Fig. (1) Principles of MALDI-TOF MS technique. The samples are first inserted and embedded in a matrix. A laser pulse is applied in the matrix and the molecules are then both desorbed and ionized by charge transfer. The molecules are accelerated in an electrical field passing through a flight tube and collide with a detector. Biomolecules are separated according to their mass. Finally, a mass spectrum is created which is compared with a database for the identification of the virus.