Abbott Research Group - UW Chemical and Biological Engineering
Laboratory for Molecular Engineering
Department of Chemical and Biological Engineering
Ordering of Liquid Crystals on Bio/Chemically Functionalized Interfaces
Identified a new molecular mechanism for surface-induced ordering of liquid crystals based on the presentation of transition metal ion complexes at surfaces, and the incorporation of ligands (e.g., nitrile groups) into liquid crystals (Science 2001). This finding led to the demonstration that ligand-exchange reactions can trigger ordering transitions in liquid crystals and thereby selectively report the presence of organophosphorous, organonitrogen and organosulfur compounds (J.Phys.Chem B, 2004 and 2006). Detection of 1 part-per-billion of gaseous dimethylmethylphosphonate was demonstrated within 10sec; selective detection of GA, GB, GD and VX was also demonstrated (Sensors and Actuators B, 2007).
Optical images (between crossed polars) of E7 supported on perchlorate salts of (a) aluminum, (b) zinc(II) and (c) iron(III) before (top row and after (bottom row) exposure to organophosphorus nerve agents. The duration of agent exposure is indicated. Imaged areas are approximately 7.5 mm by 7.5mm