title: A digital microfluidic interface between solid-phase microextraction and liquid chromatography-mass spectrometry.
abstract: We introduce a method to couple solid-phase microextraction (SPME) with HPLC-MS using digital microfluidics (DMF). In the new system, SPME fibers are used to extract analytes from complex sample solutions, after which the analytes are desorbed into solvent droplets in a DMF device. The open geometry of DMF allows straightforward insertion of SPME fibers without requiring a complicated interface, and automated droplet manipulation enables multiplexed processing of the fibers. In contrast to other multiplexed SPME elution interfaces, the low volumes inherent to DMF allow for pre-concentration of analytes prior to analysis. The new SPME-DMF-HPLC-MS method was applied to the quantification of pg/mL-level free steroid hormones in urine. We propose that this new method will be useful for a wide range of applications requiring cleanup and pre-concentration with convenient coupling to high-performance analytical techniques.
authors.affiliation: Department of Chemistry, University of Toronto, 80 St George St., Toronto, ON M5S 3H6, Canada; Donnelly Centre for Cellular and Biomolecular Research, 160 College St., Toronto, ON M5S 3E1, Canada; Division of Metrology for Quality of Life, Korea Research Institute of Standards and Science, Yuseong-gu, Daejeon 34113, Republic of Korea.
authors.forename: Kihwan
authors.initials: K
authors.lastname: Choi
authors.affiliation: Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 3G1, Canada.
authors.forename: Ezel
authors.initials: E
authors.lastname: Boyacı
authors.affiliation: Department of Chemistry, University of Toronto, 80 St George St., Toronto, ON M5S 3H6, Canada.
authors.forename: Jihye
authors.initials: J
authors.lastname: Kim
authors.affiliation: Department of Chemistry, University of Toronto, 80 St George St., Toronto, ON M5S 3H6, Canada.
authors.forename: Brendon
authors.initials: B
authors.lastname: Seale
authors.affiliation: Department of Chemistry, University of Toronto, 80 St George St., Toronto, ON M5S 3H6, Canada.
authors.forename: Luis
authors.initials: L
authors.lastname: Barrera-Arbelaez
authors.affiliation: Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 3G1, Canada.
authors.forename: Janusz
authors.initials: J
authors.lastname: Pawliszyn
authors.affiliation: Department of Chemistry, University of Toronto, 80 St George St., Toronto, ON M5S 3H6, Canada; Donnelly Centre for Cellular and Biomolecular Research, 160 College St., Toronto, ON M5S 3E1, Canada; Institute of Biomaterials and Biomedical Engineering, University of Toronto, 164 College St., Toronto, ON M5S 3G9, Canada. Electronic address: aaron.wheeler@utoronto.ca.
authors.forename: Aaron R
authors.initials: AR
authors.lastname: Wheeler
mesh_terms: D002623:Chemistry Techniques, Analytical / Q000379:methods*; D002853:Chromatography, Liquid; D006801:Humans; D044085:Microfluidics; D012815:Signal Processing, Computer-Assisted; D052617:Solid Phase Microextraction; D012996:Solutions; D012997:Solvents; D053719:Tandem Mass Spectrometry
chemical_list: D012996:Solutions; D012997:Solvents
keywords: Digital microfluidics; HPLC-MS; Hormone; SPME; Solid-phase microextraction; Steroid; Urine