BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Talks.cam//talks.cam.ac.uk//
X-WR-CALNAME:Talks.cam
BEGIN:VEVENT
SUMMARY:Designing Self-Propelled Polymeric Capsules and Gels - Prof Anna C
  Balazs\,  Chemical Engineering Department\, University of Pittsburgh
DTSTART:20080530T131500Z
DTEND:20080530T141500Z
UID:TALK11185@talks.cam.ac.uk
CONTACT:Jurij Kotar
DESCRIPTION:Using simulation and theory\, we demonstrate how nanoparticles
  can be harnessed to regulate the interaction between two initially statio
 nary microcapsules on a surface and promote the self-propelled motion of t
 hese capsules along the substrate. The first microcapsule\, the “signali
 ng” capsule\, encases nanoparticles\, which diffuse from the interior of
  this carrier and into the surrounding solution\; the second capsule is th
 e “target” capsule\, which is initially devoid of particles. Nanoparti
 cles released from the signaling capsule modify the underlying substrate\,
  and thereby initiate the motion of the target capsule. The latter motion 
 activates hydrodynamic interactions\, which trigger the signaling capsule 
 to follow the target. The continued release of the nanoparticles sustains 
 the motion of both capsules. In effect\, the system constitutes a syntheti
 c analogue of biological cell signaling and our findings can shed light on
  fundamental physical forces that control interactions between cells. Our 
 findings can also yield guidelines for manipulating the interactions of sy
 nthetic microcapsules in microfluidic devices. In the second study\, we us
 e computational modeling to investigate how an applied mechanical pressure
  can be harnessed to initiate traveling chemical waves in polymer gels und
 ergoing the Belousov-Zhabotinsky (BZ) reaction. We uncover a rich dynamic 
 behavior\, isolating systems where the applied pressure induces chemical o
 scillations in an initially non-oscillatory system. We also pinpoint a sce
 nario where the compression induces both oscillations and the autonomous r
 otation of the entire sample. Such BZ gels can potentially be used to fabr
 icate touch-sensitive sensors and membranes\, as well as self-reinforcing 
 materials. 
LOCATION:Small Lecture Theatre\, Cavendish Laboratory
END:VEVENT
END:VCALENDAR