Combination of Static and Dynamic Light Scattering

Fig. 9 Density profiles of PEE-PSSH micelles for varying salt concentrations. The profiles were obtained by a combination of static and dynamic light scattering, small-angle neutron scattering and cryo-TEM [49]...

E. Osmotic swelling of living cells by combination of static and dynamic light scattering... 

E. Osmotic Swelling of Living Cells by Combination of Static and Dynamic Light Scattering... 

With regard to the polydispersity these quantities show a behavior opposite to that of the scattering functions. While the curves of Pz(q) become flatter with rising polydispersity, the angular dependence of Rl , p(q) increases (see [80]). Therefore the combination of static and dynamic light scattering provides reliable information about the polydispersity of the systems under study. Additional information on the polydispersity comes from the second cumulant and the inverse Laplace transform. 

The experimental techniques for the study of conformational branched properties in solution are the same as used for linear chains. These are, in particular, static and dynamic light scattering, small angle X-ray (SAXS) and small angle neutron (SANS) scattering methods, and common capillary viscometry. These methods are supported by osmotic pressure measurements and, nowadays extensively applied, size exclusion chromatography (SEC) in on-line combination with several detectors. These measurements result in a list of molecular parameters which are given in Table 1. 

Figure 6.2 Effect of sucrose on the self-assembly / disassembly of sodium caseinate in aqueous medium (ionic strength = 0.01 mol/diu3, 22 °C) on the basis of combined static and dynamic light scattering. Upper plots refer to pH > pI, i.e.. ( ) pH = 7.0, ( ) pH = 6.0, (A) pH = 5.5 (a) weight-average molar weight, A/w (b) structure-sensitive parameter p. Lower plots refer to pH < p/, i.e., ( ) pH = 3.9, (A) pH = 3.5 (c) weight-average molar weight, A/w (d) structure-sensitive parameter p.

Combination of static and dynamic laser light scattering is also useful to determine not only the size distribution but also the particle structure of polymer colloids such as the adsorbed surfactant layer thickness [73] and the formation of nanoparticles [74,75]. A recently developed method of determining the density of polymer particles is outlined below to illustrate the usefulness of laser light scattering as a powerful analytical tool for investigating more sophisticated colloidal problems [76-78]. 

In [93-95] a combination of turbidimetry and static and dynamic light scattering was applied to study the structure of complexes between PDADMAC samples of different molecular weights and charged mixed micelles. A review on such studies of polyelectrolyte-protein complexes is given in [96]. 

In the present study, we have performed rheological measurements on the C16E7/D2O system in addition to static and dynamic light scattering. Combining these results with the relaxation time obtained from the slow mode of dynamic light scattering [16-18] and the surfactant self-diHusion coefficient [21-23] reported previously, dynamics of worm-like micelles is discussed in more detail than in our previous study. 

Static and dynamic light scattering as well as electron microscopy were used for structural investigations. By a combination of these methods one may determine the mass, the radius of gyration, the hydrodynamic radius and the polydispersity of a particle system. By a comparison of the results obtained for the original and the polymer covered latex the structural parameters of the polymer layer can be assessed. Ultracentrifugation was used for latex separation. A subsequent determination of the polycation concentration via PEC-formation in the supernatant yields exact information on the amount of polycation, which was bound on the latex. 

All the gel moduli can be defined by a combination of the static and dynamic light scattering methods. 

The particle concentration of the eluent is normally measured by means of infrared or ultraviolet photometers. Additionally, fluorescence photometer, interferometric measurements (for the refractive index), or mass-spectroscopic methods (e.g. induced coupled plasma mass spectroscopy—ICP-MS, Plathe et al. 2010) are employed. The combination of different detection systems offers an opportunity for a detailed characterisation of multi-component particle systems. Note that the classification by FFF is not ideal and the relevant material properties are not always known moreover, the calibration of FFF is rather difficult. The attribution of particle size to residence time, thus, bears some degree of uncertainty. Recent developments of FFF instrumentation, therefore, include a particle-sizing technique additional to the flow channel and the quantity measurement (usually static and dynamic light scattering, Wyatt 1998 Cho and Hackley 2010). 

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