Reversed Micellar Extraction

Reverse Micellar Extraction for Downstream Processing of Proteins/Enzymes... 

Technology Development Aspects of Reverse Micellar Extraction. 157... 

AOT sodium bis(2-ethyl-l-hexyl) sulfosuccinate, aerosol OT ARMES affinity based reverse micellar extraction and separation... 

Reverse micellar extraction (RME) is another attractive LLE method for DSP of biological products, as many biochemicals including amino acids, proteins, enzymes, and nucleic acids can be solubilized within and recovered from such solutions without loss of native function/activity. In addition, these systems offer low interfacial tension, ease of scale-up, and continuous operation. RME offers a number of unique, desirable features in comparison with ATPE, which has been extensively studied ... 

In order to describe and optimize the reverse micellar extraction process, Dekker et al. [ 170] have proposed a mathematical model, which satisfactorily describes the time dependency of the concentration of active enzyme in all the phases, based on the flow, mass transfer, and first-order inactivation kinetics. For each phase, a differential equation is derived. For forward extraction ... 

A simplified equilibrium extraction model (Fig. 6) was presented by Dordick and colleagues [188] to explain the resolution behavior of glycoproteins in affinity based reverse micellar extraction and separation (ARMES). Their system for the study includes soybean peroxidase (SBP, MW 37 KDa, pi 4.1) and aj-acid glycoprotein (AGP, MW 43 KDa, pi 3.7) as glycoprotein solutes, concanavalin A (ConA) as the affinity ligand in AOT/isooctane RMs. The separation factor (a) for the separation of SBP from AGP can be given by... 

Affinity Based Reverse Micellar Extraction and Separation (ARMES)... 

An alternative to the injection method for importing enzymes into a microemulsion is the phase transfer method. In this method, a layer of an aqueous enzyme solution is located under a mixture of surfactant and oil. Upon gentle shaking, the enzyme is transferred into the reverse micelles of the hydrocarbon phase. Finally, the excess of water is removed and the hydrophobic substrates can be added. The main advantage of this method is that it ensures thermodynamically stable micro emulsions with maximum water concentrations. However, the method is very time consuming. The method is often applied in order to purify, concentrate or renaturate enzymes in the reverse micellar extraction process [54-58]. 

The physico-chemical interactions that can be exploited in the selection and optimisation of these processes are discussed below. We will reserve for future communications a detailed discussion of the technological aspects and potential problems in the implementation of reversed micellar extraction of bioproducts in large-scale continuous operations, these topics being beyond the scope of this overview. 

Dekker [3] and Hatton [4] developed this process systematically for practical uses. They also demonstrated the factors affecting the protein separation based on the reverse micellar extraction. A recent review summarized the factors clarified so far [5]. 

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