Center for Nonlinear Studies

Friday, June 17, 20113:00 PM - 4:00 PMCNLS Conference Room (TA-3, Bldg 1690)
Seminar
Stokes Shifts as a Surrogate for Debye Waller Factors, and the Relationship Between Picosecond Dynamics and Alpha Relaxation
Marcus T CiceroneBiomaterials Group NIST, Gaitersburg, Maryland
For decades, proteins have been stabilized for biotechnology applications by drying them in the presence of sugars. Engineering of the dried sugar (glassy) formulations is currently based on a combination of weakly predictive metrics and long-term stabilization studies. I will show that short-time dynamics in the glass (fast β relaxation), contains a signature that is strongly predictive of long-term protein stability, and will discuss potential reasons for this surprising relationship. I will further show that short-time behavior characteristic of fast β relaxation seen in the intermediate scattering function can be obtained from time-resolved Stokes shifts (TRSS) in glassforming materials. Debye-Waller factor () analogs, extracted from the TRSS data of four glassforming liquids will be compared with neutron scattering to evaluate the robustness of this procedure. I will also comment on putative relationships between α and fast β relaxation.

Host: Turab Lookman, T-4, txl@lanl.gov, 665-0419