Estimate micelle size using molecular weight or concentration. Validate inputs, track runs, and compare scenarios. Download CSV and PDF summaries for your notebook easily.
| Scenario | Method | Key inputs | Nagg |
|---|---|---|---|
| Micelle by Mw | Molecular-weight ratio | Mw(agg)=57,600 g/mol; Mw(mono)=288 g/mol | 200 |
| Cluster counts | Count ratio | Total molecules=2.40×1018; Aggregates=2.00×1016 | 120 |
| Above CMC | Concentration-to-count | Ctotal=0.050; CMC=0.008; V=0.250 L; Micelles=1.50×1020 | 42.2 |
| Time | Method | Nagg | Inputs |
|---|---|---|---|
| No history yet. Submit a calculation to start tracking runs. | |||
Aggregation number (Nagg) links microscopic structure to macroscopic behavior. In micellar systems, it influences solubilization capacity, viscosity trends, and interfacial activity. A higher Nagg typically indicates larger assemblies, which can shift light scattering intensity and alter diffusion. Tracking Nagg across temperature, ionic strength, and co-solvent fraction helps explain phase boundaries and stability windows in formulation work.
The calculator supports three pathways that map to common lab data streams. The molecular-weight ratio approach fits datasets from static light scattering, SEC-MALS, or calibrated mass measurements. The count ratio method is useful when microscopy, particle counting, or simulation outputs provide aggregate counts directly. The concentration-to-count approach matches studies where CMC is known and aggregate number density can be estimated from scattering models.
Aggregation estimates are sensitive to unit consistency and baseline assumptions. Concentrations must be in mol/L and volume in liters for the Avogadro conversion. For the micelle method, Ctotal must exceed CMC; otherwise, micellized material is effectively zero. Using scientific notation for large counts prevents rounding errors when values exceed 1012. The step summary helps confirm each intermediate quantity before reporting.
Nagg is not a universal constant; it shifts with surfactant type, counterions, additives, and concentration. When comparing runs, keep temperature and ionic strength fixed, then vary one factor at a time. If Nagg rises while CMC falls, stronger hydrophobic association is a plausible driver. If Nagg falls with added salt, electrostatic screening may be changing curvature or promoting smaller aggregates depending on headgroup chemistry.
The history table stores recent calculations so you can compare scenarios in one session. Exporting CSV supports quick import into spreadsheets for plotting Nagg versus concentration or temperature. The PDF export captures the same table for lab notebooks, QA packets, or client deliverables. Together, these outputs standardize reporting and make it easier to reproduce calculations during audits and peer review. Add notes on sample ID, buffer, and instrument settings to keep your aggregation datasets comparable. Consistent metadata improves traceability and reduces recalculation when methods change later unexpectedly.
It is the average number of monomers or surfactant molecules contained in one aggregate, such as a micelle, vesicle, or cluster, under specified conditions.
Start with the molecular-weight ratio if you have reliable Mw values. Use count ratio when you have particle counts. Use the concentration method when CMC is known and you can estimate micelle number density.
Below CMC, most surfactant remains as monomers, so the micellized fraction is negligible. The concentration method assumes only the excess over CMC contributes to micelles.
Yes. Inputs accept formats like 1.5e20 for large counts. This helps keep precision when working with Avogadro-scale quantities or model-derived number densities.
Not necessarily. Real systems show distributions of aggregate sizes, so Nagg is often a non-integer average. Rounding for reporting is acceptable, but keep raw values for comparisons.
Report temperature, ionic strength, solvent composition, concentration, and measurement technique. These factors strongly influence aggregation and help others reproduce or compare your results.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.