A Compact Fluorescence Lifetime Excitation-Emission Spectrometer (FLEXEMS) for Detecting Trace Organics

In this Small Business Innovative Research (SBIR) effort, Leiden Measurement Technology (LMT) proposes to design and build the Fluorescence Lifetime Excitation Emission Spectrometer (FLEXEMS), a stand-off fluorescence spectrometer that uses multiple light-emitting diodes to excite fluorescence in samples from the deep-ultraviolet through the visible and employs time-correlated single-photon counting (TCSPC) and steady-state photon-counting techniques to quantify the fluorescence properties of the target in order to detect and identify trace levels of organics in-situ. The addition of fluorescence lifetime measurements distinguishes it from other compact, field-portable instruments available. The instrument will require no reagents or consumables and by simply placing the instrument on a sample of rock, soil, or ice, or other material it will be able to detect a wide range of organics (at or below the 10-100 ppb-level) including free aromatic amino acids; biomarkers including F420 (specific to methanogens), NADH, and proteins; PAHs; and porphyrins (e.g. chlorophyll). It will be designed with flight in mind so that mass, volume, and power-usage will be minimized as much as possible. The use of multi-anode photomultiplier tubes (PMTs) and/or avalanche photodiodes (APDs) will make the system compact and rugged and thus suitable for future missions and ongoing field and laboratory studies.