Hydrodynamic diameter (Z-average)
Intensity-weighted mean size of the particles as they move in liquid.
Useful forNanoparticles, colloids, liposomesSurface, Particle & Porosity
Particle Size Analysis Nano
Dynamic light scattering (DLS) for nanoparticles
Dynamic light scattering sizes nanoparticles, colloids and emulsions in liquid from the flicker of scattered laser light. It gives the hydrodynamic diameter and a polydispersity index within minutes.
1 test optionDynamic light scattering (DLS)Size range ~1 nm to a few µmTypical turnaround 3–5 working days
Particle Size Analysis Nano measurement principleIllustrative
01 / Overview
What is Particle Size Analysis Nano?
A laser lights particles in a cuvette as they drift by Brownian motion. Small particles move faster, so the light they scatter fluctuates faster. A detector and correlator measure how quickly the signal changes, and the Stokes–Einstein equation turns that diffusion rate into a hydrodynamic diameter.
DLS measures particles in their own liquid, including the solvation layer, so sizes often read larger than in electron microscopy. It suits fairly uniform samples from about 1 nm to a few micrometres; broader or coarser powders suit laser diffraction better.
02 / How it works
How it works
- 01
Sample is loaded
The dispersion is diluted if needed and pipetted into a clean cuvette, free of bubbles.
- 02
Laser lights the particles
A laser passes through the cuvette while the particles drift by Brownian motion.
- 03
Scattered light flickers
A detector records how the scattered intensity fluctuates; small particles make it flicker faster.
- 04
Size is calculated
The correlator gives the decay rate; the Stokes–Einstein equation turns it into size and PDI.
03 / What it measures
What it measures
Polydispersity index (PDI)
How broad the size distribution is, on a scale from near 0 to 1.
Useful forFormulation quality and batch checksSize distribution
Intensity-, volume- and number-weighted distributions.
Useful forSpotting aggregates or mixed populationsAggregation and stability
Repeat measurements track size changes over time or with temperature.
Useful forShelf-life and formulation studies04 / Test options
Choose the Particle Size Analysis Nano options you need
1 option · none added yet
05 / Sample requirements
Sample requirements
- Accepted forms
- Stable dispersions, colloids or emulsions; nanopowders with a named dispersant
- Quantity
- Typically 2–5 mL of dispersion, or 10–20 mg of powder
- Concentration
- Dilute, clear to slightly turbid; state the concentration
- Dispersant
- Name the liquid, its viscosity if unusual, and any additives
- Stable, well-dispersed sample without visible sediment
- Name the dispersant and the concentration
- Mention any sonication, filtering or dilution already done
- Sealed, leak-proof, labelled vials
- No fast-settling samples or particles larger than a few µm
- No opaque or highly concentrated dispersions without discussing first
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
- Z-average hydrodynamic diameter and PDI
- Intensity, volume and number size distributions
- Correlation function and fit quality
- Measurement conditions: dispersant, temperature, angle
- 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 Particle Size Analysis Nano isn't the right fit
Coarse or broad samples above a few µm
Particle shape or individual particle images
Surface charge and dispersion stability
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