Light scattering analysis

Shen CL, Scott GL, Merchant F, Murphy RM. Light scattering analysis of fibril growth from the amino-terminal fragment beta(l-28) of beta-amyloid peptide. Biophys J 1993 65 2383-2395. 

Brown, W. 1996. Light Scattering Principles and Development. Oxford University Press, New York. Debye, P.J. 1944. Light scattering analysis. J. Appl. Phys., 15 338. 

Habel, J. E., Ohren, J. R and Borgstahl, G. E. (2001). Dynamic light-scattering analysis of full-length human RPA14/32 dimer purification, crystallization and selfassociation. Acta Crystallogr. D 57, 254-259. 

An independent x-ray and light scattering analysis (see Section 5.6a and Example 5.4) of a dispersion of the aggregates suggests that the aggregates have a fractal structure with a fractal dimension of 2.65. Is this confirmed by your result ... 

Figure 1. Computer plot of the light-scattering analysis of HEC before enaocellulase hydrolysis. (O) Experimental Kc/R values, (M) extrapolated values (by quadratic least squares analysis). The inverse of the Kc/Re intercept, Mw, equals 1,285,000.

Figure 2. Computer plot of the light-scattering analysis of HEC after endocellulase attach (O) Experimental Kc/Re values, extrapolated...

An indication of the validity of the extrapolation method could be given by light-scattering analysis of an intermediate-molecular-weight hydrolysate due to a very low cellulase activity. Indeed, at a relatively high HEC concentration of 3.152 X 10 3 g/mL, a limo-o Kc/Re value of... 

Example. A tailings stream from the hot-water flotation process (oil sands) contains 27 % (mass) solids. Estimate the suspension viscosity. Light-scattering analysis indicates that the particles are finely divided and anisotropic with a 10 Tm major dimension and a 0.5 pm minor dimension. Using Eq. 

Oja, T. Bott, S. Sugrue, S. Doppler electrophoretic light scattering analysis using the coulter DELSA 440. Coulter Electronics Luton, 1989. 

The authors would like to acknowledge Dr. Gorgon Chiu from Phase Technology (Richmond, B.C., Canada) for the light-scattering analysis. 

Some light scattering measurements require knowledge of a particle s optical properties. The light scattering analysis uses these optical properties in a model for the calculation of particle size, and for accurate results you need to choose a model that best represents these optical properties. Picking an improper model will yield inaccurate results. Microscopy only requires a small amount of material and can be used to quickly measure these optical properties. 

Protein content, particularly in urine or cerebrospinal fluid, may also be estimated by methods based on precipitation using sulfosalicylic acid (an anionic protein precipitant) or heat. The turbidity, which is a measure of protein concentration, can be quantitated by spectropho-tometric absorbance methods or light scattering analysis. Absorbance of a hydrophobic indicator dye that binds to protein and changes color is also used. 

Figure 4. Apparent distributions of equivalent Stokes diameters, from quasi-elastic light scattering analysis of mixtures of 1.0 g/L PDMDAAC and 6.7 g/L BSA, in 0.01 M NaOAc buffer, at pH values shown.

Yamamoto, T. et al., Extensive studies on Jt-stacking of poly(3-alkylthiophene-2,5-diyl)s and poly (4-alky lthiazole-2,5-diyl)s by optical spectroscopy, NMR analysis, light scattering analysis, and x-ray crystallography, J. Am. Chem. Soc. 120, 2047-2058, 1998. 

Moradian-Oldak. J. Leung, W. Fincham, A.C. Temperature and pH-dependent supramolecular self-assembly of amelogenin molecule A dynamic light scattering analysis. J. Struct. Biol. 1998. 122. 320-327. 

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