Recovery of proteins and amino acids from reverse micelles by dehydration with molecular sieves

Abstract

A new method is presented to precipitate proteins and amino acids from reverse micelles by dehydrating the micelles with molecular sieves. Nearly complete precipitation is demonstrated for alpha-chymotrypsin, cytochromec, and trytophan from 2-ethylhexyl sodium sulfosuccinate (AOT)/isooctane/water reverse micelle solutions. The products precipitate as a solid powder, which is relatively free of surfactant. The method does not require any manipulation of pH, ionic strength, temperature, pressure, or solvent composition, and is applicable over a broad range of these properties. This general approach is compared with other techniques. This general approach is compared with other techniques for the recovery of biomolecules from reverse micelles. (c) 1994 John Wiley & Sons, Inc.

Mechanism of protein extraction from the solid state by water-in-oil microemulsions

“…The presence of salt in the solid phase also led to an increased desorption of water without changing the extent of AOT desorption. Moreover, the addition of solid salt dehydrates w/o-MEs without desorption of surfactant, in similar fashion to that reported for molecular sieve treatment (Gupta et al, 1994). Dehydration of solid proteins or the presence of salt in the solid phase led to an increase in the solubilization of LYS and BSA but decreased the uptake of CHY (data not shown).…”

Role of alcohols in the formation of inverse microemulsions and back extraction of proteins/enzymes in a reverse micellar system

“…They include: (a) use of silica particles for the sorption of the proteins as well as surfactants and water directly from protein-filled reverse micelles [33]; (b) addition of dewatering agents such as isopropyl alcohol [5] and dehydration of reverse micelles with molecular sieves to recover protein [34]; (c) formation of clathrate hydrates via pressurization [35]; (d) use of NaDEHP/isooctane/brine reverse micelles which can easily be destabilized by adding divalent cations (such as Ca 2+ ) and subsequent release of protein into the aqueous media [36]; (e) addition of sucrose to enhance protein recovery by reducing the protein-surfactant interactions [37]; (f) back extraction with the aid of a counter-ionic surfactant [38][39][40] and through gas hydrates formation [41].…”

Colloidal gas aphrons (CGA): Dispersion and structural features

“…tail hydrophobic part is around 8.3 A and the diameter of Ž . the polar head is around 3.5 A Gupta et al, 1994 , so the total length of an AOT molecule is 12 A or 1.2 nm, and therefore around 80 molecules of surfactant could fit in this Ž interface this does not allow for an inner water phase of . A transmission electron microscope TEM was used; the sample being prepared using the freeze fracture method.…”