Fluorescence microscopy and microfluidic techniques for studying interactions between antifreeze proteins and ice surfaces

COMP 16

Ido Braslavsky, braslavs@ohio.edu1, Natalya Pertaya, natalya_pertaya@yahoo.com1, Yeliz Celik, celik@helios.phy.ohio.edu1, Alex Groisman, agroisman@ucsd.edu2, JS. Wettlaufer, john.wettlaufer@yale.edu3, and Peter L. Davies, daviesp@post.queensu.ca4. (1) Physics and Astronomy, Ohio University, Clippinger Labs 251B, Athens, OH 45701, (2) Department of Physics, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0354, (3) Departments of Geology & Geophysics and Physics, Yale University, 210 Whitney Avenue, New Haven, CT 06520-8109, (4) Department of Biochemistry, Queen’s University, Kingston, ON K7L 3N6, Canada
Antifreeze proteins (AFPs) have many potential applications in systems where controlling ice crystal growth is desired. However, the mechanisms underlying the interactions between AFPs and ice surfaces are only partially understood. To elucidate these interactions, and the factors driving AFP activity, we directly visualized fluorescently labeled AFPs on ice crystals in supercooled solutions, using a microfluidics device which allowed high signal-to-noise fluorescence monitoring combined with the ability to modify the solution around the ice crystals. This method enabled us to directly examine characteristics such as the kinetics of attachment, ice orientation preference, and surface density of AFPs, and thus to assess existing theories for AFP activity. We developed microfluidic devices for studying systems under both isothermal conditions and with controlled gradients. The ability to exchange the solute around the crystals while monitoring the locations and binding kinetics of AFPs opens new avenues for research into ice crystal growth inhibition. Supported by CIHR, NSF, and OU-BNNT.

 

Antifreeze Proteins: A Memorial Symposium for Robert Feeney
8:30 AM-12:05 PM, Sunday, August 19, 2007 BCEC -- 162A, Oral

Division of Computers in Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007