Ethylene oxide and propylene oxide random copolymer/sodium chloride aqueous two‐phase systems: Wetting and adsorption on dodecyl–agarose and polystyrene

Abstract

Liquid/liquid partition chromatography is a mild yet powerful separation method for a variety of biological materials. This work demonstrates that it should be feasible to immobilize an ethylene oxide-propylene oxide (EO/PO) random copolymer solution and to use a solution of NaCl equilibrated against the polymer solution as the mobile-phase (poly (EO-PO) [P(EO-PO)] and NaCl form two aqueous phases known as aqueous two-phase systems). Three random copolymers with different molecular weights and EO/PO ratios were used. Dodecyl-agarose and polystyrene were tested as possible supports. The wetting energies of the aqueous two-phase systems on these two kinds of surfaces were calculated as well as contact angles for each phase on the same surfaces. Finally, the thickness of P(EO-PO) adsorption layers on polystyrene lattices were measured by dynamic light scattering. Contact angle measurements indicate that indeed some EO/PO copolymers preferentially wet hydrophobic substrates, forming thin films.

Extractive Bioconversion of Gamma-Cyclodextrin and Recycling of Cyclodextrin Glycosyltransferase in Liquid Biphasic System Using Thermo-Separating Polymer

“…The EOPO 970 with lower PO content (50%) results in higher Y T of γ-CD in comparison with EOPO with higher PO content (EOPO 3900, EOPO 12000). The lower PO content of EOPOs (EOPO 970) allows maximum solubility of γ-CD in the polymer phase, thereby making the γ-CD precipitation in the interphase avoidable (Huang and Forciniti, 2002 ). The K CGTase values generally decreased as TLL increased.…”

Adsorption of Diblock Polypeptides on Polystyrene Latex

“…The technique measures diffusivity (D), which can be related to the particle size. 31 For noninteracting uniform spheres, the Stoke−Einstein equation gives:…”

“…The size difference divided by 2 yields the average thickness of the adsorbed layer. The technique measures diffusivity ( D ), which can be related to the particle size . For noninteracting uniform spheres, the Stoke–Einstein equation gives: where k B is Boltzmann’s constant, T is the temperature in K, η is the viscosity of the fluid in which the particles are moving, and D h is the hydrodynamic diameter of the particles.…”

Emerging Biotechnology Applications of Aqueous Two‐Phase Systems

“…[53,54] Finally, in addition to the effects of ATPS hydrophobicity on partitioning, it is also important to consider the interaction of the fluid phases with solid substrates based on surface chemistry. [55] The surface chemistry of the container holding the ATPS will influence the wettability by one or both of the phase-forming polymers. In the case of the solution micropatterning applications discussed later, this has the effect of lowering the droplet contact angle, i.e., droplets will have the tendency to spread more.…”

“…ATPSs have also been used to evaluate surface net hydrophobicity of proteins . Finally, in addition to the effects of ATPS hydrophobicity on partitioning, it is also important to consider the interaction of the fluid phases with solid substrates based on surface chemistry . The surface chemistry of the container holding the ATPS will influence the wettability by one or both of the phase‐forming polymers.…”