Reversed micelles as matrix microreactors for chemical processing of macromolecules

Abstract

Being solubilized in the systems of the surfactant reversed micelles (RM), the macromolecules incorporate into the inner cavity of RM, whose size can be changed by varying the surfactant hydration degree Wo, i.e. [H2O]/[Surfactant] molar ratio. The conjugates of macromolecules (protein‐protein, protein‐linear polyelectrolyte) are synthesized in RM of AOT (Aerosol OT, sodium bis[2‐ethylhexyl]sulfosuccinate) in octane. The yield critically depends on the hydration degree: the reaction does not proceed at low Wo, but at Wo exceeding threshold value (which differs for various macromolecules) the yield increases sharply and reaches 100%. Using the ultracentrifugation it was demonstrated that at Wo lower than threshold the polyelectrolyte represents a compact globule compressed by the micellar matrix in the RM inner cavity. Under these conditions there is no space for the protein in the RM, containing polyelectrolyte, and therefore reaction does not proceed. At Wo higher than threshold RM become large enough to entrap the conjugated macromolecules simultaneously. The possibility of regulation of the conjugate composition by variation of Wo (size of micellar matrix) was demonstrated. The RM are applied as universal matrix microreactors, for modification of macromolecules with water insoluble reagents and for regulation of supramacromolecular composition of oligomeric enzymes.