 This paper presents a new type of microspheres made from ionic surfactants that have been cross-linked with catechols. The resulting membrane is extremely thin, 10nm, but still flexible and self-healing. It can be used to create capsules that are impermeable to large molecules such as proteins and cells, which makes them ideal for biomedical applications. This article was authored by Gaya D'Angelis, Natasha Gray, Vivian Lutz Bueno, and others.