Solubilization of enzymes in water-in-oil microemulsions and their rapid and efficient release through use of a pH-degradable surfactant

Abstract

alpha-Chymotrypsin and lysozyme were solubilized in a water/O-[(2-tridecyl, 2-ethyl-1,3-dioxolan-4-yl)methoxy]-O'-methoxy poly(ethylene glycol) (CK-2,13 surfactant)/isooctane water-in-oil microemulsion solution at 1.5-2 and 10 g l(-1) for 0.15 and 1.2 M: CK-2,13, respectively. Upon contact with an equal volume of 0.1 M: NaH(2)PO(4)/Na(2)HPO(4) buffer, pH 5, a three-phase system (Winsor-III system) was formed, consisting of a surfactant-rich middle phase and aqueous and isooctane-rich "excess" phases. Both enzymes were rapidly released into the aqueous excess phase, with 70% recovery of each in 30 and 60 min for microemulsion solutions containing 0.15 and 1.2 M: surfactant, respectively. The recovered enzymes retained >90% of their original specific activity.

Characterization of Microemulsion Systems Formed by a Mixed 1,3‐Dioxolane Ethoxylate/Octyl Glucoside Surfactant System

“…There have only been a few reports of use of triggerable surfactants for microemulsion formation to date [3,4]. An acid-cleavable alkyl ethoxylate referred to as ''CK-2,13'', 4-CH 3 O(CH 2 CH 2 O) 7.2 -CH 2 , 2-(CH 2 ) 12 CH 3 , 2-(CH 2 )CH 3 , 1,3-dioxolane forms microemulsion systems with behavior similar to those formed by linear alkyl ethoxylates (C i E j s), except that CK-2,13 undergoes apparent zeroth-order hydrolysis when in contact with buffer solution of pH \ 7, and is a less efficient amphiphile than C i E j s, i.e., has a high critical microemulsion concentration, presumably because of the stiffness in the molecule imparted by the 1,3-dioxolane ring and the broad molecular weight distribution of its ethoxylate groups [5][6][7]. To improve the performance of CK-2,13, its combination with a second surfactant species has been pursued.…”

Model-based experimental analysis of enzyme kinetics in aqueous–organic biphasic systems

“…Emulsions serve not only as reaction systems for enzymatic conversions involving hydrophobic reactants, but also as vehicle for drug delivery (Klyachko and Levashov, 2003;Lawrence and Rees, 2000;Rairkar et al, 2007). However, until today no possibility exists for studying emulsions in small scale using quasi-continuous measurement techniques.…”

Mobilization and Biodegradation of 2-Methylnaphthalene by Amphiphilic Polyurethane Nano-Particle

“…The mechanism of solubilizing the non-polar material by APU is similar to that of the micelle. This increased solubilization can be used in the enhanced soil washing by surfactant [1][2][3][4][5][6][7].…”