Imidazoles immobilization

Schuster M, Meyer WH, Wegner G et al (2001) Proton mobility in oligomer-bound proton solvents Imidazole immobilization via flexible spacers. Solid State Ionics 145 85-92... 

Sauk, J., Byun, J., and Kim, H. (2005). Composite Nafion/polyphenylene oxide (PPO) membranes with phosphomolybdic acid (PMA) for direct methanol fuel cells. J. Power Sources 143, 136. Savadogo, O. (2004). Emerging membranes for electrochemical systems. Part II. High temperature composite membranes for polymer electrolyte fuel cell (PEFC) applications. J. Power Sources 127,135. Schuster, M., Meyer, W. H., Wegner, G., Herz, H. G., Ise, M., Schuster, M., Kreuer, K. D., and Maier, J. (2001). Proton mobihty in ohgomer-bound proton solvents Imidazole immobilization via flexible spacers. Solid State Ionics 145, 85. 

Ferric ion was immobilized on a Chelating Sepharose Fast Flow column preparatory to the separation of seven enkephalin-related phosphopep-tides.17 Non-phosphorylated peptides flowed through the column, and the bound fraction contained the product. The capacity of the column was found to be 23 pmol/mL by frontal elution analysis. Cupric ion was immobilized on Chelating Superose for the isolation of bovine serum albumin.18 Cupric ion was immobilized on a Pharmacia HiTrap column for the separation of Protein C from prothrombin, a separation that was used to model the subsequent apparently successful separation of Factor IX from prothrombin Factor IX activity of the eluate was, however, not checked.19 Imidazole was used as the displacement agent to recover p-galactosidase from unclarified homogenates injected onto a nickel-loaded IMAC column.20 Pretreatment with nucleases and cleaning in place between injections were required procedures. A sixfold purification factor was observed. 

The effect of structural modification to 22 on the binding efficiency and binding dynamics of hairpin DNA immobilized on metal surfaces were studied using surface plasmon resonance.124,125 The association and dissociation kinetics were analyzed using a sequential model for the binding of the imidazole containing polyamides... 

Figure 3 Biosynthesis and purification of 90-kD elastin analogue analyzed by denaturing polyacrylamide gel electrophoresis (10-15% gradient, visualized by silver staining). Lanes 1-7 time course of target protein expression at 0, 30, 60, 90, 120, 150, and 180 minutes after induction. Lane 9 soluble lysate of induced E. coli expression strain BLR(DE3)pRAMl. Lanes 10-13 protein fractions obtained from immobilized metal affinity chromatography of the lysate on nickel-NTA agarose (imidazole gradient elution). Lanes 8,14 protein molecular weight standards of 50, 75, 100, and 150 kD.

Nafion " with intercalated heterocycles. Conductivities of >10 S/cm are easily accessible by such systems however, the volatility of the heterocycles requires some immobilization. The effect of covalent immobilization on proton conductivity is shown in Figure 23 for imidazole-based... 

Figure 23. Evolution of proton conductivity of imidazole-based systems with increasing immobilization from the monomer via oligomers to fully polymeric systems.

Scheme 8.4 Grafting of isocyanate-telchelic poly(l, 3-di(l -mesityl)-4- [(bicyclo[2.2.1 ]hept-5-en-2-ylcarbonyl)oxy]methyl -4,5-dihydro-l H-imidazol-3-ium tetrafluoroborate) on silica and generation of the immobilized second generation Grubbs catalyst.

PS-BEMP). The reaction gave 4,5-disubsituted isothiazole in 58% yield. What was interesting was that an additional washing of the immobilized base with an electrophile (in a typical setup, 2,4 -dibromoacetophenone) gave the corresponding 1,4,5-trisubstimted imidazole in 38% yield and >95% purity. Additional efforts were done to produce only the imidazole structure by using the premixed electrophile and ethyl isothiocyanate, however, without success. 

In some processes, there is a need to immobilize dyes, either temporarily as in the case of filter and antihalation devices or permanently as for the images in colour image transfer processes. Because the dyes normally used in these applications contain acid functional groups, the corresponding mordants are basic in nature and are usually polymeric. Polyvinyl-pyridines have utility as mordants. Other useful compounds are illustrated by the pyridinium salt (95) (49USP2484430), the morpholinium salt (96) (72BRP1245952) and the imidazole (97) (72GEP2150136). 

Histidine and histamine derivatives, as well as other imidazoles, have been successfully immobilized by N-tritylation of the imidazole ring with trityl chloride resin [534] (Entry 2, Table 3.29 see also Section 15.8) or with 2-chlorotrityl chloride resin [535-537]. Histidine can also be linked to insoluble supports as the N-dinitrophenyl deriva-... 

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