title: Application of 2D-fluorescence spectroscopy for on-line monitoring of pseudoenantiomeric transformations in supercritical carbon dioxide systems.
abstract: 2D-Fluorescence spectroscopy has been shown to be effective for the on-line monitoring of spectroscopic detectable substrates L-phenylalanine-7-amido-4-methylcoumarine (L-PheAMC) and D-phenylalanine-7-amido-4-trifluoromethylcoumarine (D-PheAFC) in supercritical carbon dioxide. Earlier investigations with the coumarine substrates in watery and organic phases showed their potential for on-line enantiomeric evaluations of enzymatic reactions in different reaction media. The solubility of the different substrates and their fluorescence maximums were investigated in SCCO2. The sole hydrolyzations of L-PheAMC and D-PheAFC with alpha-chymotrypsin and the esterase from porcine liver were tracked on-line in the supercritical medium; however, different solubility characteristics of the methyl- and trifluoromethyl-substituted coumarins influence the simultaneous detection of the L- and D-substrate within the applied high-pressure reactor system.
authors.affiliation: Institut für Organische Chemie der Universität Hannover, Schneiderberg 1b, 30167 Hannover, Germany.
authors.forename: Torsten
authors.initials: T
authors.lastname: Knüttel
authors.forename: Hartmut
authors.initials: H
authors.lastname: Meyer
authors.forename: Thomas
authors.initials: T
authors.lastname: Scheper
mesh_terms: D002245:Carbon Dioxide / Q000737:chemistry*; D002918:Chymotrypsin / Q000378:metabolism; D006868:Hydrolysis; D007536:Isomerism; D009862:Online Systems; D010649:Phenylalanine / Q000737:chemistry / Q000378:metabolism; D013050:Spectrometry, Fluorescence / Q000295:instrumentation* / Q000379:methods*; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D002245:Carbon Dioxide; D010649:Phenylalanine; D002918:Chymotrypsin