Patent ID: 8368883

Claim:
A device for detecting the presence or determining a quantitative amount of an analyte including at least one drug substance, from exhaled breath of a subject in-situ, comprising: a light source, a light detector, at least one optical filter, and at least one waveguide, and a collecting surface comprising of at least one analyte permeable material, and is having at least one Surface Enhanced Raman Spectroscopy (SERS)-active layer that comprises at least one SERS-active material, wherein said collecting surface is arranged as an outer surface of said waveguide for contacting said exhaled breath, such that at least traces of said analyte in said exhaled breath can contact said SERS-active layer, and wherein said at least one waveguide is coupled to said light source and said detector is coupled to said at least one waveguide for a SERS measurement of emitted light from said SERS-active layer, such that a fraction of the light from said light source, when sent through said waveguide, is transmitted from said waveguide at least partly through said outer surface of said at least one waveguide to said at least one SERS-active layer, and a fraction of a SERS-signal emitted from said SERS-active layer is transmitted back into said waveguide, through said filter and further to said detector, whereby a Raman shift spectrum is detectable for said in-situ detecting the presence or determining the quantitative amount of said analyte, such as at least one drug substance from said exhaled breath.