Potentiometric titration of poly(vinylpyridines) and hydrophobic interaction in the counterion binding

The relative basicity of fifteen methylethoxysilylalkylamines of the type (CH3)3-m(C2H5O)m.Si(CH2)nNH2 in acetone has been studied by potentiometric titration. For n 1 the basicity increases with increasing m, which is likely due to increasing electronic interaction of the oxygen of acetone with the silicon of silylalkylamines. The basicity of silylmethylamines (n = 1) changes nonsystematically, probably as a consequence of the competing action of opposite effects.

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Synthesis and properties of 5-phenoxyfurancarboxylic acids

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19800910 ◽

1980 ◽

Vol 45 (3) ◽

pp. 910-913 ◽

Cited By ~ 1

Author(s):

Viera Knoppová ◽

Anton Beňo ◽

Jaroslav Kováč

Keyword(s):

Transfer Coefficient ◽

Potentiometric Titration ◽

Transfer Effect ◽

Furan Series ◽

Oxygen Bridge

Furancarboxylic acids were prepared by oxidation with Ag2O of the corresponding 5-(X-phenoxy)-2-furaldehydes (X = 4-OCH3, 4-SCH3, 3-NHCOCH3, 4-Cl, 4-Br, 4-COOC2H5, 3-NO2, and 4-NO2. The appearing pKa values of the synthesized acids were determined by potentiometric titration. The transfer effect of the substituents through the oxygen bridge is discussed and the transfer coefficient is compared with π' values of other linking groups in the furan series.

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Purification of Glycerol Kinase by "Dye-Ligand" Chromatography and Hydrophobic Interaction Chromatography on Bead-Cellulose Derivatives

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19930445 ◽

1993 ◽

Vol 58 (2) ◽

pp. 445-451 ◽

Cited By ~ 7

Author(s):

Vladimír Žúbor ◽

Albert Breier ◽

Marta Horváthová ◽

Dagmar Hagarová ◽

Peter Gemeiner ◽

...

Keyword(s):

Hydrophobic Interaction ◽

Specific Activity ◽

Hydrophobic Interaction Chromatography ◽

Glycerol Kinase ◽

Enzymic Activity ◽

Cellulose Derivatives ◽

Long Term Storage ◽

Bead Cellulose ◽

Term Storage

The crude extract of cytosole enzymes was obtained from homogenized cells of Saccharomyces cerevisiae by partition. The enzyme was then isolated from the lower aqueous phase displaying higher glycerol kinase activity by dye-ligand chromatography on Cibacron Blue (CB) or Remazol Brilliant Blue R (RB)-derivatized bead-cellulose, ATP being the eluent. The specific activity of glycerol kinase rised more than 10 and 7-times after affinity dye-ligand chromatography and hydrophobic interaction chromatography, respectively. Glycerol kinase obtained by the latter method was purified by CB-bead cellulose. The final preparation maintained its enzymic activity without noticeable losses during a long-term storage at 4 °C in dark.

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