Development of a Low-Cost Optical Based Probe for Detection of Red-Tide

Algal toxins can cause mass mortality of wild and farmed fish, contaminate shellfish beds and cause human illnesses from consumption of these products. Dinoflagellates are widely recognized to be the primary algae associated with toxic red tide blooms. Once established, harmful algal blooms typically are mono-specific. The bio-optical "fingerprint" of the bloom, related to the specific pigment composition and rations, is distinct to that species. This lends itself to pigment-based analysis techniques for bloom onset identification, tracking and resource protection. Apprise Technologies, Inc. proposes a novel molecular probe for monitoring photosynthetic pigments in aquatic systems in-situ utilizing a simultaneous narrow-band Reflectance/Absorption/Fluorometric sensor (RAF sensor) for determination of pigment composition and species identification (specifically red tide algae). The concentration of specific pigments will be determined spectrophotometrically and fluormetricly by rapidly scanning water samples with the proposed acoustro- optical tunable filter (AOTF) based Scanning Ratioing Narrow Band Spectrofluorometer (SRNB-SpecF) coupled with an in-situ reflectance probe. This resulting spectral signatures will allow for high sensitivity to pigment composition and species identification. The use of AOTF technology also lends itself to miniaturization resulting in a rugged system for the in-situ determination of pigments without the spectral limitations of current methodology.