mikellikonentraatio

Mikellikonentraatio is the concentration of micelles in a solution that contains surfactant molecules. It becomes relevant once the total surfactant concentration exceeds the critical micelle concentration (CMC), the threshold at which individual surfactant molecules begin to assemble into micellar aggregates. In typical solutions, the monomer concentration remains close to the CMC, while the excess surfactant forms micelles.

A practical way to express mikellikonentraatio is approximately [Micelles] ≈ (C_total − CMC)/N_agg, where C_total is the total surfactant concentration and N_agg is the aggregation number, i.e., the average number of surfactant molecules per micelle. N_agg varies with the surfactant type and experimental conditions, and can range from a few tens to a few hundred. This relationship is an approximation that assumes equilibrium between monomers and micelles and a relatively narrow size distribution.

Several factors influence mikellikonentraatio, including temperature, ionic strength, pH, and the presence of additives or co-surfactants. Ionic surfactants are particularly sensitive to electrostatic interactions, which can affect both CMC and N_agg. The concept is widely used in formulation science, detergency, cosmetics, and drug delivery, where understanding micelle abundance helps predict solubilization capacity, release kinetics, and transport properties.

Measurement and estimation of mikellikonentraatio employ methods such as dynamic and static light scattering, fluorescence probes, SAXS or cryo-electron microscopy, and conductometry for assessing CMC. Direct counting of micelles in solution is challenging due to their dynamic, heterogeneous nature.