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What is the formula for electrophoretic mobility?

What is the formula for electrophoretic mobility?

The apparent free electrophoretic mobility can be obtained by applying eqn [25] ( μ ( mm s − 1 ) = h × T max δ ) . The free electrophoretic mobilities of various marker proteins and five different mammalian carbonic anhydrases calculated by these procedures are listed in Table 6.

How do you calculate electroosmotic flow rate?

For example, if we apply 300 V along a 1-cm-long microchannel of r = 50 μm, the electro-osmotic velocity will be uEOF = 2.13 mm/s and the corresponding volumetric flow rate will be Q = 1 μL/min, when ε = 7.1 × 10–10 F/m, ζ0 = -0.1 V, and μ = 0.001 N s/m2.

What is the difference between electrophoretic mobility and electroosmotic flow?

Mobility is proportional to the q/r ratio (q = charge and r = solute size). Solvated cations drag water molecules during the migration, hence there is net solution movement from anode toward cathode. Electroosmotic flow results because of the electric double layer than forms near the capillary wall.

How is electroosmotic flow generated?

Electroosmotic flow is caused by the Coulomb force induced by an electric field on net mobile electric charge in a solution. The resulting flow is termed electroosmotic flow.

Who has highest electrophoretic mobility?

Among the three fluorescent species, the unbound 16mer∗ had the highest effective negative charge and, thus, the highest electrophoretic mobility toward the positive (injection) end which corresponded to the longest migration time to the detection window (3.4 min).

What is meant by electrophoretic mobility?

Electrophoretic mobility is the solute’s response to the applied electrical field in which cations move toward the negatively charged cathode, anions move toward the positively charged anode, and neutral species remain stationary.

How do you control electroosmotic flow?

In aqueous capillary electrophoresis the electroosmotic flow (EOF) can be strongly suppressed or eliminated by coating the capillary surface silanols either by buffer additive adsorption or chemical modification.

What is Electroosmotic force?

Electroosmosis is a fundamental electrokinetic effect involving movement of the bulk solution against a charged solid surface under the influence of an electric field.

Which method is best for the separation of CE?

Capillary electrophoresis
Capillary electrophoresis is used most predominately because it gives faster results and provides high resolution separation. It is a useful technique because there is a large range of detection methods available.

How can electroosmotic flow be reduced?

Electroosmotic flow can be reduced by coating the capillary with a material that suppresses ionization of the silanol groups, such as polyacrylamide or methylcellulose.

Which of the following is NOT affect electrophoretic mobility?

8. Which of the following factors does not influence electrophoretic mobility? Explanation: The stereochemistry of molecule won’t have any effect on electrophoretic mobility since it is dependent on velocity and intensity and not allighnment.

What affects electrophoretic mobility?

(3) pH and other Chemical Characteristics- The electrophoretic mobility is greatly affected by the pH of a buffer, particularly when the sample is either a weak acid or a weak base, because the pH establishes its degree of ionization.

What is the measure of electrophoretic mobility μ Meas?

The measured electrophoretic mobility, μ meas, is a combination of the intrinsic electrophoretic mobility, μ ep, and the electroosmotic flow, μ eof. (8)μmeas=μep+μeof.

How is electroosmotic flow through microchannels modeled?

Electroosmotic flow through microchannels can be modeled after the Navier-Stokes equation with the driving force deriving from the electric field and the pressure differential. Thus it is governed by the continuity equation

Which is the permittivity of an electro-osmotic flow?

E = εζ η in terms of the permittivity ε and viscosity η of the fluid. EE, driven by slip at the surface. Typical flow speeds of 100 µm/sec (1 mm/min) are produced by fields of 100 Volt/cm. Electro-osmotic flows are very useful in modern microfluidic devices, since the flow speed is independent of channel radius.

Which is the correct definition of electroosmotic flow?

Electroosmotic flow (or electro-osmotic flow, often abbreviated EOF; synonymous with electroosmosis or electroendosmosis) is the motion of liquid induced by an applied potential across a porous material, capillary tube, membrane, microchannel, or any other fluid conduit.