Embodiments of the invention relate to a device for analyzing a sample surface Comprising an outlet and a frame. The outlet is for forming a jet of gas, the jet forming a sampling region for receiving one or more sample surfaces, and the frame holding the outlet and being adapted to receive a detector means. The detector means has an inlet. In use, the jet produces desorbed sample from sample surfaces received in the sample area. At least a portion of the desorbed sample is ionized to produce one or more sample ions. The frame holds the outlet with respect to the sample ions and produce a signal indicative of the composition of the sample ions.