Light scattering mixed micelles

Y. Li, J. Xia, and P.L. Dubin Complex Formation Between Polyelectrolyte and Oppositely Charged Mixed Micelles Static and Dynamic Light Scattering. Study of the Effect of Polyelectrolyte Molecular Weight and Concentration. Macromolecules 27, 7049 (1994). 

NA Mazer, GB Benedeck, MC Carey. Quasielastic light-scattering studies of aqueous biliary lipid systems. Mixed micelles formation in bile salt-lecithin solutions. Biochemistry 19 601-615, 1980. 

Several papers compare the properties of sulfobetaine (meth)acrylic polymers. NMR spectra and solution properties of 23a and 23b [59,60] are correlated with data from the corresponding polycarbobetaines [26]. The photophysical and solution properties of pyrene-labeled 23c were studied in terms of fluorescence emission. Addition of surfactants induces the formation of mixed micelles in aqueous solution [61]. Excluded volume effects of the unlabeled polymer were measured by light scattering [62], its adsorption on silica was studied by adsorbance measurement and ellipsometry [62,63], and the electrostimulated shift of the precipitation temperature was followed at various electric held intensities [64]. Polysulfobetaines may accelerate interionic reactions, e.g., oxidation of ferrocyanide by persulfate [65]. The thermal and dielectric properties of polysulfobetaines 23d were investigated. The flexible lateral chain of the polymers decreased Tg, for which a linear relationship with the number of C atoms was shown [66,67]. 

Schematic models for the expanded structure of bile acid-phosphatidylcholine mixed micelles are shown in Fig. 2B. The original model was proposed by Small in 1967 (S36). In this model the mixed micelle consisted of a phospholipid bilayer disk surrounded on its perimeter by bile acid molecules, which were oriented with their hydrophilic surhices in contact with aqueous solvent and their hydrophobic sur ces interacting with the hydrocarbon chains of the phosphohpid molecules. This model has recently been revised, based on further studies of mixed micelles using quasi-elastic light scattering spectroscopy (M20). In a new model for the molecular structure of bile acid-phospholipid mixed micelles. Mazer et al. (M20) propose a mixed disk, in which bile acids are found not only on the perimeter of phospholipid bilayers, but also incorporated within their interior in high concentrations (Fig. 2B). The size of these mixed micelles was estimated to be as high as 200 to 400 A in radius in some solutions, and disk-shaped particles in this size range were observed by transmission electron microscopy (M20). Micellar aggregates similar in size and structure to those found in model bile solutions have been demonstrated in dog bile (M22).

Light scattering methods (often in combination with other experimental methods) are widely used for the investigation of complex surfactant systems such as mixed micelles, " block... 

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]. 

Li Y, Xia J, Dubin PL. Complex-formation between polyelectrolyte and oppositely charged mixed micelles—static and dynamic light-scattering study of the effect of polyelectrolyte molecular-weight and concentration. Macromolecules 1994 27 7049-7055. 

Li Y, Dubin PL, Havel HA, Edwards SH, Dautzenberg H. Electrophoretic light-scattering, dynamic light-scattering, and turbidimetry studies of the effect of polymer concentration on complex-formation between polyelectrolyte and oppositely charged mixed micelles. Macromolecules 1995 28 3098-3102. 

In works, " the catalytic effect of the CTAB and PM reverse micelles on the reaction of pyrimidinophanes (PPh) (Scheme 15.2) and their acyclic analogue A,A -bis(2-methylthio)-6-methylpyrimidin-4-yl)hexamethylenediamine with phosphinate 12 in chloroform is studied. The formation of the CTAB—PM mixed aggregates is proved by the NMR self-diffusion, by dielcometric titration, and by dynamic light scattering. " The micellar catalytic effect is shown to change with the size of macrocycle in the series PPh-4 < PPh-3 < PPh-2 < PPh-1. The maximum acceleration of the reaction observed at a 5 1 CTAB/PM molar ratio exceeds five orders of magnitude. 

Earlier the interrelation between the influence of MR concentration on nonspecific activity of lysoz5mie and the destabilizing effect of MR on its native conformation were established. It is shown, that activity and thermostability of lysozyme depend on the concentration of MR and the incubation time of their mixed solutions [2]. The MR ability to self-orga-nization in a solution with micelle like structure formation was established via methods of mixing microcalorimetry and dynamic light scattering [3]. 

BaUlet S, Grassl B, Desbrieres J. Rapid and quantitative determination of critical micelle concentration by automatic continuous mixing and static light scattering. Anal Chim Acta 2009 636 236-241. 

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