyst. 2016 Jan 7; 141(1):261-9. doi: 10.1039/c5an01570g. Epub 2015 Nov 20" |