Graphene is a promising candidate in sensing applications; indeed thanks to its two-dimensionality, it provides the highest surface volume ratio, allowing all its atoms to be totally exposed to the adsorbing gas molecules. Due to several technological limits in production and manipulation of graphene as well as the device fabrication, the synthesis of graphene is still far from a well-settled process. This work aims to illustrate an approach for the graphene preparation that is based on the mechanical exfoliation and circumvents some difficulties encountered in a graphene based nanodevice production. Relying on that fabrication technique a chemiresistive sensor device was prepared. Preliminary findings showed that the device responds to a toxic gas such as up to a few ppm, and reducing gases, such as to few hundred ppm, at room temperature in controlled environments.