Centrifugation analytical

Many different mechanical arrangements have been used in the construction of rotors for centrifugation. For analytical centrifugation, these rotors must be designed to overcome the problem of convection and to make it possible to detect the component zones which are normally hard to track... 

The object of this study was to clarify some aspects of the mechanism of shear-induced flocculation in colloidal dispersions. Vinyl chloride homopolymer and copolymer latices were prepared by emulsion polymerization using sodium dodecyl sulphate as emulsifier. Agglomeration behavior in these latices was studied by measuring the mechanical stability using a high speed stirring test. The latex particle size was measured by an analytical centrifuge. Molecular areas of emulsifier in the saturated adsorption layer at the surface of homopolymer and copolymer latex particles were estimated from adsorption titration data. 

Characterization of particle size. In Figure 12. a comparison is given between particle size determination by the analytical centrifuge, by electron microscope and by nitrogen adsorption on the carefully... 

Figure 13. Histogram particle size distribution obtained by electron microscopy. Curve the normal distribution with mean 1530 and standard deviation 340. Analytical centrifuge I960 A.

Figure 14. Dp measured by analytical centrifuge. Em determined by soap titration. Estimation of Am from these data.

The area occupied by each adsorbed emulsifier molecule at the polymer-water interface (A ) was estimated from the mean particle size of the latices, determined by the analytical centrifuge, and the amount of emulsifier adsorbed at the interface corresponding to full coverage, determined by adsorption titration. 

Cole, J. L. (1996) Characterization of human cytomegalovirus protease dimer-isation by analytical centrifugation. Biochemistry 35, 15,601-15,610. 

Figure 33. Principle of an analytical centrifugal sifter (Fritsch Analysette 9)...

Analytical centrifugation is a method of studying the hydrodynamic properties of a molecule as it moves through a fluid medium. Hydrodynamic behavior depends on mass, density, and shape, so one can study these properties of a molecule by accelerating... 

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