Aqueous two-phase system (ATPS), also called “water-in-water” emulsion, is a multi-component system (aqueous droplets dispersed in a continuous aqueous phase), formed after gently mixing two aqueous solutions of immiscible polymers. It allows the formation of different compartments without adding any organic solvent, according to a green process. Nevertheless, the kinetic stability of ATPS is generally difficult to control. Phase diagrams, which express the concentration of a polymer as a function of that of the other in solution, are used to characterise ATPS and to determine conditions for preparing emulsions from selected polymers. In this study, dextran and polyethylene oxide aqueous mixtures with different processing parameters are investigated. Phase diagrams are generated through two automatic methods (Turbiscan and LUMiSizer® technologies) and a manual one. With the diagrams obtained, it is concluded that the purity of polyethylene oxide affects the ATPS, whereas the use of polymers in powder or in solution form has no effect. In view of this result, it is allowed to prepare ATPS formulation by a simple one-step process from polymers in powder form. Graphical abstract

中文翻译：

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水性两相系统：用于表征的简单一步工艺配方和相图

水性两相体系 (ATPS)，也称为“水包水”乳液，是一种多组分体系（水滴分散在连续的水相中），是将两种不混溶聚合物的水溶液轻轻混合后形成的。根据绿色工艺，它允许在不添加任何有机溶剂的情况下形成不同的隔室。然而，ATPS 的动力学稳定性通常难以控制。相图将聚合物的浓度表示为溶液中另一种浓度的函数，用于表征 ATPS 并确定从选定的聚合物制备乳液的条件。在这项研究中，研究了具有不同加工参数的葡聚糖和聚环氧乙烷水性混合物。相图是通过两种自动方法（Turbiscan 和 LUMiSizer® 技术）和一种手动方法生成的。根据所获得的图表，可以得出结论，聚环氧乙烷的纯度会影响 ATPS，而使用粉末或溶液形式的聚合物则没有影响。鉴于这一结果，允许通过简单的一步法从粉末形式的聚合物制备 ATPS 制剂。图形概要