AVS 61st International Symposium & Exhibition
    Thin Film Wednesday Sessions
       Session TF+EM+EN-WeA

Paper TF+EM+EN-WeA7
Porous Solid Phase Microextraction (SPME) Fibers by Oblique Angle Deposition

Wednesday, November 12, 2014, 4:20 pm, Room 307

Session: Thin Film and Nanostructured Coatings for Light Trapping, Extraction, and Plasmonic Applications
Presenter: Anubhav Diwan, Brigham Young University
Authors: A. Diwan, Brigham Young University
B. Singh, Brigham Young University
M. Kaykhaii, Sistan & Balouchestan University, Iran (Islamic Republic of)
B. Paul, University of Tasmania, Australia
P. Nesterenko, University of Tasmania, Australia
M.R. Linford, Brigham Young University
Correspondent: Click to Email
Solid phase microextraction (SPME) is a solvent-free technique used for extracting organic compounds from matrices such as air or wastewater. It involves a fiber coated with a liquid or solid stationary phase that extracts target compounds directly from a solution or from the head space above a solution or material. Solid stationary phases provide faster extraction than liquid phases, but exhibit lower capacities. Porous solid phases have been able to overcome these issues by providing large surface areas for analyte adsorption. Commercial SPME fibers are rather expensive, swell in many solvents, and often extract limited numbers of compounds (show limited selectivity). Herein, we discuss the preparation of porous SPME fibers by oblique angle deposition (OAD) of sputtered silicon or other materials onto a fiber. OAD involves deposition of materials onto substrates placed at steep angles with respect to the direction of the incoming species, creating porous structures. The resulting nanoporous coatings can be modified with different functional groups to enhance selectivity of the phase towards target compounds. If normalized for thickness, our fibers show ca. three times the capacity of a commercial, 7 μm PDMS fiber. To confirm their morphologies, new OAD-based fibers have been characterized by scanning electron microscopy (SEM). Various silane coatings can be applied to our fibers, which will offer a range of selectivities. These coatings, e.g., a C18 silane, have been characterized on model planar substrates by X-ray photoelectron spectroscopy (XPS) and contact angle goniometry (wetting).