Electrophoretic mobility chloride

It is interesting to compare these results with the electrophoretic measurements made under identical electrolyte concentrations. Figure 8 shows that the variation of electrophoretic mobility with sodium chloride concentration is different for the bare and the PVA-covered particles. For the bare particles, the mobility remains constant up to a certain salt concentration, then increases to a maximum and decreases sharply, finally approaching zero. The maximum in electrophoretic mobility-electrolyte concentration curve with bare particles has been explained earlier (21) by postulating the adsorption of chloride ions on hydrophobic polystyrene particles. In contrast, for the PVA-covered particles, the mobility decreases with increasing electrolyte concentration until it approaches zero at high salt concentration. 

Figure 26-31 Separation of natural isotopes of 0.56 mM Cl by capillary electrophoresis with indirect spectrophotometrlc detection at 254 nm. Background electrolyte contains 5 mM CrOJ to provide absorbance at 254 nm and 2 mM borate buffer, pH 9.2. The capillary had a diameter of 75 m, a total length of 47 cm (length to detector = 40 cm), and an applied voltage of 20 kV. The difference in electrophoretic mobility of 36C and 37CI is just 0.12%. Conditions were adjusted so that electroosmotlc flow was nearly equal to and opposite electrophoretic flow. The resulting near-zero net velocity gave the two isotopes maximum time to be separated by their slightly different mobilties. [From C. A Lucy and T. L McDonald, "Separation of Chloride Isotopes by Capillary 35 40 45 Electrophoresis Based on the Isotope Effect on Ion Mobility"Anal.

Now, when the ionic front reaches the lower gel with pH 8 to 9 buffer, the glycinate concentration increases and anionic glycine and chloride carry most of the current. The protein or nucleic acid sample molecules, now in a narrow band, encounter both an increase in pH and a decrease in pore size. The increase in pH would, of course, tend to increase electrophoretic mobility, but the smaller pores decrease mobility. The relative rate of movement of anions in the lower gel is chloride > glycinate > protein or nucleic acid sample. The separation of sample components in the resolving gel occurs as described in an earlier section on gel electrophoresis. Each component has a unique charge/mass ratio and a discrete size and shape, which directly influence its mobility. 

In the case of high-mobility analytes such as inorganic anions,, e values are comparable or even greater than that of xe0. For instance, common anions such as chloride, bromide, and sulfate have electrophoretic mobilities of 7.92, 8.09, and 8.29 x 1CT4 cm2/(V s), respectively. Thus, these anions migrate faster than the EOF but in the opposite direction. As a consequence, they would not be detected in the normal configuration described above (detector at cathode). Rather one would need to inject at the cathode and place the detector at the anode to detect these ions. 

The soluble protein showed a single boundary peak in the Tiselius apparatus in buffers of ionic strength 0.02 at all pH values in the range pH 2-9, but its isoelectric point was markedly dependent upon the salt concentration. At ionic strength 0.2, in the presence of sodium chloride, the isoelectric point both from electrophoretic mobility measurements and membrane potential determinations was pH 3.9-4,0. At lower ionic strength (0.02) the protein was isoelectric at pH 4.8 in the electrophoresis experiments and pH 4.7 in membrane potential determinations. 

Figure 10.6. Plots of electrophoretic mobility and current against the concentration of the salte. (A) sodium chloride, and (B) lithium sulfate. Ions (top to bottom) Br", NO2. n 4, ...

Figure 10.6 shows that the greatest differences between electrophoretic mobilities and electroosmotic mobility occur around 200 mM salt in the BGE. Figure 10.7 shows an excellent separation of inorganic anions at pH 8.5 in 220 niM sodium chloride. The high salt concentration suppresses the EOF sufficiently that no flow modifier is... 

The equilibrium properties of foam films formed from aqueous solutions of decylmethyl sulfoxide have been studied in the presence of sodium chloride and potassium thiocyanate. Stable films were formed whose thicknesses depended on the electrolyte concentration. As the electrolyte concentration was increased, a sudden increase in film thickness occurred but gradually decreased with further electrolyte addition. Examination of the electrophoretic mobility of dodecane droplets stabilized by decylmethyl sulfoxide showed an increase in mobility at about the same concentration. These data indicated that the thicker foam films were charge stabilized owing to the adsorption of the anions. The surface pressures and surface potentials of monolayers of octadecyl sulfoxide were also investigated. 

