Zeta potential (mV)
Size and sign of the effective surface charge in the liquid.
Useful forNanoparticles, colloids, emulsionsSurface, Particle & Porosity
Zeta Potential Measurement
Surface charge of particles by electrophoretic light scattering
Zeta potential measures the effective surface charge of particles in a liquid from how fast they move in an electric field. It is used to judge dispersion stability and how surfaces respond to pH or additives.
1 test optionElectrophoretic light scatteringResult in millivolts (mV)Typical turnaround 3–5 working days
Zeta Potential Measurement measurement principleIllustrative
01 / Overview
What is Zeta Potential Measurement?
An electric field is applied across the dispersion in a folded capillary cell. Charged particles drift towards the opposite electrode, and a laser measures their speed from the Doppler shift of the scattered light. The Henry equation converts this electrophoretic mobility into zeta potential.
The result reflects the charge at the slipping plane around each particle, which governs how strongly particles repel one another. As a rough guide, values beyond about ±30 mV suggest good stability, while values near zero point to aggregation.
02 / How it works
How it works
- 01
Cell is filled
About 1 mL of the dispersion is injected into a folded capillary cell, without air bubbles.
- 02
Field is applied
A voltage across the electrodes makes charged particles drift towards the opposite electrode.
- 03
Laser tracks the motion
Light scattered by the moving particles is Doppler-shifted; the frequency shift gives their speed.
- 04
Zeta potential is calculated
Mobility is converted to zeta potential with the Henry equation and reported as a distribution.
03 / What it measures
What it measures
Electrophoretic mobility
How fast the particles move per unit of applied field.
Useful forComparing surface treatments and coatingsDispersion stability
A larger magnitude, typically beyond ±30 mV, means stronger repulsion.
Useful forInks, slurries, suspensions and formulationsZeta potential vs pH (on request)
Measurements across a pH range locate the isoelectric point.
Useful forOxide, pigment and protein surfaces04 / Test options
Choose the Zeta Potential Measurement options you need
1 option · none added yet
05 / Sample requirements
Sample requirements
- Accepted forms
- Aqueous or polar-solvent dispersions, colloids, emulsions; powders with a named medium
- Quantity
- Typically 2–5 mL of dispersion, or 10–20 mg of powder
- Concentration
- Dilute, at most slightly turbid; state the concentration
- Medium
- State pH and salt content; very high conductivity limits the measurement
- Well-dispersed, stable sample
- State the dispersant, pH and any salts or surfactants
- Say if a specific pH or dilution medium is needed
- Leak-proof, labelled vials
- No non-polar solvent dispersions without discussing first
- No coarse or fast-settling suspensions
Hazardous or air-sensitive samples: mention it in your request, and attach the MSDS if you have one.
06 / Results & turnaround
Results & turnaround
What you receive
- Mean zeta potential (mV) with standard deviation
- Zeta potential distribution plot
- Electrophoretic mobility and sample conductivity
- Measurement conditions: medium, pH, temperature
- Report PDF
Turnaround & pricing
Typically 3–5 working days after samples reach the lab.
Price confirmed in your quotation, depending on user type, options and number of samples.
07 / Limitations
When Zeta Potential Measurement isn't the right fit
Particle size or size distribution
Surface chemistry of dry solids
Wettability of flat surfaces
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