The development of new nanomaterials for agricultural and environmental applications is a topical field. To control loading of the bioactive agents and their subsequent release, it is paramount to develop synthetic strategies of well-defined polymeric nanocarriers. Standard characterisation techniques such as DLS and electron microscopy provide useful information on the average size, polydispersity and shape of the nanoparticles but are unable to characterise the inner structure. By using SANS and contrast variation, the proposed experiment aims to develop strategies that could help optimising the properties of the nanocapsules, further control release of the herbicides, and in this way, increase the effectiveness of the nanopesticides in relation to conventional systems.