The summer is already here, time to enjoy the holidays, the sun, terraces and good weather. However, this idyllic moment can be disturbed by intruders who are never invited, mosquitoes. Mosquitoes, which are nothing more than annoying in our latitudes, are vectors of transmission of many diseases such as malaria, dengue and yellow fever in tropical climates. Mosquitoes are able to smell our presence by CO2 we generate breathing. Thereby, mosquitoes are able to locate where there are potential sources of food. Researches on the tracking system of mosquitoes are the key to creating new biological repellents. MosquiBlock®, owned by Nanobiomatters BactiBlock SL, is a product that incorporates an additive based on citronella, a highly effective natural product as a repellent for insects, such as mosquitoes, horseflies, ticks and flies. MosquiBlock® masks CO emitted by respiration preventing mosquitoes locate potential food sources, providing an atmosphere free of mosquitoes for 24 hours. Its design water soluble and biodegradable doses permits correct product dosification.