title: Endotoxin-induced structural transformations in liquid crystalline droplets.
abstract: The ordering of liquid crystals (LCs) is known to be influenced by surfaces and contaminants. Here, we report that picogram per milliliter concentrations of endotoxin in water trigger ordering transitions in micrometer-size LC droplets. The ordering transitions, which occur at surface concentrations of endotoxin that are less than 10(-5) Langmuir, are not due to adsorbate-induced changes in the interfacial energy of the LC. The sensitivity of the LC to endotoxin was measured to change by six orders of magnitude with the geometry of the LC (droplet versus slab), supporting the hypothesis that interactions of endotoxin with topological defects in the LC mediate the response of the droplets. The LC ordering transitions depend strongly on glycophospholipid structure and provide new designs for responsive soft matter.
authors: Department of Chemical and Biological Engineering, University of Wisconsin-Madison, 1415 Engineering Drive, Madison, WI 53706-1607, USA.
authors: I-Hsin
authors: IH
authors: Lin
authors: Daniel S
authors: DS
authors: Miller
authors: Paul J
authors: PJ
authors: Bertics
authors: Christopher J
authors: CJ
authors: Murphy
authors: Juan J
authors: JJ
authors: de Pablo
authors: Nicholas L
authors: NL
authors: Abbott
references: Science. 1997 Mar 21;275(5307):1770-3
references: 9065396
references: Science. 2006 Aug 18;313(5789):954-8
references: 16917058
references: J Am Chem Soc. 2008 Apr 2;130(13):4326-33
references: 18335929
references: Faraday Discuss. 2010;144:159-69; discussion 203-22, 467-81
references: 20158028
references: Science. 2010 Jan 1;327(5961):60-4
references: 20044569
references: Phys Rev Lett. 2007 Oct 12;99(15):157801
references: 17995213
references: Annu Rev Biochem. 2002;71:635-700
references: 12045108
references: Science. 2003 Dec 19;302(5653):2094-7
references: 14684814
references: Nature. 2008 Oct 2;455(7213):606-7
references: 18833268
references: Nature. 2000 Jun 29;405(6790):1030-3
references: 10890438
references: Science. 2001 Mar 30;291(5513):2576-80
references: 11283364
references: Langmuir. 2008 Jan 15;24(2):541-6
references: 18081328
references: Science. 1999 Jan 8;283(5399):209-12
references: 9880250
references: Nature. 2002 Dec 19-26;420(6917):885-91
references: 12490963
references: Science. 1998 Aug 14;281(5379):945-50
references: 9703502
references: Phys Rev E Stat Nonlin Soft Matter Phys. 2008 Mar;77(3 Pt 1):031705
references: 18517404
references: Angew Chem Int Ed Engl. 2009;48(9):1652-5
references: 19156793