20–200 nm dry silica
Evaluate when carrier-free sub-200 nm material is required and a validated dispersion workflow exists.
Format is a process decision
Prepared suspension reduces one burden; dry powder transfers it to the user.
A dispersion can provide a controlled starting medium and concentration. A dry powder provides carrier flexibility and shipping efficiency but requires validated wetting, deagglomeration, contamination control and occupational-safety procedures.
| Decision factor | Prepared dispersion | Dry powder |
|---|---|---|
| Starting state | Particles supplied in a defined liquid medium | Carrier-free particulate solid |
| Main advantage | Reduced initial wetting and dispersion burden | Maximum formulation and carrier flexibility |
| Main risk | Stability, shelf life, evaporation and medium compatibility | Dust exposure, difficult redispersion and batch-to-batch process variability |
| Concentration adjustment | Dilute from a documented stock concentration | Weigh and disperse, adding mass and volume uncertainty |
| Contamination control | Container opening, pipetting and diluent quality | Weighing environment, tools, airborne contamination and vessel cleanliness |
| Characterization after preparation | Verify condition after dilution or solvent change | Verify effective size after the full dispersion process |
Dry-powder workflow
Do not write “add powder and mix.”
- Define the target carrier, concentration and final application.
- Review the SDS, exposure controls and required containment.
- Select a compatible clean vessel and documented water or solvent grade.
- Define addition order, wetting aid if permitted, mixing energy and temperature limits.
- Validate the procedure at small scale.
- Measure the resulting particle population and application response.
- Set hold time, storage and re-mixing limits.
Applied Physics pathways
Compare current dry and dispersed families.
100 nm–2.5 µm dry silica
Broader dry-size pathway for formulation, research and application-specific evaluation.
Prepared dispersions
Evaluate when a controlled aqueous or ethanol stock better fits the method.
Questions engineers ask
Frequently asked questions
Is dry powder more concentrated than a suspension?
It is carrier-free, but useful solids content after redispersion depends on the formulation and process. “More concentrated” does not mean easier to use.
Can dry silica powder be redispersed to the original primary-particle size?
Not automatically. Drying history and interparticle contacts can produce structures that do not fully redisperse.
Sources and verification
Technical basis
- NIOSH nanomaterial handling guidance — Supports exposure-control planning for dry engineered nanomaterials.
- Applied Physics dry silica powder — Current sub-200 nm powder pathway.
- Applied Physics broader dry silica — Current broader dry-size family.
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
Storage and safety
Control dry-powder and dispersion hazards.
Particle-count estimator
Estimate idealized particle counts with assumptions exposed.
Aggregation and agglomeration
Evaluate redispersion and association.
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.