AVS 56th International Symposium & Exhibition
    Thin Film Monday Sessions
       Session TF2-MoA

Paper TF2-MoA1
Creation of All-Diamond Core-Shell Particles by Layer-by-Layer Deposition for use in Solid Phase Extraction and Chromatography

Monday, November 9, 2009, 2:00 pm, Room B3

Session: Thin Films: Growth and Characterization II
Presenter: G. Saini, Brigham Young University
Authors: G. Saini, Brigham Young University
L.A. Wiest, Brigham Young University
R.C. Davis, Brigham Young University
A. Dadson, U.S. Synthetic
M.A. Vail, U.S. Synthetic
M.L. Lee, Brigham Young University
M.R. Linford, Brigham Young University
Correspondent: Click to Email
We report the formation of all-diamond, core-shell particles for solid phase extraction (SPE) made via layer-by-layer deposition. The process begins with the amine functionalization of microdiamond by its immersion in an aqueous solution of an amine-containing polymer. The amine functionalized microdiamond is then immersed in an aqueous suspension of the nanodiamond, which leads to adsorption of nanodiamond. Alternating immersion in the solution of amine containing polymer and in the suspension of nanodiamond is continued until the desired number of nanodiamond layers is formed around the microdiamond. Finally, the core-shell particles are crosslinked with 1,2,5,6-diepoxycyclooctane to increase their mechanical and chemical stability. Core-shell particles are characterized by diffuse reflectance infrared Fourier transform spectroscopy (DRIFT), environmental scanning electron microscopy (ESEM), X-ray photoelectron spectroscopy (XPS) and Brunauer Emmett Teller (BET) surface area and pore size measurements. Core-shell diamond particles have much higher surface area and analyte loading capacity as measured in SPE than non-porous solid diamond particles. For example, for 50-70 μm core-shell particles containing 9 bilayers of poly(allylamine) (PAAm) and 100-250 nm nanodiamond, which can be made relatively easily, a ca. 21-fold increase in BET surface area and 80-fold increase in analyte loading capacity by SPE was observed in comparison to non-porous solid diamond particles.