Controlled pore glass immobilized

Figure 2. Activity Profile for Control Pore Glass Immobilized Alcohol Oxidase.

Off-line dicarbamate solvent extraction and ICP-MS analysis [317] provided part-per-trillion detection limits Cd (0.2 ppt), Co (0.3 ppt), Cu (3 ppt), Fe (21 ppt), Ni (2 ppt), Pb (0.5 ppt), and Zn (2 ppt). Off-line matrix removal and preconcentration using cellulose-immobilized ethylenediaminetetraacetic acid (EDTA) have also been reported [318]. Transition metals and rare earth elements were preconcentrated and separated from the matrix using on-line ion chromatography with a NTA chelating resin [319]. Isotope-dilution-based concentration measurement has also been used after matrix separation with a Chelex ion-exchange resin [320]. The pH, flow rate, resin volume, elution volume, and time required for isotope equilibration were optimized. A controlled-pore glass immobilized iminodiacetate based automated on-line matrix separation system has also been described [321]. Recoveries for most metals were between 62% and 113%. 

Figure 2, Flow system for seawater sampling/pre-concentrating on controlled pore glass immobilized 8-hydroxyquinoline (CPG-8HOQ)...

S.M. Nelms, G.M. Greenway, and D. Koller. Evaluation of controlled-pore glass immobilized iminodiacetate as a reagent for automated on-line matrix separation for inductively coupled plasma mass spectrometry. Journal of Analytical Atomic Spectrometry 11 907-911, 1996. 

MWNTs favored the detection of insecticide from 1.5 to 80 nM with a detection limit of InM at an inhibition of 10% (Fig. 2.7). Bucur et al. [58] employed two kinds of AChE, wild type Drosophila melanogaster and a mutant E69W, for the pesticide detection using flow injection analysis. Mutant AChE showed lower detection limit (1 X 10-7 M) than the wild type (1 X 10 6 M) for omethoate. An amperometric FIA biosensor was reported by immobilizing OPH on aminopropyl control pore glass beads [27], The amperometric response of the biosensor was linear up to 120 and 140 pM for paraoxon and methyl-parathion, respectively, with a detection limit of 20 nM (for both the pesticides). Neufeld et al. [59] reported a sensitive, rapid, small, and inexpensive amperometric microflow injection electrochemical biosensor for the identification and quantification of dimethyl 2,2 -dichlorovinyl phosphate (DDVP) on the spot. The electrochemical cell was made up of a screen-printed electrode covered with an enzymatic membrane and combined with a flow cell and computer-controlled potentiostat. Potassium hexacyanoferrate (III) was used as mediator to generate very sharp, rapid, and reproducible electric signals. Other reports on pesticide biosensors could be found in review [17],... 

The prototype reaction was the hydroformylation of oleyl alcohol (water insoluble) with a water-soluble rhodium complex, HRh(C0)[P(m-C6H4S03Na)3]3 (Figure 6.5). Oleyl alcohol was converted to the aldehyde (yield = 97%) using 2 mol % Rh with respect to the substrate and cyclohexane as the solvent, at 50 atmospheres CO/H2, and 100°C. The SAPCs were shown to be stable upon recycling, and extensive work proved that Rh is not leached into the organic phase. Since neither oleyl alcohol nor its products are water soluble, the reaction must take place at the aqueous-organic interface where Rh must be immobilized. Also, if the metal catalyst was supported on various controlled pore glasses with... 

The characteristics of a support material are of great importance to the measured enzyme activity [79, 101]. Hydrophobic carriers have a low ability to attract water, thus leaving more available for the enzyme, hence Wehtje et al. [102, 103] have shown that celite is a suitable carrier for the PaHnl to yield an immobilized form of the enzyme. In contrast, controlled pore glass (CPG) and Sephadex G25 were found to be less well suited to enzyme support as, using these systems, cyanohydrin synthesis was significantly reduced (over 30%). Sephadex also promoted the spontaneous addition of HCN to benzaldehyde [102]. A series of batch experiments showed that if the solvent (diisopropyl ether) surrounding the immobilised PaHnl contained insufficient water (i. e. less than 2 %), it would be extracted from the enzyme preparation and consequently enzyme activity was lost [102]. These results were the basis for the production... 

In solid-phase syntheses, oligonucleotides are usually synthesized in the 5 -direction from an immobilized 3 -terminus. The solid phase is generally silica or controlled pore glass (CPG), which has been... 

ThechemiluminescentreactionbetweenZ>w(2,4,6-trichlorophenyl)oxalate (TCPO) and hydrogen peroxide in the presence of perylene was used by Seitz et al. to develop what is seemingly a prototype for the determination of HjOj based on glucose oxidase immobilized on controlled pore glass... 

SAP catalysts have also been applied in the Wacker oxidation584 of higher olefins where the separation of products from the catalyst is cumbersome. Palladium(II) and copper(II) salts immobilized on controlled pore glass CPG-240 in the presence of water catalysed the oxidation of 1-heptene to 2-heptanone in conversions up to 24%.585 Significant isomerization to 2-heptene and 3-heptene (isomerization/oxidation=2/3) was also observed. However, an advantage of SAP-Wacker oxidation catalysts over classical systems is that the Cu(II) is confined to the support and therefore not corrosive whereas aqueous Cu2+ is very corrosive to steel. 

Torriero et al. [61] l-Lactate Milk L-Lactate oxidase (LOx) and peroxidase (HRP)/LOx on 3-aminopropyl-modified controlled-pore glass reactor HRP and Os-PAA were covalently immobilized on the electrode surface Glassy carbon electrode/O vs. Ag/AgCl Redox polymer... 

Highly porous silica gel served as a support for the TADDOL moiety derived from inexpensive and readily available i-tartaric acid, which provided access to htanium-based Lewis acid catalysts (Heckel, 2000). Such entihes are employed successfully for enantioselective reactions. TADDOLs were covalently attached to the trimethyl-silyl-hydrophobized silica gel, controlled-pore glass (CPG) at about 300 m2 g-1, at a loading of 0.3-0.4 mmol gl (Heckel, 2002). In a carefully monitored mulh-step immobilization procedure, the TADDOLs were titanated to yield dichloro-, diisopropyl-, or ditosyl-TADDOLates. These catalysts were employed in dialkylzinc addihon to benzaldehydes and diphenyl nitrone addihon to 3-crotonyloxazolidinone, a [3+2] cycloaddition. 

A. HECKELand D. Seebach, Preparation and characterization of TAD DO Ls immobilized on hydrophobic controlled-pore-glass silica gel and their use in enantioselective heterogeneous catalysis, Chem - Eur.J. 2002, 8, 559-572. 

Gunnlaugsdottir, H. Wannerberger, K. Sivik, B. Alcoholysis and Glyceride Synthesis with Immobilized Lipase on Controlled-Pore Glass of Varying Hydrophobicity in Supercritical Carbon Dioxide. Enzyme Microb. Technol. 1998b, 22, 360-67. 

Figure 6.2 Effect of immobilization chemistry on the linewidth of compound s in solution. 1D 1 H spectra of the aromatic protons of phosphotyrosine (pY) are shown with the fitted linewidth. From top to bottom, pY in solution, in the presence of Actigel ALD, streptavidin Sepharose, Zn-IDAA Sepharose> Zn-NFA Sepharose, Zn-NFA silica and controlled-pore glass beads (for comparison).

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