Native fluorescence detection methods, devices, and systems for organic compounds

Inventors

Hug, William F. • Bhartia, Rohit • Reid, Ray D. • Lane, Arthur L.

Assignees

Photon Systems Inc

Abstract

Naphthalene, benzene, toluene, xylene, and other volatile organic compounds VOCs have been identified as serious health hazards. Embodiments of the invention are directed to methods and apparatus for near-real-time in-situ detection and accumulated dose measurement of exposure to naphthalene vapor and other hazardous gaseous VOCs. The methods and apparatus employ excitation of fluorophors native or endogenous to compounds of interest using light sources emitting in the ultraviolet below 300 nm and measurement of native fluorescence emissions in distinct wavebands above the excitation wavelength. The apparatus of some embodiments are cell-phone-sized sensor/dosimeter “badges” to be worn by personnel potentially exposed to hazardous VOCs. The badge sensor of some embodiments provides both real time detection and data logging of exposure to naphthalene or other VOCs of interest from which both instantaneous and accumulated dose can be determined.

Core Innovation

The invention relates to an apparatus for sensing and detecting at least one volatile organic compound (VOC) using excitation radiation having a wavelength less than 300 nm. The apparatus directs excitation radiation onto a sample location within a housing and receives emission radiation from the sample location along at least one detection path within the housing, and the determination is made based at least in part on the detected emission radiation.

In representative embodiments, the emission radiation includes native fluorescence emission radiation produced by endogenous fluorophors when the sample is exposed to the excitation radiation. At least one optical element directs the emission radiation along detection paths within the housing to at least one detector located along the detection paths, and electronic analysis compares detected native fluorescence emission radiation to stored data to determine the presence of a VOC of interest, a concentration of an amount of a VOC present, or both qualitative presence and concentration.

The apparatus further includes a temperature control element for modifying the temperature of the sample location from below ambient temperature to at least ambient temperature, and a controller that controls operation of the source, the temperature control element, and the detector. The described system supports compact wearable badge form factors and enables near-real-time and dosimetry-style detection via instantaneous and accumulated exposure determinations based on the detected emission radiation.

Claims Coverage

The partial content includes three independent claims for VOC sensing and detection apparatuses, and each centers on UV excitation below 300 nm, optical collection of emission radiation through detection paths, detection by one or more detectors, and analyzer circuitry to determine presence and/or concentration. Across the independent claims, at least five main inventive features are explicitly recited.

Across the independent claims, the apparatuses detect VOCs by directing UV excitation radiation with a wavelength less than 300 nm onto a sample location within a housing, collecting resulting emission radiation including native fluorescence using optical elements that route emission along detection paths, detecting the emission with one or more detectors, and using controller or analyzer circuitry to determine presence and/or concentration. The claim set also explicitly includes sample-location temperature modification from below ambient temperature to at least ambient temperature, and at least one configuration that uses multiple detectors on multiple paths without a dispersive optical element with electronic comparison to stored data.

Stated Advantages

Documented Applications