Written and maintained by CASRAI Editorial Board
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Reader task: a researcher or core-facility user who has seen “Zetasizer”, “NanoSight” or “Mastersizer” on a methods section or instrument list and needs to know what each system reports and which size window it covers.
Short answer
The Zetasizer is Malvern Panalytical’s family of light-scattering instruments for characterising particles and molecules in suspension or solution. The current Zetasizer Advance range measures size by dynamic light scattering (DLS), zeta potential by electrophoretic light scattering, and molecular weight by static light scattering. NanoSight (nanoparticle tracking analysis) and Mastersizer (laser diffraction) are separate Malvern Panalytical product lines that cover different size windows and report different quantities.
Definition and scope
“Zetasizer” is a product name, not a measurement technique. The manufacturer’s support pages list several Zetasizer ranges (Advance, Core, AT, WT, Nano, uV and Helix); this page covers the Advance range, whose entry-level, mid-range and top models are called Lab, Pro and Ultra. The measurement concepts behind it, such as zeta potential, are explained on their own pages and are not repeated here.
This page is general technical information about what the instruments are specified to do. It is not an operating procedure, and it does not tell you which instrument or model a particular study should use.
How the Zetasizer Advance range works in practice
According to Malvern Panalytical’s product-range page for the Zetasizer Advance range, the platform combines these techniques:
- Dynamic light scattering (DLS): non-invasive backscatter (NIBS) DLS and classic DLS at 90 and 13 degrees, reporting particle size. For how to read the output, see Z-average, PDI and how to read a DLS report.
- Multi-angle DLS (MADLS): listed by the manufacturer for the Ultra model only.
- Zeta potential: measured by phase analysis light scattering using the manufacturer’s Mixed-Mode Measurement (M3-PALS) approach. The manufacturer cites USP <432>, “Determination of Zeta Potential by Electrophoretic Light Scattering”.
- Static light scattering: with a Debye plot, for molecular weight.
Stated specifications on the same page include a size range of 0.3 nm to 15 µm, a zeta-potential particle-size range of 3.8 nm to 100 µm, and sample concentrations for zeta measurements from 1 mg/mL to 70% w/v, depending on the sample. The page states that the 15 µm upper size limit applies to 90-degree-capable systems using a low-volume capillary cell and extended-range analysis; otherwise the upper limit is 10 µm.
Lab, Pro and Ultra models
| Model | DLS angles | Size range (as stated) | Minimum sample volume (as stated) |
|---|---|---|---|
| Zetasizer Lab | 90 and 13 degrees | 0.3 nm to 15 µm | 3 µL |
| Zetasizer Pro | 173 and 13 degrees | 0.3 nm to 10 µm | 12 µL |
| Zetasizer Ultra | 173, 13 and 90 degrees | 0.3 nm to 15 µm | 3 µL |
Source: Malvern Panalytical, Zetasizer Advance range page, read 2026-11-08. Only the rows that are stated unambiguously on the manufacturer’s page are reproduced.
Related instruments: NanoSight and Mastersizer
Searchers often meet the Zetasizer next to two other Malvern Panalytical names. They are different product lines, each with its own stated technology and size window.
NanoSight
The NanoSight range uses nanoparticle tracking analysis. The manufacturer states a size range of 10 nm to 1000 nm and a concentration range of 106 to 109 particles/mL, both dependent on the sample and instrument configuration. Its light-scatter mode measures individual nanoparticles, and an optional fluorescence mode detects labelled subpopulations. The support page lists NS300, LM10 and Pro.
Mastersizer
The Mastersizer 3000+ range “uses laser diffraction to measure the particle size, and size distribution”. Stated ranges are 0.01 to 3500 µm (Ultra), 0.1 to 2500 µm (Pro) and 0.1 to 1000 µm (Lab).
Cross-walk of the three families
| Zetasizer Advance | NanoSight | Mastersizer 3000+ | |
|---|---|---|---|
| Technique stated by manufacturer | DLS, electrophoretic light scattering, static light scattering | Nanoparticle tracking analysis | Laser diffraction |
| Quantities named on the product page | Size, zeta potential, molecular weight | Size and particle concentration, with optional fluorescence detection | Particle size and size distribution |
| Stated size window | 0.3 nm to 15 µm | 10 nm to 1000 nm | 0.01 to 3500 µm (Ultra); 0.1 to 1000 µm (Lab) |
Source: Malvern Panalytical product-range pages, read 2026-11-08. Size windows are the manufacturer’s stated figures and depend on sample and configuration.
Editorial reading of those figures: the stated ranges overlap between roughly 10 nm and 1 µm for the Zetasizer and NanoSight, and between about 0.1 µm and 15 µm for the Zetasizer and the Mastersizer Lab and Pro models. Overlapping ranges mean more than one instrument can report on a sample, but the pages do not state that the results are interchangeable, and each reports different quantities.
Where it matters for labs
- Methods reporting: naming the model (Lab, Pro or Ultra), the angle used and the measured quantity gives readers what they need to judge a result, because the models differ in angles, upper size limit and minimum volume (table above).
- Matching the question to the output: size distribution of a powder or emulsion in the micrometre range points to the laser-diffraction family; particle counts in the 10 to 1000 nm range point to nanoparticle tracking; size, charge or molecular weight of colloids and macromolecules point to the Zetasizer. This is an editorial summary of the stated outputs, not manufacturer guidance.
- Related consumables and context: light-scattering work uses sample cells; see what a cuvette is. For a different size and structure method, see X-ray diffraction.
Common misunderstandings
- “Zetasizer” only measures zeta potential. The name suggests so, but the manufacturer lists size and molecular weight techniques on the same platform.
- All three instruments are interchangeable particle sizers. They use different techniques and report different quantities; a shared size range does not make their outputs equivalent.
- The upper size limit is always 15 µm. The manufacturer states 15 µm only for 90-degree-capable systems with a low-volume capillary cell and extended-range analysis; otherwise 10 µm.
FAQ
What is the difference between a Zetasizer and a NanoSight?
The Zetasizer Advance range is specified for DLS size, zeta potential and static-light-scattering molecular weight over 0.3 nm to 15 µm. NanoSight uses nanoparticle tracking analysis over 10 nm to 1000 nm and reports particle concentration alongside size, with optional fluorescence detection.
What is the difference between a Zetasizer and a Mastersizer?
The Mastersizer 3000+ uses laser diffraction for particle size and size distribution, with ranges reaching up to 3500 µm on the Ultra model. The Zetasizer is specified for smaller sizes (0.3 nm to 15 µm) and also covers zeta potential and molecular weight.
Which Zetasizer models exist in the Advance range?
Lab, Pro and Ultra. See the model table above for angles, upper size limit and minimum sample volume.
Sources
- Malvern Panalytical, Zetasizer Advance range (read 2026-11-08).
- Malvern Panalytical, Zetasizer range product support (read 2026-11-08).
- Malvern Panalytical, NanoSight range (read 2026-11-08).
- Malvern Panalytical, Mastersizer range (read 2026-11-08).
- Malvern Panalytical, Zeta potential measurement (read 2026-11-07).
