We demonstrate steady-state focusing of coherent light through dynamic scattering media. The phase of an incident beam is controlled both spatially and temporally using a reflective, 1020-segment MEMS spatial light modulator, using a coordinate descent optimization technique. We achieve focal intensity enhancement of between 5 and 400 for dynamic media with speckle decorrelation time constants ...

Dielectrophoretic dynamic light-scattering (DDLS) spectroscopy is presented. DDLS identifies macromolecules based on their dielectric, or polarizability, properties. DDLS measurements are carried out in an oscillating, nonuniform electric field. The field induces macromolecules to undergo dielectrophoretic motion, which is detected by the modulation in the dynamic light-scattering autocorrelati...

Semiconductor nanoparticles (quantum dots) are promising fluorescent markers, but it is very little known about interaction of quantum dots with biological molecules. In this study, interaction of CdTe quantum dots coated with thioglycolic acid (TGA) with bovine serum albumin was investigated. Steady state spectroscopy, atomic force microscopy, electron microscopy and dynamic light scattering m...

Recent developments in processing techniques and detection hardware have opened new horizons for the application of light scattering methods based on the dynamic analysis of coherent scattered light. Increased computational power of modern microprocessors allow real-time data evaluation on standard desktop computers. The continuous improvement of detector arrays, such as cameras based on CCD or...

We address experimentally the problem of how the structure of a surface monolayer determines the viscoelasticity of the interface. Optical microscopy and surface quasielastic light scattering have been used to characterize aggregation of CaCO3 particles at the air-water interface. The structures formed by cluster-cluster aggregation are two-dimensional fractals that grow to eventually form a pe...

We introduce a novel light-scattering technique for investigating the dynamics of random media with a broad range of optical densities. By use of the spatial coherence properties of a single-mode optical fiber and the temporal coherence of a broadband source, the measurement volume is isolated at the end of the optical waveguide. Optical mixing between the fluctuating scattered light and the Fr...

UNLABELLED Dengue affects millions of people worldwide. No specific treatment is currently available, in part due to an incomplete understanding of the viral components' interactions with host cellular structures. We tested dengue virus (DENV) capsid protein (C) interaction with low- and very low-density lipoproteins (LDL and VLDL, respectively) using atomic force microscopy-based force spectro...

We have contrasted the behavior of nanoparticles formed by the self-assembly of polymers based on poly(ethylene glycol) (PEG) and poly(D,L-lactide), with linear, linear-dendritic and bottle-brush architectures in biologically relevant media. Polymer PEG content ranged between 14% and 46% w/w, and self-assembly was triggered by a rapid and large change in solvent quality inside a four-stream vor...

A liquid-glass transition was observed experimentally in a new system, an oil-in-water emulsion. Dynamic light scattering was employed to obtain the intermediate scattering function f(q,t) for a range of volume fractions f and scattering vectors q. The results are compared with predictions of the mode coupling theory. While the usual idealized version of the theory provides accurate fits to the...

An initial stage of fibrillogenesis in solutions of glutathione S-transferase-huntingtin (GST-HD) fusion proteins has been studied by using dynamic light scattering. Two GST-HD systems with poly-L-glutamine (polyGln) extensions of different lengths (20 and 51 residues) have been examined. For both systems, kinetics of z-average translation diffusion coefficients (Dapp) and their angular depende...