In situ ATR-FTIR investigation on the preparation and enantiospecificity of chiral polyelectrolyte multilayers

ACS Appl Mater Interfaces. 2009 Dec;1(12):2878-85. doi: 10.1021/am900597c.

Abstract

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Ascorbic Acid / chemistry*
  • Electrolytes / chemistry*
  • Glutamic Acid / chemistry*
  • Hydrogen-Ion Concentration
  • Osmolar Concentration
  • Permeability
  • Polyelectrolytes
  • Polylysine / chemistry
  • Polymers / chemistry*
  • Spectroscopy, Fourier Transform Infrared
  • Stereoisomerism
  • Sulfonic Acids
  • Tryptophan / chemistry*

Substances

  • Electrolytes
  • Polyelectrolytes
  • Polymers
  • Sulfonic Acids
  • polyanions
  • Polylysine
  • Glutamic Acid
  • Tryptophan
  • Ascorbic Acid
  • styrenesulfonic acid polymer