Zeta potential analysis

K Thode, RH Muller, M Kresse. Two-time window and multiangle photon correlation spectroscopy size and zeta potential analysis—highly sensitive rapid assay for dispersion stability. J Pharm Sci 89 1317-1324, 2000. 

The membranes were then measured with the separate background solution components and the electrolyte, commonly used for zeta potential analysis, 1 mM KCl. Results are shown in Figure 7.5, Figure 7.6, Figure 7.7, and Figure 7.8 for the TFC-SR, TFC-S, TFC-ULP, and CA-UF membranes, respectively. 

Aggregation studies, using SEM, DLS, and zeta potential analysis, indicate that severe aggregation between amine-modified silica nanoparticles can be reduced by adding inert functional groups, such as methyl phosphonate, to the surface... 

The surface of FW200 carbon black exhibited an electron acceptor (acidic) characteristics. On the other hand, the N550 showed electron donor (basic) character which was reflected by the zeta potential analysis. The addition of dispersing agents changed the character of filler s surface as shown in Figure 3. 

Zeta potential analysis of fillers dispersed in water. The surface of N550 and Printex carbon black exhibited an electron donor (basic) characteristics. The isoelectric point for semi-active black and conductive occurred at respectively pH=9,5, pH=10,5. On the other hand the FW200 carbon black showed electron acceptor (acidic) characteristics in whole pH measuring range. 

When blackberries are formed, most of the counterions are found to be absorbed around them. POM blackberries exist in solution as large, highly charged species. To determine the charge carried by the macroions and the blackberries, zeta potential analysis has been applied. Zeta potential analysis is a measurement of the electrical potential that exists at the surface of a charged particle in solution. To determine the charge of the POM blackberries, the ion mobility must be... 

Abstract Two systems are discussed in this chapter, which are copper activating zinc-iron system with and without depressants. Firstly, the system in the absence of depressants is discussed. And it is obtained that at a specific pH the activation for each mineral occurs in a certain range. Through the electrochemical methods and surface analysis the entity contributing to the activation can be identified which are usually copper sulphides and vary for different minerals. Secondly, the system with depressants is researched. And also the effects of pulp potential on the activation are discussed. The same conclusion can be obtained as the one from the former system. Furthermore, zeta potential are involved in the discussion of activation and die mechanism can be explained firom the changes of zeta potential. Similarly, the activation mechanism of this system is also studied through solution chemistry, bonding of activator with mineral surfaces and surface analysis. 

The obtained STPP liposomes were characterized by size distribution analysis, P NMR spectroscopy (Fig. 3), and by zeta potential measurements (Fig. 4). The size of liposomes with 20 mol% incorporated STPP was determined to be 132 zb 59 nm, which did not change significantly upon storage at 4°C over several days. The P NMR spectrum of STPP liposomes shows two chemical shifts correlating to the phosphorus in the lipid s phosphate groups and to the positively charged phosphorus of STPP. No differences in both chemical shifts between the free compounds (i.e., free STPP and free... 

The amount of polymer adsorbed on each sample was measured by pressure filtration through a 0.1 m filter, followed by analysis of the filtrate for residual polymer by gel permeation chromatography with refractive index determination. Particle zeta potentials were measured by taking a small sample of the solids from the centrifuge and re-suspending them in the supernatant prior to analysis in a Malvern Instruments Zetasizer . The concentration of all other types of ions in the supernatant was analysed by ICP atomic emission spectroscopy. 

A corrected and more general analysis of the primary electroviscous effect for weak flows, i.e., for low Pe numbers (for small distortions of the diffuse double layer), and for small zeta potentials, i.e., f < 25 mV, was carried out by Booth in 1950. The result of the analysis leads to the following result for the intrinsic viscosity [rj] for charged particles in a 1 1 electrolyte ... 

Fig. 25 Characterization and luciferase expression of PGP DNA condensates in vivo. These results show that luciferase expression is dependent on galactose incorporation but independent of amount of melittin. (a) Represents the input mol ratio of Cys-terminated melittin, PEG-peptide, and glycopeptide. (b) Represents the measured mol ratio of Cys-terminated melittin, PEG-peptide, and glycopeptide for each purified PGP. (c) Values are the calculated MW based on polylysine standards, (d) Values are the calculated MW based on PEG standards, (e) The mean particle size determined at a stoichiometry of 0.3 nmol of PGP per mg of DNA. The value represents the mean diameter (nm) based on unimodal analysis, (f) The zeta potential of PGP DNA condensates at a stoichiometry of 0.3 nmol of PGP per mg of DNA. (g) The metabolic half-life of PGP 125I-DNA in triplicate mice. The results are derived from Fig. 6. (h) The PC/NPC ratio of DNA-targeted liver, (i) Represents a control PGP 3 in which galactose has been removed. Figure adapted with permission from [182], 2007 American Chemical Society...

Concentration profiles were derived by gray-scale analysis from the images mentioned above [92], Whereas without use of zeta potential variation no difference in concentration profiles between the upstream and downstream positions is visible, a much more flattened, i.e. mixed, profile results under electrokinetically driven conditions in the downstream position. 

Direct control of the EOF in capillary zone electrophoresis can be obtained by using an external electric field. The EOF may be increased, decreased, or even reversed in the fused silica capillaries by the application of a separate potential field across the wall of the capillary. Further, the zeta potential can be changed at any time during the analysis to achieve innovative separation results. 

There have been quite a few studies on electrophoresis of a particle in this regime. The first analysis which takes into account the finite thickness of the ion cloud was conducted by Henry [9]. He investigated the electrophoresis of a sphere of radius a with small uniform zeta potential ( for the entire range of m. With an assumption of small applied electric field, the charge density and the electrical potential can be written as their equilibrium values plus... 

Ennis and White [56] employed the method of reflections to investigate the electrophoresis of two spherical particles with equilibrium double layers of arbitrary thickness. Their analysis assumes that the zeta potential of the particle is small and the double layers do not overlap significantly. One interesting finding from their study is that the particles with equal zeta potential do interact with each other when the double layer thickness is finite, unlike the no-interaction result for the case of infinitely thin ion cloud. The leading order interaction between two particles is still but the... 

Dispersion technologies, USA (http //www. dispersion, com/) Felix Alba Associates (Scatterer.com) Scatterer Electro-acoustic spectroscopy Data interpretation software Particle sizing, zeta potential Particle size analysis No Yes... 

A detailed analysis of the theories of electroosmotic flow in porous media was presented earlier [22] of the theories by Overbeek [23-25] and Dukhin and his co-workers [26-30], Overbeek extended von Smoluchowski s work to packed capillaries under conditions of low electric field strength. The model can be applied to porous or nonporous packing particles of any shape, and the particles can be assumed to be nonconducting, have uniform zeta potential, and a thin double layer. The average EOF velocity in a column for CEC can be expressed as... 

The size and charge analysis was done using a Coulter DELSA 440SX (Coulter Beckman Corp., Miami, FL). This particular instrument measured the size distribution on the basis of photon correlation spectrometry (PCS) and was limited to particle diameters between 0.02 pm and 3 pm. Measurements were taken at four different angles simultaneously with 256-channel resolution each. Comparison of the spectra allowed for the detection of very small particles. The zeta potential was assessed on the basis of electrophoretic mobility (laser Doppler anemometry, LDA). This was defined as the particle velocity per unit of applied electrical field, with units usually given as pm s 1/V cm-1, while zeta potential is defined as the electrical potential between the bulk solution and the... 

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