All-aqueous emulsions are conventionally formed at bulk scale by mild shaking of aqueous two-phase systems. They can be used to carry out reactions both in droplets (compartmentalized) and on droplet surfaces in conditions free of synthetic surfactants and organic solvents. The use of all-aqueous emulsions for extractive bioconversion is a routine application; however, these emulsions hold many more promises. A renowned, rapidly evolving application is bio-microgel synthesis through biopolymer crosslinking within the emulsion internal phase. When polyelectrolyte crosslinking is achieved at the interface rather than in droplets, microcapsules can be formed, and when in situ colloidal particle generation at the droplet surface is obtained, colloidosomes are produced. The use of microfluidics to control the formation of all-aqueous emulsions offers many advantages in reactions monitoring and partitioning of reactants.

通常通过温和摇动水两相体系以本体规模形成全水乳液。它们可用于在无合成表面活性剂和有机溶剂的条件下在液滴（隔室）中和液滴表面上进行反应。全水乳液用于提取生物转化的常规应用。然而，这些乳液具有更多的前景。著名的，迅速发展的应用是通过乳液内相中生物聚合物交联的生物微凝胶合成。当在界面处而不是在液滴中实现聚电解质交联时，可以形成微胶囊，并且在原位形成获得在液滴表面的胶体颗粒的产生，产生胶体。使用微流体来控制全水乳液的形成在反应监测和反应物分配方面具有许多优点。