Physical
Zeta potential
Convert electrophoretic mobility to zeta potential (Henry / Smoluchowski / Huckel).
ζ = 3 η μ / (2 ε_r ε₀ f)
Electrophoretic mobility in (µm/s)/(V/cm).
Default: water at 25 °C (0.89 mPa·s).
Default: water at 25 °C (78.5).
Protocol result
⚗ Aliquot
Zeta potential · ζ = 3 η μ / (2 ε_r ε₀ f) · the lab bench, calculated
Zeta✓ ζ = 3 η μ / (2 ε_r ε₀ f)
ζ = 12.8 mV
1
Stability rule of thumb: |ζ| > ~30 mV suggests good colloidal stability; near 0 mV suggests aggregation.
ℹ
Medium taken as viscosity 0.89 mPa·s and relative permittivity 78.5 (water at 25 °C unless you changed them).
ℹ
Smoluchowski limit (f = 1.5): valid for large κa (aqueous, larger particles, moderate-to-high salt).
ζ
12.8 mV
f(κa)
1.5