Zeta potential aggregation

Eleetrostatie eharaeterization of partieles is eommonly determined via their eleetrokinetie or zeta potential i.e. the potential of a slipping plane, notionally loeated slightly away from the partiele surfaee approximately at the beginning of the diffuse part of the double layer using, for example, eleetrophoresis. In some eases, zeta potential ean be used as a eriterion for aggregation. 

Numerous studies reported the in vitro interaction of lipoplexes with serum (14). The parameters checked, such as maintained lipid-DNA interactions, aggregate formation, zeta potential changes, or DNA morphological changes, did not allow for consistent prediction of in vitro transfection efficiency of lipoplexes in serum (15). However, it is obviously an indication of poor delivery of DNA at the target site. 

As described above, lipoplex PEGylation limits the formation of aggregates and zeta potential changes in serum. 

Initially, this mechanism was proposed on the basis of results obtained for zeta potential and flotation (Fig. 29). The formation of the hydrophobic aggregates at the interface was confirmed after the advent of the fluorescence probing technique. The adsorption isotherm is determined in the presence of pyrene as the fluorescent probe and the emission spectra of pyrene in both supernatant and slurries were analyzed after adsorption. The h/h of pyrene in solutions of SDS containing 0.1 M NaCl and in the slurry are shown in Figs. 30 and 31. In solution, the ratio remains at around 0.6 till the CMC (as determined by surface tension measurement) is attained. Above CMC, the value becomes 1.0 due to the solubilization of pyrene in micelles. In... 

Fig. 32 Schematic representation of the correlation of surface charge and growth of the aggregates for the various regions of the adsorption isotherm of SDS on alumina based on fluorescence data and zeta potential measurement...

Kamo et al. [Biochim. Biophys. Acta, 367, 1 and 11 (1974)] have shown that nonionic sugars modify the zeta potential of slime mold cells. Aggregation of colloids is related to their surface charge and their surface potential. This fact shows evidence of long-range electrostatic interactions controlled by metabolic reactions taking place at the membrane and able to modify the composition of the membrane medium interface. In this process the diffusion is not relevant, as indicated by Mrs. Babloyantz. 

Sejersen, M.T., Salomonsen, T., Ipsen, R., Clark, R., Rolin, C., Engelsen, S.B. (2007). Zeta potential of pectin-stabilized casein aggregates in acidified milk drinks. International Dairy Journal, 17, 302-307. 

The aggregation number rt and radius of sodium dodecyl sulfate micelles (by light scattering) and the zeta potential (from electrophoresis, by an accurate formula) were determined in the presence of various concentrations of NaCl. ... 

Fig. 22 Size (a) and zeta potential (b) of EDOPC/DNA lipoplexes at different lipid/ DNA ratios [69] as is known, lipoplex aggregation taking place at the isoelectric point results in lipoplex size growth [70]...

The surface charge of nanoparticles is important because it determines the nature and extent of aggregation of colloids and their interaction with cells and other biological components within the body. The zeta potential is the potential at the solid-liquid interface and is commonly determined using light scattering [153], Decreasing the zeta potential of nanoparticles below a critical value increases the rate and... 

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