Vesicle compositions are provided that comprise a therapeutic compound. The vesicle compositions may be capable of releasing the therapeutic compound in response to the presence of an external trigger. The vesicle compositions may comprise a plurality of biocompatible vesicles. The biocompatible vesicles may comprise a therapeutic compound for treatment of a patient in need thereof, and one or more cross-linkages between two or more of the biocompatible vesicles, each cross-linkage comprising a chemical sensing moiety and a sensed moiety. In some embodiments, the therapeutic compound may be any compound that provides palliative, curative, or otherwise beneficial effects to a patent.