Abstract: Procedure for detection of chemical species and device which carries out said procedure, whereby chemical species are to be considered those species formed either by molecules or by more complex compounds with sizes which can reach submicrometer scales. This procedure is characterized in the use of a sequential set of stages which allows different classification criteria to be applied to allow the presence or absence of target species to be discerned with an almost negligible failure rate. The device which implements these stages applies each discrimination criterion making use of modules capable of distinguishing two species according to a different physical, electrical, or chemical property.