A systematic study of the influence of salts on foam films formed from nonionic surface active agents was carried out in these laboratories (3, 6). This paper reports an investigation of the effects of sodium chloride and potassium thiocyanate on the thickness of foam films formed from DMS. In addition to measurements on films, the electrophoretic mobilities of dodecane droplets stabilized with DMS were determined as a function of salt concentration, and the properties of insoluble mono-layers of octadecylmethyl sulfoxide (OMS) at the air-water interface have been examined using the classical methods largely developed by N. K. Adam (7). 

Electrophoretic Mobility. To estimate the possible charge on the sulfoxide film surface, we investigated the effects of sodium chloride and potassium thiocyanate on the electrophoretic mobility of dodecane droplets stabilized with DMS (see Figure 4). In the sodium chloride system the droplets were essentially uncharged at low concentrations, but between 3-5 X 10"3 mole/dm3, the mobility increased to —1.2 mfx cm/V sec. In the potassium thiocyanate system, the droplets had a mobility of... 

Figure 4. Electrophoretic mobility vs. log. Molar concentration of electrolyte for DMS stabilized dodecane droplets ( ) in sodium chloride solutions, (O) in potassium thiocyanate solutions.

Figure 13 exhibits both interfacial tension and electrophoretic mobility for the Huntington Beach Field crude oil against sodium orthosilicate containing no sodium chloride. The interfacial tension values are observed to be higher for the non-equilibrated sample in this case than for the caustic system reported in Figure 12. The minimum interfacial tension of 0.01 dynes/cm occurs at about 0.2% sodium silicate as opposed to a value of less than 0.002 dyne/cm at about 0.06% NaOH. It is interesting to note, however, that the maximum electrophoretic mobility is the same for the two systems. Once again, it should be noted that a maximum in electrophoretic mobility does not correspond to a minimum in interfacial tension for those samples which contained no sodium chloride.

CE CGE CHOL CIP CPG CTAB CZE dA, dG, dC DBU DEAE DMF DMT DNP DOPE DOTMA EDTA EM EOF ESI-MS Fmoc FPE ICAM-1 Capillary electrophoresis Capillary gel electrophoresis Cholesterol Cahn-Ingold-Prelog nomenclature system for absolute configuration Controlled pore glass Hexadecyltrimethylammonium bromide Capillary zone electrophoresis Deoxyadenosine, deoxyguanosine, deoxycytosine l,8-Diazabicyc o[5.4.0]undec-7-en Diethylaminoethyl- Dimethylformamide Bis(4-methoxyphenyl)phenylmethyl-, (syn. Dimethoxytrityl-) 2,4-DinitrophenyI- Dioleylphosphatidylethanolamine N-[l-(2,3-dioleyloxy)propyl]-N, N, N-trimethylammonium chloride Ethylenediamine tetra-acetic acid Electrophoretic mobility Electro-osmotic flow Electrospray ionization mass spectrometry 9-Fluorenylmethoxycarbonyl-Fluid phase endocytosis Intracellular Adhesion Molecule-1... 

Fig. 17. Electrophoretic mobility—pH curve of L-myosin in varying concentrations of calcium and magnesium chlorides (0.03 — 0.24 M). O < 0.1 M salt A > 0.1 M. salt (after Erdos and Snellman, 1948).

Figure 4. Electrophoretic mobility of calcium oxalate with 0.1 g/1 macromolecule for various calcium chloride or sodium oxalate additions. The numbers near the data points are solution pH.

Kaneta T,Tanaka S, Taga M. (1993). Effect of cetyltrimethylammonium chloride on electro-osmotic and electrophoretic mobilities in capillary zone electrophoresis. Journal of Chromatography A 653(2) 313-319. 

Light transmission L. L. Schramm and J.C.T. Kwak, op. cit. Electrophoretic mobility P. Bar-On, I. Shainberg, and I. Michaeli, Electrophoretic mobility of montmorillonite particles saturated with Na/Ca ions, J. Colloid Interface Sci. 33 471 (1970). Intrinsic viscosity I. Shainberg and H. Otoh, op. cit. Chloride exclusion volume J. E. Dufey, A. Banin, H. G. Laudelout, juid Y. Chen, Particle shape and sodium self-diffusion coefficient in mixed sodium-calcium montmorillonite. Soil Sci. Soc. Am. J. 40 310 (1976). 

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