In situ ATR-FTIR investigation on the preparation and enantiospecificity of chiral polyelectrolyte multilayers.
Chiral polyelectrolyte multilayers (PEMs) consisting of poly(l-lysine) (PLL), poly(N-(S)alkylated 4-vinylpyridinium iodide), or poly(ethyleneimine maltose) (PEI-m) as polycations and poly(styrenesulfonic acid) sodium salt (PSS) or poly(vinyl sulfate) as polyanions, as well as a nonchiral PEM composed of poly(ethyleneimine) (PEI) and PSS were deposited on silicon substrates and poly(tetrafluoroethylene) membranes using the layer-by-layer method. For these PEMs, enantiospecific interaction toward one enantiomer of either l/d-glutamic acid (l/d-GLU), l/d-tryptophan, or l/d-ascorbic acid (l/d-ASC), respectively, was studied under variation of the concentration, pH, and ionic strength. Both deposition and enantiospecific interaction were analyzed by attenuated total reflection Fourier transform infrared spectroscopy. Our results show a significant enantiospecific preference of d-GLU over l-GLU at PEMs containing PLL and of d-ASC over l-ASC at PEMs containing PEI-m. No such enantiospecific preference was found for nonchiral PEMs containing PEI. The enantiospecificity of PEMs of PLL/PSS toward l/d-GLU could be significantly influenced by the ionic strength and pH values, so that increasing attractive electrostatic interactions resulted in higher enantiospecificity.
Ouyang
Wuye
W
Leibniz-Institute of Polymer Research Dresden eV (IPF), Hohe Strasse 6, 01069 Dresden, Germany.
Müller
Martin
M
Appelhans
Dietmar
D
Voit
Brigitte
B
D001205:Ascorbic Acid / Q000737:chemistry*; D004573:Electrolytes / Q000737:chemistry*; D018698:Glutamic Acid / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D009994:Osmolar Concentration; D010539:Permeability; D000071228:Polyelectrolytes; D011107:Polylysine / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013237:Stereoisomerism; D013451:Sulfonic Acids; D014364:Tryptophan / Q000737:chemistry*
D001205:Ascorbic Acid; D004573:Electrolytes; D018698:Glutamic Acid; D000071228:Polyelectrolytes; D011107:Polylysine; D011108:Polymers; D013451:Sulfonic Acids; D014364:Tryptophan; C077114:styrenesulfonic acid polymer