Design of Biomolecular Interfaces Using Liquid Crystals Containing Oligomeric Ethylene Glycol

Authors

  • Zhongqiang Yang,

    1. Department of Chemical and Biological Engineering University of Wisconsin-Madison 1415 Engineering Drive, Madison, WI 53706 (USA)
    Search for more papers by this author
  • Jugal K. Gupta,

    1. Department of Chemical and Biological Engineering University of Wisconsin-Madison 1415 Engineering Drive, Madison, WI 53706 (USA)
    Search for more papers by this author
  • Kenji Kishimoto,

    1. Department of Chemistry and Biotechnology School of Engineering, The University of Tokyo Tokyo 113-8656 (Japan)
    Search for more papers by this author
  • Yoshiko Shoji,

    1. Department of Chemistry and Biotechnology School of Engineering, The University of Tokyo Tokyo 113-8656 (Japan)
    Search for more papers by this author
  • Takashi Kato,

    Corresponding author
    1. Department of Chemistry and Biotechnology School of Engineering, The University of Tokyo Tokyo 113-8656 (Japan)
    • Department of Chemistry and Biotechnology School of Engineering, The University of Tokyo Tokyo 113-8656 (Japan)
    Search for more papers by this author
  • Nicholas L. Abbott

    Corresponding author
    1. Department of Chemical and Biological Engineering University of Wisconsin-Madison 1415 Engineering Drive, Madison, WI 53706 (USA)
    • Department of Chemical and Biological Engineering University of Wisconsin-Madison 1415 Engineering Drive, Madison, WI 53706 (USA)
    Search for more papers by this author

Abstract

An investigation of nematic liquid crystals (LCs) formed from miscible mixtures of 4-cyano-4′-pentylbiphenyl (5CB) and 2-(2-[2-{2-(2,3-difluoro-4-{4-(4-trans-pentylcyclohexyl)-phenyl-phenoxy)ethoxy}ethoxy]ethoxy)ethanol (EG4-LC) is reported, the latter being a mesogen with a tetra(ethylene glycol) tail. Quantitative characterization of the ordering of this LC mixture at biologically relevant aqueous interfaces reveals that addition of EG4-LC (1%–5% by weight) to 5CB causes a continuous transition in the ordering of the LC from a planar (pure 5CB) to a perpendicular (homeotropic) orientation. The homeotropic ordering is also seen in aqueous dispersions of micrometer-sized droplets of the LC mixture, which exhibit enhanced stability against coalescence. These observations and others, all of which suggest partitioning of the EG4-LC from the bulk of the LC to its aqueous interface, are complemented by measurements of the adsorption of bovine serum albumin to the aqueous–LC interface. Overall, the results demonstrate a general and facile approach to the design of LCs with interfaces that present biologically relevant chemical functional groups, assume well-defined orientations at aqueous interfaces, and lower non-specific protein adsorption. The bulk of the LC serves as a reservoir of EG4-LC, thus permitting easy preparation of these interfaces and the potential for spontaneous repair of the EG4-decorated interfaces during contact with biological systems.

Ancillary