Fluorescence-Based Chemical Sensor for Saxitoxin

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Saxitoxin is the primary constituent of the so-called paralytic shellfish poisons (pSPs ). Currently, contamination of shellfish beds by PSPs is monitored by mouse bioassay. </p>
Recently, we have discovered a molecular receptor that "signals" the presence of saxitoxin insolution by emitting light (technically known as enhanced fluorescence emission). This type of phenomenon is of considerable interest to the chemical community in general, but regarding saxitoxin, it could be the key to developing a photochemical sensor that would complement mouse bioassay.</p>
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The first stage of this development, funded by this project, is to study the details of the "recognition" and emission phenomenon between saxitoxin and its receptor, both in solution and at a surface (the air-water interface). </p>
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We will begin by examining the fluorescence emissions quantitatively, then modifying the receptor to optimize its binding and signaling properties. We will modify the receptor to make it amenable to incorporation into a monolayer that, when spread over the surface of water, can be studied in a similar fashion. </p>
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Studying the phenomenon in a monolayer is a prerequisite to development of a sensor using fiber optics.</P>