title: Molecularly imprinted polypyrrole encapsulated carbon nanotubes in stainless steel frit for micro solid phase extraction of estrogenic compounds.
abstract: A novel micro-solid phase extraction (microSPE) device was prepared by electrochemically adhering molecularly imprinted polypyrrole encapsulated carbon nanotubes (MIPPy/CNTs) onto a stainless steel frit. It was found that the use of CNTs increased the total binding capacity without compromising the porosity of the frit. Three templates, 17alpha-ethynyl estradiol (EE2), 17beta-estradiol (E2), and ochratoxin A (OTA) were imprinted individually to make their respective MIPPy/CNTs-modified frits. The binding properties of these microSPE devices were characterized by high performance liquid chromatography (HPLC) with fluorescence detection (FLD). In comparison with non-imprinted polypyrrole encapsulated carbon nanotubes (PPy/CNTs), the molecular imprinting technique enhanced the selective binding towards the imprint molecules. MIPPy/CNTs-microSPE-HPLC-FLD results demonstrated the selectivity of MIPPy had been tailored by imprinting with different templates. This is the first report on how versatile pyrrole can be as a functional monomer for the molecular imprinting of target compounds with a broad range of high to low pKa values.
authors.affiliation: Department of Chemistry, Sam Houston State University, Huntsville, Texas, 77341, USA.
authors.forename: Jorn C C
authors.initials: JC
authors.lastname: Yu
authors.forename: Amy
authors.initials: A
authors.lastname: Hrdina
authors.forename: Christina
authors.initials: C
authors.lastname: Mancini
authors.forename: Edward P C
authors.initials: EP
authors.lastname: Lai
mesh_terms: D002851:Chromatography, High Pressure Liquid; D004563:Electrochemistry / Q000379:methods; D004967:Estrogens / Q000737:chemistry / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D008855:Microscopy, Electron, Scanning; D008956:Models, Chemical; D054802:Molecular Imprinting; D036103:Nanotechnology / Q000379:methods*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D009793:Ochratoxins / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D011758:Pyrroles / Q000737:chemistry*; D012680:Sensitivity and Specificity; D052616:Solid Phase Extraction; D013050:Spectrometry, Fluorescence; D013193:Stainless Steel / Q000737:chemistry*
chemical_list: D004967:Estrogens; D037742:Nanotubes, Carbon; D009793:Ochratoxins; D011108:Polymers; D011758:Pyrroles; D013193:Stainless Steel; C025589:ochratoxin A; C067635:polypyrrole