Vesicles sizes

Abra, R. M., and Hunt, C. A. (1981). Liposome disposition in vivo, III. Dose and vesicle size effects, Biochim. Biophys. Acta, 666, 493-503. 

Ueno, M., Tanford, C., and Reynolds, J. A. (1984). Phospholipid vesicle formation using nonionic detergents with low monomer solubility. Kinetic factors determine vesicle size and polydis-persity. Biochemistry, 3070-3076. 

Milon, A., T. Lazrak, A. M. Albrecht et al. 1986. Osmotic swelling of unilamellar vesicles by the stopped-flow light scattering method. Influence of vesicle size, solute, temperature, cholesterol and three a, Q)-dihydroxycarotenoids. Biochim. Biophys. Acta 859 1-9. 

Talsma [1.34] showed with phospholipon 100 H, a hydrated phosphatidyl-choline of soya beans, (Nattermann, Cologne) and dicetylphosphate (DCP) (molar ratio 10 1) from which bilayer liposomes have been produced, the influence of one CPA (I), of several CPAs (II), of the vesicle size (III), and the cooling rate (IV). In all of the following tests Tris buffer of pH 7.4 is used. 

Mayer LD, Tai LC, Ko DS, et al. Influence of vesicle size, lipid composition, and drug-to-lipid ratio on the biological activity of liposomal doxorubicin in mice. Cancer Res 1989 49 5922. 

Entrapment value was obtained by the dehydration-rehydration method carried out in the presence of sucrose (see text). z-Average vesicle size... 

The content of vaccine within the small liposomes is estimated as in the section Estimation of Vaccine Entrapment in Dehydration-Rehydration Vesicles Liposomes for both microfluidized and sucrose liposomes and expressed as percentage of DNA and/or protein in the mixture subjected to freeze drying as in the section Preparation of Vaccine-Containing Small Liposomes by the Sucrose Method in the case of sucrose small liposomes or in the original DRV preparation (obtained in the section Estimation of Vaccine Entrapment in DRV Liposomes ) for microfluidized liposomes. Vesicle size measurements are carried out by PCS as described elsewhere (6,8,17). Liposomes can also be subjected to microelectrophoresis in a Zetasizer to determine their zeta potential. This is often required to determine the net surface charge of DNA-containing cationic liposomes. 

Tilcock, C., Ahkong, Q. R, Koenig, S. H., Brown 3rd, R. D., Davis, M., and Ka-balka, G. The design of liposomal paramagnetic MR agents Effect of vesicle size npon the relaxivity of surface-incorporated lipophilic chelates. Magn. Res. Med. 1992, 27, 44-51. 

Determination of Vesicle Size by Laser Light Scattering... 

The vesicle size is an important parameter not only for in-process control but particularly in quality assurance, because the physical stability of the vesicle dispersion depends on particle size and particle size distribution. An appropriate and particularly quick method is laser light scattering or diffraction. Laser light diffraction can be applied to particles > 1 pm and refers to the proportionality between the intensity of diffraction and the square of the particle diameter according to the diffraction theory of Fraunhofer. 

Vesicle size, bilayer fluidity, membrane permeability, microviscosity, ability to bind small molecules, suseeptibility to pore formation, flip-flop rates, extent of water penetration, lateral amphiphile diffusion, vesiele fusion, and kinetic medium effeets (some of which will be discussed briefly below) all depend on the paeking of... 

Vesicle size was found to affect reaction kinetics for the alkaline hydrolysis and thiolysis of p-nitrophenyl octanoate, with small vesicles being more effective as catalysts, and it was concluded that this size dependence itself was brought about by differences in ion dissociation, substrate binding constants, and intrinsic reactiv-... 

Peek BM, Callahan JH, Namboodiri K, Singh A, Gaber BP. Effect of vesicle size on the pol5fmerization of a diacetylene lipid. Macromolecules 1994 27 292-297. 

The vesicular size might go back reversiblly to the original one in the case of nonionic vesicles (Figures 9 and 10) for which the present removal rate may be too slow. A similar behavior was reported by Schurtenberger et al. for their lecithin-bile salt systems vesicle size is reduced to the original dimension after dialysis of remains large when the solubilized is diluted with the buffer solution to very fast reduction of bile salt fast removal of bile salt(22) ... 

One way is to label the pre-existing vesicles, and then follow the destiny of the label in the vesicle size distribution. The label that has been used to this aim is ferritin, which has been entrapped into vesicles. Ferritin is an iron-storage protein in plants and mammals, and consists of a hollow protein shell of c. 12 nm containing... 

Figure 10.22 Vesicle size selection by RNA added to a mixture of small ( 80 nm diameter) and large vesicles ( 160 nm) from 0.5 mM POPC-3.5% CTAB in 20 mM sodium phosphate buffer (pH 7.0). (a) The initial size distribution of the 1 1 mixture (b) the size distribution 4 min after RNA addition, during the selection process (c) the stable final size distribution after 15 min, with one peak for small diameters ( 90 nm) and a second peak indicating aggregates of large vesicles (> 1000 nm). As mentioned in the text, this process is reversible upon addition of RNAase (Thomas and Luisi, 2004.)...

Single-compartment DHP vesicles Size-quantized CdS particles generated in situ in vesicles... 

Li, Y.P. and Mitra, A.K., (1996). Effects of phospholipid chain length, concentration, charge, and vesicle size on pulmonary insulin absorption. Pharmaceut. Res., 13, 76-79. 

The results in Figure 2 indicate that the degree of aggregation increases with Na+ concentration. However, at present, the measurements may not yield half-life times (or shorter times for the dimerization reaction) mainly because initially we had a heterogeneous distribution of vesicle sizes. What we actually see might reflect an advanced stage in... 

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