Dynamic Light Scattering Instrument

Access or consultation: Dr. Vladimir Ermolenkov, 591-8890 or vermolenkov@albany.edu

DynaPro Titan is a dynamic light scattering (DLS) instrument that can be used for a broad range of applications requiring both accuracy and high sensitivity. It is well suited for studies of nanoparticles, proteins, vesicles, and colloids. The samples have to be filtered to eliminate dust particles, which might interfere with the signal from the molecules being measured. Experimental solution is injected into a quartz cuvette which is placed into the Microsampler module of the instrument and illuminated by the laser. The specially designed cuvette needs only 12 ml of sample. The scattered light is correlated in the DynaPro host unit which then sends the results to the PC for analysis by the Dynamics software. The DLS size range is 1-1000 nm. The integrated temperature controller allows studying samples at various temperatures ranging from -4°C to 80°C. For protein solutions, the concentration of 1-2 mg/ml is optimal for obtaining the best results.

The DynaPro Titan analyzes the time scale of the scattered light intensity fluctuations by a mathematical process called autocorrelation. To perform the fast data manipulation necessary to obtain results in real time, the DynaPro Titan uses the correlator running special algorithms. The translational diffusion coefficient of the molecules in the sample is determined from the decay of the intensity autocorrelation data. The hydrodynamic radius of the sample is then derived from the translational diffusion coefficient and the weight-average molar mass is calculated.