Choose water when
- The instrument or process is water-based
- Low flammability is important
- The particle is stable in the required aqueous chemistry
- Dilution water quality can be controlled
The medium is part of the product
Water and ethanol change more than drying time.
The dispersant controls viscosity, dielectric environment, wetting, evaporation, safety controls, compatibility, electrokinetic behavior and the practical dilution pathway.
| Factor | Aqueous dispersion | Ethanol dispersion |
|---|---|---|
| Process compatibility | Useful for water-compatible systems and many metrology workflows | Useful where faster evaporation or solvent compatibility is required |
| Flammability | Generally avoids ethanol flammability hazards | Requires flammable-liquid controls and compatible storage |
| Surface wetting | Depends on native or modified silica and water chemistry | Can improve wetting in some organic systems but is not universally stabilizing |
| Dilution | Diluent purity, pH, conductivity and ions matter | Solvent grade, water content and formulation compatibility matter |
| Evaporation | Slower; evaporation can still concentrate salts and solids | Faster; can alter concentration quickly and create vapor-control needs |
| Equipment compatibility | Check corrosion, optics, seals and microbiological controls | Check seals, plastics, ignition sources and ventilation |
Decision sequence
Select the medium from the downstream process.
Choose ethanol when
- The process requires an alcohol carrier
- Evaporation behavior is useful
- Materials are solvent-compatible
- Flammable-liquid controls are established
Escalate when
- Solvent exchange is planned
- The target matrix contains salts or polymers
- The surface is functionalized
- Particle deposition uniformity is critical
Incoming inspection
Document the supplied medium as received.
- Exact carrier and any stated stabilizer
- Nominal concentration and units
- pH or water content where relevant
- Lot, expiration and storage requirements
- Visual appearance and evidence of sedimentation
- Mixing instructions before withdrawal
- SDS and transportation classification
Applied Physics presents both aqueous and ethanol pathways within parts of its silica portfolio. Availability and exact formulation should be confirmed by size and product configuration.
Questions engineers ask
Frequently asked questions
Is ethanol always better for hydrophobic silica?
No. Surface treatment, stabilizer, solids loading and downstream compatibility determine the appropriate medium.
Can I directly exchange an aqueous dispersion into ethanol?
Only with a validated process. Rapid solvent exchange can destabilize particles, alter surface chemistry or create irreversible association.
Sources and verification
Technical basis
- Applied Physics 20–200 nm silica dispersions — Current commercial family showing aqueous and ethanol options.
- Applied Physics amine-functionalized silica — Example of a functionalized ethanol-dispersion pathway.
- NIOSH nanomaterial handling — Occupational-control framework for engineered nanomaterials.
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
Dry powder vs. suspension
Compare prepared and carrier-free formats.
Zeta potential
Evaluate condition-specific colloidal behavior.
Dilution calculator
Calculate volumes after the medium is selected.
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.