Back-extraction mechanism of lysozyme from reverse micelles in sodium bis 2-ethylhexyl sulfosuccinate and long chain alkyl amine mixed systems

Extraction and back-extraction of lysozyme are investigated using a mixed micellar system of sodium bis(2-ethylhexyl) sulfosuccinate and long chain alkyl amines. Either di-n-octylamine or di-2-ethylhexylamine is used as the amine added. In these systems, reverse micelles is not formed at acidic pH range. Lysozyme extracted at pH which is slightly lower than the isoelectric point of lysozyme is successfully back-extracted by destruction of the micelles at acidic pH range. By increasing the amine concentration, the pH values, at which the back-extraction of lysozyme began, are raised, and the activity of the back-extracted lysozyme decreases. Linear relationship between the concentration of the amine added in the system and that of lysozyme back-extracted exists .