title: Chemical and biological sensing using liquid crystals.
abstract: The liquid crystalline state of matter arises from orientation-dependent, non-covalent interaction between molecules within condensed phases. Because the balance of intermolecular forces that underlies formation of liquid crystals is delicate, this state of matter can, in general, be easily perturbed by external stimuli (such as an electric field in a display). In this review, we present an overview of recent efforts that have focused on exploiting the responsiveness of liquid crystals as the basis of chemical and biological sensors. In this application of liquid crystals, the challenge is to design liquid crystalline systems that undergo changes in organization when perturbed by targeted chemical and biological species of interest. The approaches described below revolve around the design of interfaces that selectively bind targeted species, thus leading to surface-driven changes in the organization of the liquid crystals. Because liquid crystals possess anisotropic optical and dielectric properties, a range of different methods can be used to read out the changes in organization of liquid crystals that are caused by targeted chemical and biological species. This review focuses on principles for liquid crystal-based sensors that provide an optical output.
authors.affiliation: Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706.
authors.forename: Rebecca J
authors.initials: RJ
authors.lastname: Carlton
authors.affiliation: Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706.
authors.forename: Jacob T
authors.initials: JT
authors.lastname: Hunter
authors.affiliation: Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706.
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Miller
authors.affiliation: Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706.
authors.forename: Reza
authors.initials: R
authors.lastname: Abbasi
authors.affiliation: Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706.
authors.forename: Peter C
authors.initials: PC
authors.lastname: Mushenheim
authors.affiliation: Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706.
authors.forename: Lie Na
authors.initials: LN
authors.lastname: Tan
authors.affiliation: Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706.
authors.forename: Nicholas L
authors.initials: NL
authors.lastname: Abbott
keywords: DNA; Liquid crystals; anchoring transitions; bacteria; biological sensors; biomolecular interfaces; cells; chemical sensors; chemically functionalized interfaces; lipids; nerve agents; proteins; surfaces; toxic chemicals; viruses