Nanoparticle Size and Zeta Potential Analysis using DLS (Dynamic Light Scattering) is a widely adopted non-destructive technique for characterizing colloidal dispersions and nanoscale particles in suspension. It enables precise measurement of particle size distribution, aggregation behavior, and surface charge (zeta potential), which are critical for understanding colloidal stability, formulation behavior, and interfacial interactions.
This technique is essential in the development of nanomaterials, drug delivery systems, coatings, inks, and emulsions, where particle behavior in solution determines functionality and performance.
Principle
Principle
DLS and electrophoretic light scattering are used to obtain particle size and zeta potential:
Particle Size – DLS Principle:
Nanoparticles in suspension undergo Brownian motion.
A laser beam illuminates the particles, and scattered light is detected over time.
The fluctuation of scattering intensity is analyzed using autocorrelation functions to calculate the hydrodynamic diameter (via the Stokes–Einstein equation).
Zeta Potential – ELS Principle:
An electric field is applied to the particle suspension.
Particles migrate depending on their surface charge.
The electrophoretic mobility is measured via laser Doppler velocimetry.
Zeta potential is calculated, indicating electrostatic repulsion and colloidal stability.
Principle
Typically 1–1000 nm for spherical particles in DLS mode; highly polydisperse samples may require additional interpretation.
Minimum 0.5 mL for size; 1 mL for zeta potential with capillary cells.
Yes, depending on refractive index and viscosity; please provide solvent details.
It indicates strong electrostatic repulsion and good colloidal stability. Typically, ±30 mV or more is considered stable.
Test Procedure
DLS-based analysis applies to a broad spectrum of nano- and micro-scale suspensions, including:
Material types: polymers, metal/oxide nanoparticles, liposomes, emulsions, protein complexes, quantum dots, nanofluids
Caption: Size distribution of polymer nanoparticles using DLS
Caption: Zeta potential of gold nanoparticles in citrate buffer
Test Procedure
To obtain accurate and repeatable results, please follow these sample guidelines:
Volume:
Size only: ≥ 0.5 mL (disposable cuvette)
Size + Zeta: ≥ 1.0 mL (for capillary cells)
Concentration: Typical range 0.1–10 mg/mL depending on material
Condition: Homogeneous, stable dispersion; avoid bubbles and large aggregates
Solvent compatibility: Aqueous or organic solvents — please specify system type
Contact us if you're unsure about compatibility, solvents, or dispersion protocols.
Test Procedure
Our DLS and zeta potential testing includes the following steps:
Sample preparation: Filter (if required), dilute, or sonicate samples based on concentration and dispersion state.
Instrument setup: Select appropriate scattering angle and cell type (cuvette, capillary, disposable).
Measurement: Perform size and zeta measurements under controlled temperature and voltage.
Data analysis: Evaluate intensity, number, and volume-based size distributions; calculate mean size and zeta potential values.
Report generation: Provide data graphs, distribution curves, and summary analysis in a comprehensive PDF report.
Nanoparticle Size and Zeta Potential Analysis using DLS (Dynamic Light Scattering) is a widely adopted non-destructive technique for characterizing colloidal dispersions and nanoscale particles in suspension. It enables precise measurement of particle size distribution, aggregation behavior, and surface charge (zeta potential), which are critical for understanding colloidal stability, formulation behavior, and interfacial interactions.
This technique is essential in the development of nanomaterials, drug delivery systems, coatings, inks, and emulsions, where particle behavior in solution determines functionality and performance.
