A portable sampling device (1) for collecting particles in a stream of exhaled breath comprising a housing (10) with an inlet (11) and an outlet (12) arranged to guide the stream of exhaled breath therethrough, a collecting device holder (20) arranged at least partially inside the housing and comprising at least one flow path (21) in fluid connection with the inlet in which a collecting device (30) is arranged, the collecting device being adapted to collect the particles in the exhaled breath, wherein the collecting device has a diameter smaller than the flow path diameter and is movably arranged in the collecting device holder.