Sol-gel monolith

Kato, M., Jin, H. M., Sakai-Kato, K., Toyo oka, T., Dulay, M. T., and Zare, R. N. (2003). Determination of glutamine and serine in rat cerebrospinal fluid using capillary electrochromatography with a modified photopolymerized sol-gel monolithic column. /. Chromatogr. A 1004, 209-215. 

The inside of a monolithic electrochromatography column contains silicate fingers" coated with stationary phase. Aromatic compounds were separated with a mean plate number of 80 000 in a 50-cm column with 15-kV applied voltage. [From J. D. Hayes and A. Malik, Sol-Gel Monolithic Columns with Reversed Eleclroosmotic How for Capillary Eleclrochromolography" Anal. Chem. 2000, 72.4090. Photo courtesy A. Malik, University of South Honda.]... 

A pepsin microreactor was developed using a sol-gel monolithic column photo-polymerized within a fused silica capillary [6]. The column was used for on-line ESI CE/MS. Although monolithic microreactors are fast and efficient, the process of their preparation may require more than 24 h and can be difficult to reproduce. 

Wang, S. H., and Hench, L. L., Drying control additives for rapid production of large sol-gel monoliths containing transition and rare earth elements, in Science of Ceramic Chemical Process (L. L. Hench and D. R. Ulrich, eds.), (John Wiley and Sons, New York, 1986), pp. 201-207. 

Eigure 14. A typical experimental setup for examination of the solid-state electrochemistry of a sol-gel monolith. [Adapted from (152).]... 

State pyrene by Cu(II) ion during the sol-to-gel conversion has contributed to understanding of photoinduced electron-transfer mechanisms in sol-gel monoliths (236, 237). The smdy of the charge separation between pyrene and an electron acceptor molecule is more applicable to the discussion of photonics and will be discussed in Section V.B. 

Wu, Q., et al.. Microchip-based macroporous sflica sol-gel monolith for efficient isolation of DNA... 

However, FT-IR measurements showed a large number of Si-OH groups in the imprinted material. In order to prepare a more nonpolar sol -gel, monoliths were prepared as described above, but treated with neat chlorotrimethylsilane (CTMS) prior to template removal. The binding data of the CTMS-treated materials are shown in Table 3. A significant increase in partition coefficients was observed for DDT and all other nonpolar analytes. The highest selectivity was seen for the rebind-... 

Dulay MT, Quirino JP, Bennett BD, Kato M, Zare RN (2001) Photopolymerized sol-gel monoliths for capillary electrochromatography. Anal Chem 73 3921-3926... 

Monolithic CEC columns can be formed from organic porous polymeric monoliths or porous silica sol-gel monoliths. Other monolithic CEC column types, such as immobilized particles, have also been demonstrated but have not shown the potential of the first two types. The monolithic stationary phases are created in situ by polymerization reactions under controlled conditions, such that a porous bed is created. 

In 2004, Leventis et al. [12] presented a study in which they demonstrated that probe-doped silica aerogels could be prepared by post-doping cationic mthenium probes and cationic probe-electron donor dyads into silica sol-gel monoliths. Ruthenium complexes have well-described properties and have been studied extensively by others (as noted in [4, 13]). 

The probe ruthenium(ll) frA-(l, 10-phenanthroline) and the electron donors 4-benzoyl-A-methylpyridinium and A-benzyl-A -methyl viologen were employed by Leventis et al. [12]. A base-catalyzed TMOS precursor recipe was used to prepare silica sol-gel monoliths. The wet gels were then soaked in methanol baths containing one of the dyads, or the mthenium complex, each of which is a cationic species that was taken up by the sol-gels to such an extent that no color was observed in the remaining bath solution. The doped gels... 

Immunoaffinity extraction is a technique often adopted in clinical chemistry. Immu-noaffinity supports contained polyclonal antibodies covalently immobilized on sephar-ose, agarose, or silica supports. Two different kinds of supports, crushed sol-gel monoliths and sol-gel-coated highly porous silica particles, were applied to the extraction of 16 sulfonylureas in food and natural water followed by high-performance liquid chromatography-ultraviolet/diode-array detection (LC-UV/DAD) [32]. 

Trypsin covalently linked to a photopolymerized sol-gel monolith modified by incorporating poly(ethylene glycol) (PSG-PEG) (Scheme 10.13) was described by Dulay and others [126] for on-column digestion of N-a-benzoyl-L-arginine ethyl ester (BAEE) and peptides, neurotensin, and insulin chain B. They prepared a novel IMER by preparation of a reactive hydrophilic macroporous PEG-modified photo-polymerized... 

Chaudhuri S.R., et al. Process and apparatus for rapidly drying a wet porous sol-gel monolith. Ceram. Trans. 1995 55 129... 

L. (2007) Optical determination of Cr(VI) using regenerable, functionalized sol-gel monoliths. Analytica Chimica Acta, 581, 232. 

Figure 10.1 Types of silica-based sol-gel monoliths differing in porosity, (a) Aerogels, highly porous monoliths, (b) Xerogel, semiporous monoliths, (c) Inorganic-organic hybrid, nonporous monoliths.

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