Project Title:

Polestar Technologies, Inc.
7 Wells Avenue
Newton Centre, MA 02159

93-01 12.08   1083  AMOUNT REQUESTED $ 69,898

In Situ Metal Ion Sensors for Monitoring and Control of Nutrient Solutions

This Phase I proposal addresses the need to develop in situ, multi-
element sensor arrays for nutrient solution analysis. Various
macrocycle compounds have been shown to uniquely complex metal
ions. The innovation is to use chromogenic macrocycle compounds,
which are currently under development, and optical transduction
principles, to fabricate and test metal ion sensors. The Phase I
work includes fabrication of these recognition elements; attachment
to optical substrates; and spectrophotometric characterization in
the presence of select metal ions to determine sensitivity,
response time, reversibility, linearity and stability. Preliminary
evaluation in multicomponent and mixed metal solutions will be
performed in Phase I.
Simple, reliable, in situ sensors to monitor dissolved metal ions
do not exist at present. In a Phase II effort, a prototype Metal
Ion Sensor Array will be fabricated, tested, and delivered to NASA
for evaluation in a Nutrient Delivery System. This sensor system
could also be used to assure the quality in water reclamation
systems currently under development by NASA for use in long-
duration space flight, and could be used as part of a mobile
robotics laboratory for exobiology experimentation and sampling.

Dissolved metal ions pose direct health risks to humans, and
secondary risks from effects on food supplies (e.g., fish, plants).
Metal ion sensor arrays could be used for real time, cost-effective
monitoring of the quality of potable and natural waters,
water/waste processing systems, industrial process control, and, in
food processing, for on-line nutrient analysis.

metal ions, optical sensors, water quality, nutrient analysis