Tracking Bulk and Interfacial Diffusion Using Multiplex Coherent Anti-Stokes Raman Scattering Correlation Spectroscopy.

ABSTRACT: Multiplex coherent anti-Stokes Raman scattering correlation spectroscopy (CARS-CS) is shown as a label-free, chemically specific approach for monitoring the molecular mobility of particles in solution and at interfaces on the millisecond time scale. The CARS spectral range afforded by broadband excitation facilitates a quantitative measurement for the number of particles in the focal volume, whereas the autocorrelation of spectral data elucidates dynamic events, such as diffusion. The measured diffusion coefficients for polymer beads ranging from 100 nm to 1.1 μm in diameter are on the order of 10(-8)-10(-9) cm(2)/s, in good agreement with predicted Stokes-Einstein values. Diffusion at different interfaces shows particles are fastest in bulk medium, marginally slower at the liquid/glass in

SUBMITTER: Bailey KA 

PROVIDER: S-EPMC4962611 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature