Preparation and evaluation of micro and meso porous silica monoliths with embedded carbon nanoparticles for the extraction of non-polar compounds from waters.
A novel hybrid micro and meso porous silica monolith with embedded carbon nanoparticles (Si-CNPs monolith) was prepared inside a fused silica capillary (3cm in length) and used as a sorbent for solid-phase microextraction. The hybrid monolithic capillary was synthetized by hydrolysis and polycondensation of a mixture of tetraethoxysilane (TEOS), ethanol, and three different carbon nanoparticles such as carboxylated single-walled carbon nanotubes (c-SWCNTs), carboxylated multi-walled carbon nanotubes (c-MWCNTs), and oxidized single-walled carbon nanohorns (o-SWNHs) via a two-step catalytic sol-gel process. Compared with silica monolith without carbon nanoparticles, the developed monolithic capillary column exhibited a higher extraction efficiency towards the analytes which can be ascribed to the presence of the carbon nanoparticles. In this regard, the best performance was achieved for silica monolith with embedded c-MWCNTs. The resulted monolithic capillaries were also characterized by scanning electron microscopy (SEM), elemental analysis and nitrogen intrusion porosimetry. Variables affecting to the preparation of the sorbent phase including three different carbon nanoparticles and extraction parameters were studied in depth using polycyclic aromatic hydrocarbons (PAHs) as target analytes. Gas chromatography-mass spectrometry was selected as instrumental technique. Detection limits range from 0.1 to 0.3μgL-1, and the inter-extraction units precision (expressed as relative standard deviation) is between 5.9 and 14.4%.
Department of Analytical Chemistry, Institute of Fine Chemistry and Nanotechnology, Marie Curie Building, Campus of Rabanales, University of Córdoba, 14071 Córdoba, Spain.
Beatriz
B
Fresco-Cala
Department of Analytical Chemistry, Institute of Fine Chemistry and Nanotechnology, Marie Curie Building, Campus of Rabanales, University of Córdoba, 14071 Córdoba, Spain.
Soledad
S
Cárdenas
Department of Analytical Chemistry, Institute of Fine Chemistry and Nanotechnology, Marie Curie Building, Campus of Rabanales, University of Córdoba, 14071 Córdoba, Spain. Electronic address: qa1meobj@uco.es.
Miguel
M
Valcárcel
D008401:Gas Chromatography-Mass Spectrometry; D008855:Microscopy, Electron, Scanning; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D037742:Nanotubes, Carbon / Q000737:chemistry*; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis / Q000302:isolation & purification; D012821:Silanes / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry*; D052617:Solid Phase Microextraction / Q000379:methods*; D014867:Water / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000302:isolation & purification
D037742:Nanotubes, Carbon; D011084:Polycyclic Aromatic Hydrocarbons; D012821:Silanes; D014874:Water Pollutants, Chemical; D014867:Water; C040733:tetraethoxysilane; D012822:Silicon Dioxide
Carbon nanoparticles; Monolithic hybrid solid; Polycyclic aromatic hydrocarbons; Silica monolith; Solid-phase microextraction