A method of detecting organic vapors is described. More particularly, the method involves the use of an analyte sensor that contains a polymeric material having a relatively large intrinsic porosity and that is capable of fluorescence in the visible region of the electromagnetic spectrum. The method further includes exposing the analyte sensor to an environment that may contain an organic vapor and monitoring the analyte sensor for a change in a fluorescence signal. Although the organic vapor itself typically does not fluoresce in the visible wavelength range, presence of an organic vapor can alter the fluorescence signal of the analyte sensor.