The invention relates to a device for in vivo sampling of biological species, comprising:—a capture medium made from a nanoporous material, having a capture surface for said species, said capture medium being supported by a plate,—a gripping rod,—an articulation comprising a first limb coupled to the gripping rod and a second limb coupled removably to the plate supporting the capture medium, such that the capture surface can be selectively oriented relative to the gripping rod, so as to adjust the orientation of the capture medium relative to the gripping rod.