Particle Characterization

Frequently Asked Questions

What does zeta potential measure?

Zeta potential measures the electrical charge at the surface of particles in suspension, which governs how strongly particles repel or attract each other. It is the standard predictor of colloidal (physical) stability: suspensions with a zeta potential far from zero (typically beyond ±30 mV) tend to resist aggregation, while values near zero predict flocculation or sedimentation.

What does DLS (dynamic light scattering) measure?

DLS determines particle size distribution in suspension by analyzing how particles scatter laser light as they move under Brownian motion. It reports the mean hydrodynamic diameter and the polydispersity index (PDI), which indicates how uniform or broad the size distribution is.

How are zeta potential and DLS used together?

Zeta potential explains why a suspension is stable or unstable; DLS shows the resulting particle size and its distribution. Run together, they connect formulation variables (pH, ionic strength, surfactant, stabilizer) to both the driving force of stability and its physical outcome — the standard pairing for nanoemulsion, liposome and suspension development.

What sample types can be analyzed by zeta potential and DLS?

Both techniques run on liquid suspensions and dispersions — nanoparticles, emulsions, liposomes and colloidal formulations across pharmaceutical, cosmetic and materials applications. Sample concentration and dilution requirements are confirmed for each project.

Which lab performs zeta potential and DLS analysis in Brazil?

Percevia is a Brazilian analytical laboratory based in São Paulo, offering zeta potential and dynamic light scattering (DLS) as outsourced analytical services for pharmaceutical, cosmetics and materials companies developing colloidal formulations.