Nanoparticles vs. microspheres
Use explicit units and size values.
Sub-micron to one-micron pathway
Larger spherical silica in a prepared commercial family.
Applied Physics currently presents a 250–1000 nm silica microsphere family at a public 10 wt% configuration. Exact size points, carrier, tolerance, package volume and certificate scope must be confirmed.
250 nm0.25 µm
500 nm0.50 µm
750 nm0.75 µm
1000 nm1.00 µm
Why the larger range matters
Size changes settling, scattering, count and preparation behavior.
| Effect | As diameter increases | Technical consequence |
|---|---|---|
| Mass per ideal sphere | Increases with the cube of diameter | Particle count per unit mass falls rapidly |
| Settling tendency | Generally increases with size and density under comparable conditions | Stock homogeneity and time-to-use matter more |
| Optical response | Often increases, but the regime and instrument remain decisive | Do not extrapolate linearly across sizes |
| Surface area per unit mass | Generally decreases for larger ideal spheres | Surface-driven formulation behavior changes |
| Wafer response | Can become easier to detect, but material and tool still control | Use multiple controlled size points for sensitivity work |
Selection and handling
Build a size-specific procedure.
- Define nominal size and accepted measurement method
- Review distribution width and evidence of larger contaminants
- Confirm medium and concentration
- Set validated re-mixing and time-to-use instructions
- Control dilution and container adsorption
- Verify optical, wafer or process response in the receiving method
- Document storage and expiration
Count estimation
Diameter strongly changes idealized particles per milligram.
Because ideal-sphere volume scales with diameter cubed, doubling diameter produces eight times the volume and mass at constant density. Use the particle-count estimator for planning, then replace idealized assumptions with product-specific density, distribution and concentration evidence.
Questions engineers ask
Frequently asked questions
Are 250–1000 nm particles nanoparticles or microspheres?
Commercial naming varies. Use explicit nominal diameter and method. This site calls the family microspheres to distinguish it from the smaller 20–200 nm family.
Is 1000 nm equal to 1 µm?
Yes. 1000 nanometers equals 1 micrometer.
Sources and verification
Technical basis
- Applied Physics 250–1000 nm silica microspheres — Current public family reference.
- NIST measurement protocols — Supports method and uncertainty review.
- NIST TEM sizing — Image-based size-measurement reference.
Commercial specifications should be confirmed against the current Applied Physics quotation, certificate, lot documentation and product page before purchase or protocol use.
Continue the research
Related technical guidance
Particle-count estimator
Model count from size, density and mass.
Optical scattering
Understand size-dependent response.
Applied Physics technical pathway
Need a particle specification reviewed?
Send the target size, medium, concentration, application, certificate requirements and shipping destination. Applied Physics can evaluate the appropriate silica family or custom pathway.