Patent ID: 8759791

Claim:
An in situ method for repeatedly sensing of volatile organic compounds (VOCs), comprising: a. providing a sample chamber in which a specific VOC, or combination of VOCs of interest, can enter while in a vapor state from the surrounding atmospheric environment and then be located at a sample location; b. varying the temperature of the sample location to provide repeated collection of VOCs from the surrounding atmospheric environment at the sample location and repeated removal of VOCs from the sample location to refresh the sample location in preparation for subsequent VOC collection; c. providing excitation radiation onto the sample location wherein the excitation radiation has a wavelength in the ultraviolet range and wherein the sample location has a temperature that is different from ambient temperature; d. receiving native fluorescence emission radiation, from the sample location arising from the excitation radiation, onto at least one optical element which directs the fluorescence radiation along at least one detection path; e. detecting the native fluorescence emission at at least one location along the detection path; f. determining whether the detected native fluorescence corresponds to a VOC of interest; and g. refreshing the sample location and repeating the receiving, detecting, and determining a plurality of times to provide updated information on the presence of the VOC or VOCs of interest in the surrounding atmospheric environment.